Btrfs device related enhancements #3
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Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
This will return EIO when __bread() fails to read SB, instead of EINVAL. Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
…INTK defined
error handling logic behaves differently with or without
CONFIG_PRINTK defined, since there are two copies of the same
function which a bit of different logic
One, when CONFIG_PRINTK is defined, code is
__btrfs_std_error(..)
{
::
save_error_info(fs_info);
if (sb->s_flags & MS_BORN)
btrfs_handle_error(fs_info);
}
and two when CONFIG_PRINTK is not defined, the code is
__btrfs_std_error(..)
{
::
if (sb->s_flags & MS_BORN) {
save_error_info(fs_info);
btrfs_handle_error(fs_info);
}
}
I doubt if this was intentional ? and appear to have caused since
we maintain two copies of the same function and they got diverged
with commits.
Now to decide which logic is correct reviewed changes as below,
533574c
Commit added two copies of this function
cf79ffb
Commit made change to only one copy of the function and to the
copy when CONFIG_PRINTK is defined.
To fix this, instead of maintaining two copies of same function
approach, maintain single function, and just put the extra
portion of the code under CONFIG_PRINTK define.
This patch just does that. And keeps code of with CONFIG_PRINTK
defined.
Signed-off-by: Anand Jain <[email protected]>
Signed-off-by: David Sterba <[email protected]>
btrfs_error() and btrfs_std_error() does the same thing and calls _btrfs_std_error(), so consolidate them together. And the main motivation is that btrfs_error() is closely named with btrfs_err(), one handles error action the other is to log the error, so don't closely name them. Signed-off-by: Anand Jain <[email protected]> Suggested-by: David Sterba <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]>
…ot found Use btrfs specific error code BTRFS_ERROR_DEV_MISSING_NOT_FOUND instead of -ENOENT. Next this removes the logging when user specifies "missing" and we don't find it in the kernel device list. Logging are for system events not for user input errors. Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
This uses a chunk of code from btrfs_read_dev_super() and creates a function called btrfs_read_dev_one_super() so that next patch can use it for scratch superblock. Signed-off-by: Anand Jain <[email protected]> [renamed bufhead to bh] Signed-off-by: David Sterba <[email protected]>
This patch updates and renames btrfs_scratch_superblocks, (which is used by the replace device thread), with those fixes from the scratch superblock code section of btrfs_rm_device(). The fixes are: Scratch all copies of superblock Notify kobject that superblock has been changed Update time on the device So that btrfs_rm_device() can use the function btrfs_scratch_superblocks() instead of its own scratch code. And further replace deivce code which similarly releases device back to the system, will have the fixes from the btrfs device delete. Signed-off-by: Anand Jain <[email protected]> [renamed to btrfs_scratch_superblock] Signed-off-by: David Sterba <[email protected]>
By general rule of thumb there shouldn't be any way that user land could trigger a kernel operation just by sending wrong arguments. Here do commit cleanups after user input has been verified. Signed-off-by: Anand Jain <[email protected]> Signed-off-by: David Sterba <[email protected]>
Originally the message was not in a helper but ended up there. We should print error messages from callers instead. Signed-off-by: Anand Jain <[email protected]> [reworded subject and changelog] Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Anand Jain <[email protected]> [reworded subject and changelog] Signed-off-by: David Sterba <[email protected]>
To avoid deadlock described in commit 084b6e7 ("btrfs: Fix a lockdep warning when running xfstest."), we should move kobj stuff out of dev_replace lock range. "It is because the btrfs_kobj_{add/rm}_device() will call memory allocation with GFP_KERNEL, which may flush fs page cache to free space, waiting for it self to do the commit, causing the deadlock. To solve the problem, move btrfs_kobj_{add/rm}_device() out of the dev_replace lock range, also involing split the btrfs_rm_dev_replace_srcdev() function into remove and free parts. Now only btrfs_rm_dev_replace_remove_srcdev() is called in dev_replace lock range, and kobj_{add/rm} and btrfs_rm_dev_replace_free_srcdev() are called out of the lock range." Signed-off-by: Liu Bo <[email protected]> Signed-off-by: Anand Jain <[email protected]> [added lockup description] Signed-off-by: David Sterba <[email protected]>
This patch will log return value of add/del_qgroup_relation() and pass the err code of btrfs_run_qgroups to the btrfs_std_error(). Signed-off-by: Anand Jain <[email protected]>
A part of code from btrfs_scan_one_device() is moved to a new function btrfs_read_disk_super(), so that former function looks cleaner and moves the code to ensure null terminating label to it as well. Further there is opportunity to merge various duplicate code on read disk super. Earlier attempt on this was highlighted that there was some issues for which there are multiple versions, however it was not clear what was issue. So until its worked out we can keep it in a separate function. Signed-off-by: Anand Jain <[email protected]>
Optional Label may or may not be set, or it might be set at some time later. However while debugging to search through the kernel logs the scripts would need the logs to be consistent, so logs search key words shouldn't depend on the optional variables, instead fsid is better. Signed-off-by: Anand Jain <[email protected]>
From the issue diagnosable point of view, log if the device path is changed. Signed-off-by: Anand Jain <[email protected]>
Looks like oversight, call brelse() when checksum fails. Further down the code, in the non error path, we do call brelse() and so we don't see brelse() in the goto error paths. Signed-off-by: Anand Jain <[email protected]>
This adds an enhancement to show the seed fsid and its devices
on the btrfs sysfs.
The way sprouting handles fs_devices:
clone seed fs_devices and add to the fs_uuids
mem copy seed fs_devices and assign to fs_devices->seed (move dev_list)
evacuate seed fs_devices contents to hold sprout fs devices contents
So to be inline with this fs_devices changes during seeding,
represent seed fsid under the sprout fsid, this is achieved
by using the kobject_move()
The end result will be,
/sys/fs/btrfs/sprout-fsid/seed/level-1-seed-fsid/seed/(if)level-2-seed-fsid
Signed-off-by: Anand Jain <[email protected]>
We need fsid kobject to hold pool attributes however its created only when fs is mounted. So, this patch changes the life cycle of the fsid and devices kobjects /sys/fs/btrfs/<fsid> and /sys/fs/btrfs/<fsid>/devices, from created and destroyed by mount and unmount event to created and destroyed by scanned and module-unload events respectively. However this does not alter life cycle of fs attributes as such. Signed-off-by: Anand Jain <[email protected]>
move a section of btrfs_rm_device() code to check for min number
of the devices into the function __check_raid_min_devices()
v2: commit update and title renamed from
Btrfs: move check for min number of devices to a function
Signed-off-by: Anand Jain <[email protected]>
__check_raid_min_device() which was pealed from btrfs_rm_device() maintianed its original code to show the block move. This patch cleans up __check_raid_min_device(). Signed-off-by: Anand Jain <[email protected]>
The patch renames btrfs_dev_replace_find_srcdev() to
btrfs_find_device_by_user_input() and moves it to volumes.c.
so that delete device can use it.
v2: changed title from
'Btrfs: create rename btrfs_dev_replace_find_srcdev()'
and commit update
Signed-off-by: Anand Jain <[email protected]>
btrfs_rm_device() has a section of the code which can be replaced btrfs_find_device_by_user_input() Signed-off-by: Anand Jain <[email protected]>
The operation of device replace and device delete follows same steps upto some depth with in btrfs kernel, however they don't share codes. This enhancement will help replace and delete to share codes. Btrfs: enhance check device_path in btrfs_find_device_by_user_input() Signed-off-by: Anand Jain <[email protected]>
With the previous patches now the btrfs_scratch_superblocks() is ready to be used in btrfs_rm_device() so use it. Signed-off-by: Anand Jain <[email protected]>
This patch makes btrfs_fs_devices and btrfs_device information readable
from sysfs. This uses the sysfs group visible entry point to mark certain
attributes visible/hidden depending the FS state.
The new extended layout is as shown below.
/sys/fs/btrfs/
./7b047f4d-c2ce-4f22-94a3-68c09057f1bf*
fsid*
missing_devices
num_devices*
open_devices
opened*
rotating
rw_devices
seeding
total_devices*
total_rw_bytes
./e6701882-220a-4416-98ac-a99f095bddcc*
active_pending
bdev
bytes_used
can_discard
devid*
dev_root_fsid
devstats_valid
dev_totalbytes
generation*
in_fs_metadata
io_align
io_width
missing
name*
nobarriers
replace_tgtdev
sector_size
total_bytes
type
uuid*
writeable
(* indicates that attribute will be visible even when device is
unmounted but registered with btrfs kernel)
v2: use btrfs_error() not btrfs_err()
reword subject form :
Btrfs: add sysfs layout to show btrfs_fs_devices and btrfs_device attributes
Signed-off-by: Anand Jain <[email protected]>
kdave
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that referenced
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Jul 15, 2025
When operating in concurrent STA/AP mode with host MLME enabled, the firmware incorrectly sends disassociation frames to the STA interface when clients disconnect from the AP interface. This causes kernel warnings as the STA interface processes disconnect events that don't apply to it: [ 1303.240540] WARNING: CPU: 0 PID: 513 at net/wireless/mlme.c:141 cfg80211_process_disassoc+0x78/0xec [cfg80211] [ 1303.250861] Modules linked in: 8021q garp stp mrp llc rfcomm bnep btnxpuart nls_iso8859_1 nls_cp437 onboard_us [ 1303.327651] CPU: 0 UID: 0 PID: 513 Comm: kworker/u9:2 Not tainted 6.16.0-rc1+ #3 PREEMPT [ 1303.335937] Hardware name: Toradex Verdin AM62 WB on Verdin Development Board (DT) [ 1303.343588] Workqueue: MWIFIEX_RX_WORK_QUEUE mwifiex_rx_work_queue [mwifiex] [ 1303.350856] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1303.357904] pc : cfg80211_process_disassoc+0x78/0xec [cfg80211] [ 1303.364065] lr : cfg80211_process_disassoc+0x70/0xec [cfg80211] [ 1303.370221] sp : ffff800083053be0 [ 1303.373590] x29: ffff800083053be0 x28: 0000000000000000 x27: 0000000000000000 [ 1303.380855] x26: 0000000000000000 x25: 00000000ffffffff x24: ffff000002c5b8ae [ 1303.388120] x23: ffff000002c5b884 x22: 0000000000000001 x21: 0000000000000008 [ 1303.395382] x20: ffff000002c5b8ae x19: ffff0000064dd408 x18: 0000000000000006 [ 1303.402646] x17: 3a36333a61623a30 x16: 32206d6f72662063 x15: ffff800080bfe048 [ 1303.409910] x14: ffff000003625300 x13: 0000000000000001 x12: 0000000000000000 [ 1303.417173] x11: 0000000000000002 x10: ffff000003958600 x9 : ffff000003625300 [ 1303.424434] x8 : ffff00003fd9ef40 x7 : ffff0000039fc280 x6 : 0000000000000002 [ 1303.431695] x5 : ffff0000038976d4 x4 : 0000000000000000 x3 : 0000000000003186 [ 1303.438956] x2 : 000000004836ba20 x1 : 0000000000006986 x0 : 00000000d00479de [ 1303.446221] Call trace: [ 1303.448722] cfg80211_process_disassoc+0x78/0xec [cfg80211] (P) [ 1303.454894] cfg80211_rx_mlme_mgmt+0x64/0xf8 [cfg80211] [ 1303.460362] mwifiex_process_mgmt_packet+0x1ec/0x460 [mwifiex] [ 1303.466380] mwifiex_process_sta_rx_packet+0x1bc/0x2a0 [mwifiex] [ 1303.472573] mwifiex_handle_rx_packet+0xb4/0x13c [mwifiex] [ 1303.478243] mwifiex_rx_work_queue+0x158/0x198 [mwifiex] [ 1303.483734] process_one_work+0x14c/0x28c [ 1303.487845] worker_thread+0x2cc/0x3d4 [ 1303.491680] kthread+0x12c/0x208 [ 1303.495014] ret_from_fork+0x10/0x20 Add validation in the STA receive path to verify that disassoc/deauth frames originate from the connected AP. Frames that fail this check are discarded early, preventing them from reaching the MLME layer and triggering WARN_ON(). This filtering logic is similar with that used in the ieee80211_rx_mgmt_disassoc() function in mac80211, which drops disassoc frames that don't match the current BSSID (!ether_addr_equal(mgmt->bssid, sdata->vif.cfg.ap_addr)), ensuring only relevant frames are processed. Tested on: - 8997 with FW 16.68.1.p197 Fixes: 3699589 ("wifi: mwifiex: add host mlme for client mode") Cc: [email protected] Signed-off-by: Vitor Soares <[email protected]> Reviewed-by: Jeff Chen <[email protected]> Reviewed-by: Francesco Dolcini <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Johannes Berg <[email protected]>
kdave
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that referenced
this pull request
Jul 15, 2025
alloc_tag_top_users() attempts to lock alloc_tag_cttype->mod_lock even
when the alloc_tag_cttype is not allocated because:
1) alloc tagging is disabled because mem profiling is disabled
(!alloc_tag_cttype)
2) alloc tagging is enabled, but not yet initialized (!alloc_tag_cttype)
3) alloc tagging is enabled, but failed initialization
(!alloc_tag_cttype or IS_ERR(alloc_tag_cttype))
In all cases, alloc_tag_cttype is not allocated, and therefore
alloc_tag_top_users() should not attempt to acquire the semaphore.
This leads to a crash on memory allocation failure by attempting to
acquire a non-existent semaphore:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#3] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]
CPU: 2 UID: 0 PID: 1 Comm: systemd Tainted: G D 6.16.0-rc2 #1 VOLUNTARY
Tainted: [D]=DIE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:down_read_trylock+0xaa/0x3b0
Code: d0 7c 08 84 d2 0f 85 a0 02 00 00 8b 0d df 31 dd 04 85 c9 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 6b 68 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 88 02 00 00 48 3b 5b 68 0f 85 53 01 00 00 65 ff
RSP: 0000:ffff8881002ce9b8 EFLAGS: 00010016
RAX: dffffc0000000000 RBX: 0000000000000070 RCX: 0000000000000000
RDX: 000000000000001b RSI: 000000000000000a RDI: 0000000000000070
RBP: 00000000000000d8 R08: 0000000000000001 R09: ffffed107dde49d1
R10: ffff8883eef24e8b R11: ffff8881002cec20 R12: 1ffff11020059d37
R13: 00000000003fff7b R14: ffff8881002cec20 R15: dffffc0000000000
FS: 00007f963f21d940(0000) GS:ffff888458ca6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f963f5edf71 CR3: 000000010672c000 CR4: 0000000000350ef0
Call Trace:
<TASK>
codetag_trylock_module_list+0xd/0x20
alloc_tag_top_users+0x369/0x4b0
__show_mem+0x1cd/0x6e0
warn_alloc+0x2b1/0x390
__alloc_frozen_pages_noprof+0x12b9/0x21a0
alloc_pages_mpol+0x135/0x3e0
alloc_slab_page+0x82/0xe0
new_slab+0x212/0x240
___slab_alloc+0x82a/0xe00
</TASK>
As David Wang points out, this issue became easier to trigger after commit
780138b ("alloc_tag: check mem_profiling_support in alloc_tag_init").
Before the commit, the issue occurred only when it failed to allocate and
initialize alloc_tag_cttype or if a memory allocation fails before
alloc_tag_init() is called. After the commit, it can be easily triggered
when memory profiling is compiled but disabled at boot.
To properly determine whether alloc_tag_init() has been called and its
data structures initialized, verify that alloc_tag_cttype is a valid
pointer before acquiring the semaphore. If the variable is NULL or an
error value, it has not been properly initialized. In such a case, just
skip and do not attempt to acquire the semaphore.
[[email protected]: v3]
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: 780138b ("alloc_tag: check mem_profiling_support in alloc_tag_init")
Fixes: 1438d34 ("lib: add memory allocations report in show_mem()")
Signed-off-by: Harry Yoo <[email protected]>
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-lkp/[email protected]
Acked-by: Suren Baghdasaryan <[email protected]>
Tested-by: Raghavendra K T <[email protected]>
Cc: Casey Chen <[email protected]>
Cc: David Wang <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Yuanyuan Zhong <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
kdave
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Jul 16, 2025
If "try_verify_in_tasklet" is set for dm-verity, DM_BUFIO_CLIENT_NO_SLEEP
is enabled for dm-bufio. However, when bufio tries to evict buffers, there
is a chance to trigger scheduling in spin_lock_bh, the following warning
is hit:
BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2745
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 123, name: kworker/2:2
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
4 locks held by kworker/2:2/123:
#0: ffff88800a2d1548 ((wq_completion)dm_bufio_cache){....}-{0:0}, at: process_one_work+0xe46/0x1970
#1: ffffc90000d97d20 ((work_completion)(&dm_bufio_replacement_work)){....}-{0:0}, at: process_one_work+0x763/0x1970
#2: ffffffff8555b528 (dm_bufio_clients_lock){....}-{3:3}, at: do_global_cleanup+0x1ce/0x710
#3: ffff88801d5820b8 (&c->spinlock){....}-{2:2}, at: do_global_cleanup+0x2a5/0x710
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 2 UID: 0 PID: 123 Comm: kworker/2:2 Not tainted 6.16.0-rc3-g90548c634bd0 torvalds#305 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: dm_bufio_cache do_global_cleanup
Call Trace:
<TASK>
dump_stack_lvl+0x53/0x70
__might_resched+0x360/0x4e0
do_global_cleanup+0x2f5/0x710
process_one_work+0x7db/0x1970
worker_thread+0x518/0xea0
kthread+0x359/0x690
ret_from_fork+0xf3/0x1b0
ret_from_fork_asm+0x1a/0x30
</TASK>
That can be reproduced by:
veritysetup format --data-block-size=4096 --hash-block-size=4096 /dev/vda /dev/vdb
SIZE=$(blockdev --getsz /dev/vda)
dmsetup create myverity -r --table "0 $SIZE verity 1 /dev/vda /dev/vdb 4096 4096 <data_blocks> 1 sha256 <root_hash> <salt> 1 try_verify_in_tasklet"
mount /dev/dm-0 /mnt -o ro
echo 102400 > /sys/module/dm_bufio/parameters/max_cache_size_bytes
[read files in /mnt]
Cc: [email protected] # v6.4+
Fixes: 450e8de ("dm bufio: improve concurrent IO performance")
Signed-off-by: Wang Shuai <[email protected]>
Signed-off-by: Sheng Yong <[email protected]>
Signed-off-by: Mikulas Patocka <[email protected]>
kdave
pushed a commit
that referenced
this pull request
Jul 21, 2025
If the PHY driver uses another PHY internally (e.g. in case of eUSB2,
repeaters are represented as PHYs), then it would trigger the following
lockdep splat because all PHYs use a single static lockdep key and thus
lockdep can not identify whether there is a dependency or not and
reports a false positive.
Make PHY subsystem use dynamic lockdep keys, assigning each driver a
separate key. This way lockdep can correctly identify dependency graph
between mutexes.
============================================
WARNING: possible recursive locking detected
6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 Not tainted
--------------------------------------------
kworker/u51:0/78 is trying to acquire lock:
ffff0008116554f0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c
but task is already holding lock:
ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&phy->mutex);
lock(&phy->mutex);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by kworker/u51:0/78:
#0: ffff000800010948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x18c/0x5ec
#1: ffff80008036bdb0 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work+0x1b4/0x5ec
#2: ffff0008094ac8f8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x38/0x188
#3: ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c
stack backtrace:
CPU: 0 UID: 0 PID: 78 Comm: kworker/u51:0 Not tainted 6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 PREEMPT
Hardware name: Qualcomm CRD, BIOS 6.0.240904.BOOT.MXF.2.4-00528.1-HAMOA-1 09/ 4/2024
Workqueue: events_unbound deferred_probe_work_func
Call trace:
show_stack+0x18/0x24 (C)
dump_stack_lvl+0x90/0xd0
dump_stack+0x18/0x24
print_deadlock_bug+0x258/0x348
__lock_acquire+0x10fc/0x1f84
lock_acquire+0x1c8/0x338
__mutex_lock+0xb8/0x59c
mutex_lock_nested+0x24/0x30
phy_init+0x4c/0x12c
snps_eusb2_hsphy_init+0x54/0x1a0
phy_init+0xe0/0x12c
dwc3_core_init+0x450/0x10b4
dwc3_core_probe+0xce4/0x15fc
dwc3_probe+0x64/0xb0
platform_probe+0x68/0xc4
really_probe+0xbc/0x298
__driver_probe_device+0x78/0x12c
driver_probe_device+0x3c/0x160
__device_attach_driver+0xb8/0x138
bus_for_each_drv+0x84/0xe0
__device_attach+0x9c/0x188
device_initial_probe+0x14/0x20
bus_probe_device+0xac/0xb0
deferred_probe_work_func+0x8c/0xc8
process_one_work+0x208/0x5ec
worker_thread+0x1c0/0x368
kthread+0x14c/0x20c
ret_from_fork+0x10/0x20
Fixes: 3584f63 ("phy: qcom: phy-qcom-snps-eusb2: Add support for eUSB2 repeater")
Fixes: e246355 ("phy: amlogic: Add Amlogic AXG PCIE PHY Driver")
Reviewed-by: Neil Armstrong <[email protected]>
Reviewed-by: Abel Vesa <[email protected]>
Reported-by: Johan Hovold <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Reviewed-by: Johan Hovold <[email protected]>
Tested-by: Johan Hovold <[email protected]>
Signed-off-by: Dmitry Baryshkov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>
kdave
pushed a commit
that referenced
this pull request
Jul 24, 2025
The AARP proxy‐probe routine (aarp_proxy_probe_network) sends a probe,
releases the aarp_lock, sleeps, then re-acquires the lock. During that
window an expire timer thread (__aarp_expire_timer) can remove and
kfree() the same entry, leading to a use-after-free.
race condition:
cpu 0 | cpu 1
atalk_sendmsg() | atif_proxy_probe_device()
aarp_send_ddp() | aarp_proxy_probe_network()
mod_timer() | lock(aarp_lock) // LOCK!!
timeout around 200ms | alloc(aarp_entry)
and then call | proxies[hash] = aarp_entry
aarp_expire_timeout() | aarp_send_probe()
| unlock(aarp_lock) // UNLOCK!!
lock(aarp_lock) // LOCK!! | msleep(100);
__aarp_expire_timer(&proxies[ct]) |
free(aarp_entry) |
unlock(aarp_lock) // UNLOCK!! |
| lock(aarp_lock) // LOCK!!
| UAF aarp_entry !!
==================================================================
BUG: KASAN: slab-use-after-free in aarp_proxy_probe_network+0x560/0x630 net/appletalk/aarp.c:493
Read of size 4 at addr ffff8880123aa360 by task repro/13278
CPU: 3 UID: 0 PID: 13278 Comm: repro Not tainted 6.15.2 #3 PREEMPT(full)
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1b0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc1/0x630 mm/kasan/report.c:521
kasan_report+0xca/0x100 mm/kasan/report.c:634
aarp_proxy_probe_network+0x560/0x630 net/appletalk/aarp.c:493
atif_proxy_probe_device net/appletalk/ddp.c:332 [inline]
atif_ioctl+0xb58/0x16c0 net/appletalk/ddp.c:857
atalk_ioctl+0x198/0x2f0 net/appletalk/ddp.c:1818
sock_do_ioctl+0xdc/0x260 net/socket.c:1190
sock_ioctl+0x239/0x6a0 net/socket.c:1311
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:906 [inline]
__se_sys_ioctl fs/ioctl.c:892 [inline]
__x64_sys_ioctl+0x194/0x200 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcb/0x250 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
Allocated:
aarp_alloc net/appletalk/aarp.c:382 [inline]
aarp_proxy_probe_network+0xd8/0x630 net/appletalk/aarp.c:468
atif_proxy_probe_device net/appletalk/ddp.c:332 [inline]
atif_ioctl+0xb58/0x16c0 net/appletalk/ddp.c:857
atalk_ioctl+0x198/0x2f0 net/appletalk/ddp.c:1818
Freed:
kfree+0x148/0x4d0 mm/slub.c:4841
__aarp_expire net/appletalk/aarp.c:90 [inline]
__aarp_expire_timer net/appletalk/aarp.c:261 [inline]
aarp_expire_timeout+0x480/0x6e0 net/appletalk/aarp.c:317
The buggy address belongs to the object at ffff8880123aa300
which belongs to the cache kmalloc-192 of size 192
The buggy address is located 96 bytes inside of
freed 192-byte region [ffff8880123aa300, ffff8880123aa3c0)
Memory state around the buggy address:
ffff8880123aa200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8880123aa280: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880123aa300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880123aa380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff8880123aa400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
Fixes: 1da177e ("Linux-2.6.12-rc2")
Signed-off-by: Kito Xu (veritas501) <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
kdave
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Aug 16, 2025
The existing code move the VF NIC to new namespace when NETDEV_REGISTER is received on netvsc NIC. During deletion of the namespace, default_device_exit_batch() >> default_device_exit_net() is called. When netvsc NIC is moved back and registered to the default namespace, it automatically brings VF NIC back to the default namespace. This will cause the default_device_exit_net() >> for_each_netdev_safe loop unable to detect the list end, and hit NULL ptr: [ 231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0 [ 231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 231.450246] #PF: supervisor read access in kernel mode [ 231.450579] #PF: error_code(0x0000) - not-present page [ 231.450916] PGD 17b8a8067 P4D 0 [ 231.451163] Oops: Oops: 0000 [#1] SMP NOPTI [ 231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY [ 231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 231.452692] Workqueue: netns cleanup_net [ 231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0 [ 231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00 [ 231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246 [ 231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb [ 231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564 [ 231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000 [ 231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340 [ 231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340 [ 231.457161] FS: 0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000 [ 231.457707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0 [ 231.458434] Call Trace: [ 231.458600] <TASK> [ 231.458777] ops_undo_list+0x100/0x220 [ 231.459015] cleanup_net+0x1b8/0x300 [ 231.459285] process_one_work+0x184/0x340 To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid changing the netdev list when default_device_exit_net() is using it. Cc: [email protected] Fixes: 4c26280 ("hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event") Signed-off-by: Haiyang Zhang <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
kdave
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Aug 21, 2025
…dlock When a user creates a dualpi2 qdisc it automatically sets a timer. This timer will run constantly and update the qdisc's probability field. The issue is that the timer acquires the qdisc root lock and runs in hardirq. The qdisc root lock is also acquired in dev.c whenever a packet arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq, it may interrupt the packet processing running in softirq. If that happens and it runs on the same CPU, it will acquire the same lock and cause a deadlock. The following splat shows up when running a kernel compiled with lock debugging: [ +0.000224] WARNING: inconsistent lock state [ +0.000224] 6.16.0+ #10 Not tainted [ +0.000169] -------------------------------- [ +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. [ +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes: [ +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140 [ +0.000000] {IN-HARDIRQ-W} state was registered at: [ +0.000000] lock_acquire.part.0+0xb6/0x220 [ +0.000000] _raw_spin_lock+0x31/0x80 [ +0.000000] dualpi2_timer+0x6f/0x270 [ +0.000000] __hrtimer_run_queues+0x1c5/0x360 [ +0.000000] hrtimer_interrupt+0x115/0x260 [ +0.000000] __sysvec_apic_timer_interrupt+0x6d/0x1a0 [ +0.000000] sysvec_apic_timer_interrupt+0x6e/0x80 [ +0.000000] asm_sysvec_apic_timer_interrupt+0x1a/0x20 [ +0.000000] pv_native_safe_halt+0xf/0x20 [ +0.000000] default_idle+0x9/0x10 [ +0.000000] default_idle_call+0x7e/0x1e0 [ +0.000000] do_idle+0x1e8/0x250 [ +0.000000] cpu_startup_entry+0x29/0x30 [ +0.000000] rest_init+0x151/0x160 [ +0.000000] start_kernel+0x6f3/0x700 [ +0.000000] x86_64_start_reservations+0x24/0x30 [ +0.000000] x86_64_start_kernel+0xc8/0xd0 [ +0.000000] common_startup_64+0x13e/0x148 [ +0.000000] irq event stamp: 6884 [ +0.000000] hardirqs last enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270 [ +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270 [ +0.000000] softirqs last enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270 [ +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140 [ +0.000000] other info that might help us debug this: [ +0.000000] Possible unsafe locking scenario: [ +0.000000] CPU0 [ +0.000000] ---- [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] <Interrupt> [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] *** DEADLOCK *** [ +0.000000] 4 locks held by ping/156: [ +0.000000] #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40 [ +0.000000] #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190 [ +0.000000] #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950 [ +0.000000] #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140 I am able to reproduce it consistently when running the following: tc qdisc add dev lo handle 1: root dualpi2 ping -f 127.0.0.1 To fix it, make the timer run in softirq. Fixes: 320d031 ("sched: Struct definition and parsing of dualpi2 qdisc") Reviewed-by: Jamal Hadi Salim <[email protected]> Signed-off-by: Victor Nogueira <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
kdave
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Aug 25, 2025
Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") introduced an IRQ lock inversion issue. Fix this lock inversion by changing the spin_lock_irq() calls into spin_lock_irqsave() calls in code that can be called either from interrupt context or from thread context. This patch fixes the following lockdep complaint: WARNING: possible irq lock inversion dependency detected 6.12.30-android16-5-maybe-dirty-4k #1 Tainted: G W OE -------------------------------------------------------- kworker/u28:0/12 just changed the state of lock: ffffff881e29dd60 (&hba->clk_gating.lock){-...}-{2:2}, at: ufshcd_release_scsi_cmd+0x60/0x110 but this lock took another, HARDIRQ-unsafe lock in the past: (shost->host_lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(shost->host_lock); local_irq_disable(); lock(&hba->clk_gating.lock); lock(shost->host_lock); <Interrupt> lock(&hba->clk_gating.lock); *** DEADLOCK *** 4 locks held by kworker/u28:0/12: #0: ffffff8800ac6158 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c #1: ffffffc085c93d70 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c #2: ffffff881e29c0e0 (&shost->scan_mutex){+.+.}-{3:3}, at: __scsi_add_device+0x74/0x120 #3: ffffff881960ea00 (&hwq->cq_lock){-...}-{2:2}, at: ufshcd_mcq_poll_cqe_lock+0x28/0x104 the shortest dependencies between 2nd lock and 1st lock: -> (shost->host_lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 SOFTIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba1a98>] scsi_host_alloc.__key+0x0/0x10 ... acquired at: _raw_spin_lock_irqsave+0x5c/0x80 __ufshcd_release+0x78/0x118 ufshcd_send_uic_cmd+0xe4/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 -> (&hba->clk_gating.lock){-...}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_hold+0x34/0x14c ufshcd_send_uic_cmd+0x28/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba6fe8>] ufshcd_init.__key+0x0/0x10 ... acquired at: mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 stack backtrace: CPU: 6 UID: 0 PID: 12 Comm: kworker/u28:0 Tainted: G W OE 6.12.30-android16-5-maybe-dirty-4k #1 ccd4020fe444bdf629efc3b86df6be920b8df7d0 Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Spacecraft board based on MALIBU (DT) Workqueue: async async_run_entry_fn Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 print_irq_inversion_bug+0x2fc/0x304 mark_lock_irq+0x388/0x4fc mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs dd6f385554e109da094ab91d5f7be18625a2222a] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 Cc: Neil Armstrong <[email protected]> Cc: André Draszik <[email protected]> Reviewed-by: Peter Wang <[email protected]> Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") Signed-off-by: Bart Van Assche <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin K. Petersen <[email protected]>
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In the snd_utimer_create() function, if the kasprintf() function return NULL, snd_utimer_put_id() will be called, finally use ida_free() to free the unallocated id 0. the syzkaller reported the following information: ------------[ cut here ]------------ ida_free called for id=0 which is not allocated. WARNING: CPU: 1 PID: 1286 at lib/idr.c:592 ida_free+0x1fd/0x2f0 lib/idr.c:592 Modules linked in: CPU: 1 UID: 0 PID: 1286 Comm: syz-executor164 Not tainted 6.15.8 #3 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-4.fc42 04/01/2014 RIP: 0010:ida_free+0x1fd/0x2f0 lib/idr.c:592 Code: f8 fc 41 83 fc 3e 76 69 e8 70 b2 f8 (...) RSP: 0018:ffffc900007f79c8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 1ffff920000fef3b RCX: ffffffff872176a5 RDX: ffff88800369d200 RSI: 0000000000000000 RDI: ffff88800369d200 RBP: 0000000000000000 R08: ffffffff87ba60a5 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f6f1abc1740(0000) GS:ffff8880d76a0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6f1ad7a784 CR3: 000000007a6e2000 CR4: 00000000000006f0 Call Trace: <TASK> snd_utimer_put_id sound/core/timer.c:2043 [inline] [snd_timer] snd_utimer_create+0x59b/0x6a0 sound/core/timer.c:2184 [snd_timer] snd_utimer_ioctl_create sound/core/timer.c:2202 [inline] [snd_timer] __snd_timer_user_ioctl.isra.0+0x724/0x1340 sound/core/timer.c:2287 [snd_timer] snd_timer_user_ioctl+0x75/0xc0 sound/core/timer.c:2298 [snd_timer] vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x198/0x200 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x7b/0x160 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e [...] The utimer->id should be set properly before the kasprintf() function, ensures the snd_utimer_put_id() function will free the allocated id. Fixes: 3774591 ("ALSA: timer: Introduce virtual userspace-driven timers") Signed-off-by: Dewei Meng <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Takashi Iwai <[email protected]>
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Aug 29, 2025
The QuickI2C ACPI _DSD methods return ICRS and ISUB data with a trailing byte, making the actual length is one more byte than the structs defined. It caused stack-out-of-bounds and kernel crash: kernel: BUG: KASAN: stack-out-of-bounds in quicki2c_acpi_get_dsd_property.constprop.0+0x111/0x1b0 [intel_quicki2c] kernel: Write of size 12 at addr ffff888106d1f900 by task kworker/u33:2/75 kernel: kernel: CPU: 3 UID: 0 PID: 75 Comm: kworker/u33:2 Not tainted 6.16.0+ #3 PREEMPT(voluntary) kernel: Workqueue: async async_run_entry_fn kernel: Call Trace: kernel: <TASK> kernel: dump_stack_lvl+0x76/0xa0 kernel: print_report+0xd1/0x660 kernel: ? __pfx__raw_spin_lock_irqsave+0x10/0x10 kernel: ? __kasan_slab_free+0x5d/0x80 kernel: ? kasan_addr_to_slab+0xd/0xb0 kernel: kasan_report+0xe1/0x120 kernel: ? quicki2c_acpi_get_dsd_property.constprop.0+0x111/0x1b0 [intel_quicki2c] kernel: ? quicki2c_acpi_get_dsd_property.constprop.0+0x111/0x1b0 [intel_quicki2c] kernel: kasan_check_range+0x11c/0x200 kernel: __asan_memcpy+0x3b/0x80 kernel: quicki2c_acpi_get_dsd_property.constprop.0+0x111/0x1b0 [intel_quicki2c] kernel: ? __pfx_quicki2c_acpi_get_dsd_property.constprop.0+0x10/0x10 [intel_quicki2c] kernel: quicki2c_get_acpi_resources+0x237/0x730 [intel_quicki2c] [...] kernel: </TASK> kernel: kernel: The buggy address belongs to stack of task kworker/u33:2/75 kernel: and is located at offset 48 in frame: kernel: quicki2c_get_acpi_resources+0x0/0x730 [intel_quicki2c] kernel: kernel: This frame has 3 objects: kernel: [32, 36) 'hid_desc_addr' kernel: [48, 59) 'i2c_param' kernel: [80, 224) 'i2c_config' ACPI DSD methods return: \_SB.PC00.THC0.ICRS Buffer 000000003fdc947b 001 Len 0C = 0A 00 80 1A 06 00 00 00 00 00 00 00 \_SB.PC00.THC0.ISUB Buffer 00000000f2fcbdc4 001 Len 91 = 00 00 00 00 00 00 00 00 00 00 00 00 Adding reserved padding to quicki2c_subip_acpi_parameter/config. Fixes: 5282e45 ("HID: intel-thc-hid: intel-quicki2c: Add THC QuickI2C ACPI interfaces") Signed-off-by: Aaron Ma <[email protected]> Reviewed-by: Even Xu <[email protected]> Tested-by: Even Xu <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>
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…C regs save Improper use of secondary pointer (&dev->i2c_subip_regs) caused kernel crash and out-of-bounds error: BUG: KASAN: slab-out-of-bounds in _regmap_bulk_read+0x449/0x510 Write of size 4 at addr ffff888136005dc0 by task kworker/u33:5/5107 CPU: 3 UID: 0 PID: 5107 Comm: kworker/u33:5 Not tainted 6.16.0+ #3 PREEMPT(voluntary) Workqueue: async async_run_entry_fn Call Trace: <TASK> dump_stack_lvl+0x76/0xa0 print_report+0xd1/0x660 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? kasan_complete_mode_report_info+0x26/0x200 kasan_report+0xe1/0x120 ? _regmap_bulk_read+0x449/0x510 ? _regmap_bulk_read+0x449/0x510 __asan_report_store4_noabort+0x17/0x30 _regmap_bulk_read+0x449/0x510 ? __pfx__regmap_bulk_read+0x10/0x10 regmap_bulk_read+0x270/0x3d0 pio_complete+0x1ee/0x2c0 [intel_thc] ? __pfx_pio_complete+0x10/0x10 [intel_thc] ? __pfx_pio_wait+0x10/0x10 [intel_thc] ? regmap_update_bits_base+0x13b/0x1f0 thc_i2c_subip_pio_read+0x117/0x270 [intel_thc] thc_i2c_subip_regs_save+0xc2/0x140 [intel_thc] ? __pfx_thc_i2c_subip_regs_save+0x10/0x10 [intel_thc] [...] The buggy address belongs to the object at ffff888136005d00 which belongs to the cache kmalloc-rnd-12-192 of size 192 The buggy address is located 0 bytes to the right of allocated 192-byte region [ffff888136005d00, ffff888136005dc0) Replaced with direct array indexing (&dev->i2c_subip_regs[i]) to ensure safe memory access. Fixes: 4228966 ("HID: intel-thc-hid: intel-thc: Add THC I2C config interfaces") Signed-off-by: Aaron Ma <[email protected]> Reviewed-by: Even Xu <[email protected]> Tested-by: Even Xu <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>
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A malicious HID device can trigger a slab out-of-bounds during mt_report_fixup() by passing in report descriptor smaller than 607 bytes. mt_report_fixup() attempts to patch byte offset 607 of the descriptor with 0x25 by first checking if byte offset 607 is 0x15 however it lacks bounds checks to verify if the descriptor is big enough before conducting this check. Fix this bug by ensuring the descriptor size is at least 608 bytes before accessing it. Below is the KASAN splat after the out of bounds access happens: [ 13.671954] ================================================================== [ 13.672667] BUG: KASAN: slab-out-of-bounds in mt_report_fixup+0x103/0x110 [ 13.673297] Read of size 1 at addr ffff888103df39df by task kworker/0:1/10 [ 13.673297] [ 13.673297] CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.15.0-00005-gec5d573d83f4-dirty #3 [ 13.673297] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/04 [ 13.673297] Call Trace: [ 13.673297] <TASK> [ 13.673297] dump_stack_lvl+0x5f/0x80 [ 13.673297] print_report+0xd1/0x660 [ 13.673297] kasan_report+0xe5/0x120 [ 13.673297] __asan_report_load1_noabort+0x18/0x20 [ 13.673297] mt_report_fixup+0x103/0x110 [ 13.673297] hid_open_report+0x1ef/0x810 [ 13.673297] mt_probe+0x422/0x960 [ 13.673297] hid_device_probe+0x2e2/0x6f0 [ 13.673297] really_probe+0x1c6/0x6b0 [ 13.673297] __driver_probe_device+0x24f/0x310 [ 13.673297] driver_probe_device+0x4e/0x220 [ 13.673297] __device_attach_driver+0x169/0x320 [ 13.673297] bus_for_each_drv+0x11d/0x1b0 [ 13.673297] __device_attach+0x1b8/0x3e0 [ 13.673297] device_initial_probe+0x12/0x20 [ 13.673297] bus_probe_device+0x13d/0x180 [ 13.673297] device_add+0xe3a/0x1670 [ 13.673297] hid_add_device+0x31d/0xa40 [...] Fixes: c8000de ("HID: multitouch: Add support for GT7868Q") Cc: [email protected] Signed-off-by: Qasim Ijaz <[email protected]> Reviewed-by: Jiri Slaby <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>
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These iterations require the read lock, otherwise RCU lockdep will splat: ============================= WARNING: suspicious RCU usage 6.17.0-rc3-00014-g31419c045d64 #6 Tainted: G O ----------------------------- drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 5 locks held by rtcwake/547: #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98 stack backtrace: CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G O 6.17.0-rc3-00014-g31419c045d64 #6 VOLUNTARY Tainted: [O]=OOT_MODULE Stack: 223721b3a80 6089eac6 00000001 00000001 ffffff00 6089eac6 00000535 6086e528 721b3ac0 6003c294 00000000 60031fc0 Call Trace: [<600407ed>] show_stack+0x10e/0x127 [<6003c294>] dump_stack_lvl+0x77/0xc6 [<6003c2fd>] dump_stack+0x1a/0x20 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e [<603d980f>] device_suspend+0x528/0x541 [<603da24b>] dpm_suspend+0x1a2/0x267 [<603da837>] dpm_suspend_start+0x5d/0x72 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736 [...] Add the fourth argument to the iteration to annotate this and avoid the splat. Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents") Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children") Signed-off-by: Johannes Berg <[email protected]> Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid Signed-off-by: Rafael J. Wysocki <[email protected]>
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When a large VM, specifically one that holds a significant number of PTEs, gets abruptly destroyed, the following warning is seen during the page-table walk: sched: CPU 0 need_resched set for > 100018840 ns (100 ticks) without schedule CPU: 0 UID: 0 PID: 9617 Comm: kvm_page_table_ Tainted: G O 6.16.0-smp-DEV #3 NONE Tainted: [O]=OOT_MODULE Call trace: show_stack+0x20/0x38 (C) dump_stack_lvl+0x3c/0xb8 dump_stack+0x18/0x30 resched_latency_warn+0x7c/0x88 sched_tick+0x1c4/0x268 update_process_times+0xa8/0xd8 tick_nohz_handler+0xc8/0x168 __hrtimer_run_queues+0x11c/0x338 hrtimer_interrupt+0x104/0x308 arch_timer_handler_phys+0x40/0x58 handle_percpu_devid_irq+0x8c/0x1b0 generic_handle_domain_irq+0x48/0x78 gic_handle_irq+0x1b8/0x408 call_on_irq_stack+0x24/0x30 do_interrupt_handler+0x54/0x78 el1_interrupt+0x44/0x88 el1h_64_irq_handler+0x18/0x28 el1h_64_irq+0x84/0x88 stage2_free_walker+0x30/0xa0 (P) __kvm_pgtable_walk+0x11c/0x258 __kvm_pgtable_walk+0x180/0x258 __kvm_pgtable_walk+0x180/0x258 __kvm_pgtable_walk+0x180/0x258 kvm_pgtable_walk+0xc4/0x140 kvm_pgtable_stage2_destroy+0x5c/0xf0 kvm_free_stage2_pgd+0x6c/0xe8 kvm_uninit_stage2_mmu+0x24/0x48 kvm_arch_flush_shadow_all+0x80/0xa0 kvm_mmu_notifier_release+0x38/0x78 __mmu_notifier_release+0x15c/0x250 exit_mmap+0x68/0x400 __mmput+0x38/0x1c8 mmput+0x30/0x68 exit_mm+0xd4/0x198 do_exit+0x1a4/0xb00 do_group_exit+0x8c/0x120 get_signal+0x6d4/0x778 do_signal+0x90/0x718 do_notify_resume+0x70/0x170 el0_svc+0x74/0xd8 el0t_64_sync_handler+0x60/0xc8 el0t_64_sync+0x1b0/0x1b8 The warning is seen majorly on the host kernels that are configured not to force-preempt, such as CONFIG_PREEMPT_NONE=y. To avoid this, instead of walking the entire page-table in one go, split it into smaller ranges, by checking for cond_resched() between each range. Since the path is executed during VM destruction, after the page-table structure is unlinked from the KVM MMU, relying on cond_resched_rwlock_write() isn't necessary. Signed-off-by: Raghavendra Rao Ananta <[email protected]> Suggested-by: Oliver Upton <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Oliver Upton <[email protected]>
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When the "proxy" option is enabled on a VXLAN device, the device will suppress ARP requests and IPv6 Neighbor Solicitation messages if it is able to reply on behalf of the remote host. That is, if a matching and valid neighbor entry is configured on the VXLAN device whose MAC address is not behind the "any" remote (0.0.0.0 / ::). The code currently assumes that the FDB entry for the neighbor's MAC address points to a valid remote destination, but this is incorrect if the entry is associated with an FDB nexthop group. This can result in a NPD [1][3] which can be reproduced using [2][4]. Fix by checking that the remote destination exists before dereferencing it. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 RIP: 0010:vxlan_xmit+0xb58/0x15f0 [...] Call Trace: <TASK> dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 packet_sendmsg+0x113a/0x1850 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [2] #!/bin/bash ip address add 192.0.2.1/32 dev lo ip nexthop add id 1 via 192.0.2.2 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 4789 proxy ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10 arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3 [3] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014 RIP: 0010:vxlan_xmit+0x803/0x1600 [...] Call Trace: <TASK> dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 ip6_finish_output2+0x210/0x6c0 ip6_finish_output+0x1af/0x2b0 ip6_mr_output+0x92/0x3e0 ip6_send_skb+0x30/0x90 rawv6_sendmsg+0xe6e/0x12e0 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f383422ec77 [4] #!/bin/bash ip address add 2001:db8:1::1/128 dev lo ip nexthop add id 1 via 2001:db8:1::1 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10 ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0 Fixes: 1274e1c ("vxlan: ecmp support for mac fdb entries") Reviewed-by: Petr Machata <[email protected]> Signed-off-by: Ido Schimmel <[email protected]> Reviewed-by: Nikolay Aleksandrov <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
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Ido Schimmel says:
====================
vxlan: Fix NPDs when using nexthop objects
With FDB nexthop groups, VXLAN FDB entries do not necessarily point to
a remote destination but rather to an FDB nexthop group. This means that
first_remote_{rcu,rtnl}() can return NULL and a few places in the driver
were not ready for that, resulting in NULL pointer dereferences.
Patches #1-#2 fix these NPDs.
Note that vxlan_fdb_find_uc() still dereferences the remote returned by
first_remote_rcu() without checking that it is not NULL, but this
function is only invoked by a single driver which vetoes the creation of
FDB nexthop groups. I will patch this in net-next to make the code less
fragile.
Patch #3 adds a selftests which exercises these code paths and tests
basic Tx functionality with FDB nexthop groups. I verified that the test
crashes the kernel without the first two patches.
====================
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
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When transmitting a PTP frame which is timestamp using 2 step, the following warning appears if CONFIG_PROVE_LOCKING is enabled: ============================= [ BUG: Invalid wait context ] 6.17.0-rc1-00326-ge6160462704e torvalds#427 Not tainted ----------------------------- ptp4l/119 is trying to lock: c2a44ed4 (&vsc8531->ts_lock){+.+.}-{3:3}, at: vsc85xx_txtstamp+0x50/0xac other info that might help us debug this: context-{4:4} 4 locks held by ptp4l/119: #0: c145f068 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x58/0x1440 #1: c29df974 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x5c4/0x1440 #2: c2aaaad0 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x108/0x350 #3: c2aac170 (&lan966x->tx_lock){+.-.}-{2:2}, at: lan966x_port_xmit+0xd0/0x350 stack backtrace: CPU: 0 UID: 0 PID: 119 Comm: ptp4l Not tainted 6.17.0-rc1-00326-ge6160462704e torvalds#427 NONE Hardware name: Generic DT based system Call trace: unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x7c/0xac dump_stack_lvl from __lock_acquire+0x8e8/0x29dc __lock_acquire from lock_acquire+0x108/0x38c lock_acquire from __mutex_lock+0xb0/0xe78 __mutex_lock from mutex_lock_nested+0x1c/0x24 mutex_lock_nested from vsc85xx_txtstamp+0x50/0xac vsc85xx_txtstamp from lan966x_fdma_xmit+0xd8/0x3a8 lan966x_fdma_xmit from lan966x_port_xmit+0x1bc/0x350 lan966x_port_xmit from dev_hard_start_xmit+0xc8/0x2c0 dev_hard_start_xmit from sch_direct_xmit+0x8c/0x350 sch_direct_xmit from __dev_queue_xmit+0x680/0x1440 __dev_queue_xmit from packet_sendmsg+0xfa4/0x1568 packet_sendmsg from __sys_sendto+0x110/0x19c __sys_sendto from sys_send+0x18/0x20 sys_send from ret_fast_syscall+0x0/0x1c Exception stack(0xf0b05fa8 to 0xf0b05ff0) 5fa0: 00000001 0000000 0000000 0004b47a 0000003a 00000000 5fc0: 00000001 0000000 00000000 00000121 0004af58 00044874 00000000 00000000 5fe0: 00000001 bee9d420 00025a10 b6e75c7c So, instead of using the ts_lock for tx_queue, use the spinlock that skb_buff_head has. Reviewed-by: Vadim Fedorenko <[email protected]> Fixes: 7d272e6 ("net: phy: mscc: timestamping and PHC support") Signed-off-by: Horatiu Vultur <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
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Problem description
===================
Lockdep reports a possible circular locking dependency (AB/BA) between
&pl->state_mutex and &phy->lock, as follows.
phylink_resolve() // acquires &pl->state_mutex
-> phylink_major_config()
-> phy_config_inband() // acquires &pl->phydev->lock
whereas all the other call sites where &pl->state_mutex and
&pl->phydev->lock have the locking scheme reversed. Everywhere else,
&pl->phydev->lock is acquired at the top level, and &pl->state_mutex at
the lower level. A clear example is phylink_bringup_phy().
The outlier is the newly introduced phy_config_inband() and the existing
lock order is the correct one. To understand why it cannot be the other
way around, it is sufficient to consider phylink_phy_change(), phylink's
callback from the PHY device's phy->phy_link_change() virtual method,
invoked by the PHY state machine.
phy_link_up() and phy_link_down(), the (indirect) callers of
phylink_phy_change(), are called with &phydev->lock acquired.
Then phylink_phy_change() acquires its own &pl->state_mutex, to
serialize changes made to its pl->phy_state and pl->link_config.
So all other instances of &pl->state_mutex and &phydev->lock must be
consistent with this order.
Problem impact
==============
I think the kernel runs a serious deadlock risk if an existing
phylink_resolve() thread, which results in a phy_config_inband() call,
is concurrent with a phy_link_up() or phy_link_down() call, which will
deadlock on &pl->state_mutex in phylink_phy_change(). Practically
speaking, the impact may be limited by the slow speed of the medium
auto-negotiation protocol, which makes it unlikely for the current state
to still be unresolved when a new one is detected, but I think the
problem is there. Nonetheless, the problem was discovered using lockdep.
Proposed solution
=================
Practically speaking, the phy_config_inband() requirement of having
phydev->lock acquired must transfer to the caller (phylink is the only
caller). There, it must bubble up until immediately before
&pl->state_mutex is acquired, for the cases where that takes place.
Solution details, considerations, notes
=======================================
This is the phy_config_inband() call graph:
sfp_upstream_ops :: connect_phy()
|
v
phylink_sfp_connect_phy()
|
v
phylink_sfp_config_phy()
|
| sfp_upstream_ops :: module_insert()
| |
| v
| phylink_sfp_module_insert()
| |
| | sfp_upstream_ops :: module_start()
| | |
| | v
| | phylink_sfp_module_start()
| | |
| v v
| phylink_sfp_config_optical()
phylink_start() | |
| phylink_resume() v v
| | phylink_sfp_set_config()
| | |
v v v
phylink_mac_initial_config()
| phylink_resolve()
| | phylink_ethtool_ksettings_set()
v v v
phylink_major_config()
|
v
phy_config_inband()
phylink_major_config() caller #1, phylink_mac_initial_config(), does not
acquire &pl->state_mutex nor do its callers. It must acquire
&pl->phydev->lock prior to calling phylink_major_config().
phylink_major_config() caller #2, phylink_resolve() acquires
&pl->state_mutex, thus also needs to acquire &pl->phydev->lock.
phylink_major_config() caller #3, phylink_ethtool_ksettings_set(), is
completely uninteresting, because it only calls phylink_major_config()
if pl->phydev is NULL (otherwise it calls phy_ethtool_ksettings_set()).
We need to change nothing there.
Other solutions
===============
The lock inversion between &pl->state_mutex and &pl->phydev->lock has
occurred at least once before, as seen in commit c718af2 ("net:
phylink: fix ethtool -A with attached PHYs"). The solution there was to
simply not call phy_set_asym_pause() under the &pl->state_mutex. That
cannot be extended to our case though, where the phy_config_inband()
call is much deeper inside the &pl->state_mutex section.
Fixes: 5fd0f1a ("net: phylink: add negotiation of in-band capabilities")
Signed-off-by: Vladimir Oltean <[email protected]>
Reviewed-by: Russell King (Oracle) <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
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…ux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 changes for 6.17, round #3 - Invalidate nested MMUs upon freeing the PGD to avoid WARNs when visiting from an MMU notifier - Fixes to the TLB match process and TLB invalidation range for managing the VCNR pseudo-TLB - Prevent SPE from erroneously profiling guests due to UNKNOWN reset values in PMSCR_EL1 - Fix save/restore of host MDCR_EL2 to account for eagerly programming at vcpu_load() on VHE systems - Correct lock ordering when dealing with VGIC LPIs, avoiding scenarios where an xarray's spinlock was nested with a *raw* spinlock - Permit stage-2 read permission aborts which are possible in the case of NV depending on the guest hypervisor's stage-2 translation - Call raw_spin_unlock() instead of the internal spinlock API - Fix parameter ordering when assigning VBAR_EL1
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Sep 25, 2025
This fixes the following UAF caused by not properly locking hdev when processing HCI_EV_NUM_COMP_PKTS: BUG: KASAN: slab-use-after-free in hci_conn_tx_dequeue+0x1be/0x220 net/bluetooth/hci_conn.c:3036 Read of size 4 at addr ffff8880740f0940 by task kworker/u11:0/54 CPU: 1 UID: 0 PID: 54 Comm: kworker/u11:0 Not tainted 6.16.0-rc7 #3 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Workqueue: hci1 hci_rx_work Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x230 mm/kasan/report.c:480 kasan_report+0x118/0x150 mm/kasan/report.c:593 hci_conn_tx_dequeue+0x1be/0x220 net/bluetooth/hci_conn.c:3036 hci_num_comp_pkts_evt+0x1c8/0xa50 net/bluetooth/hci_event.c:4404 hci_event_func net/bluetooth/hci_event.c:7477 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7531 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 </TASK> Allocated by task 54: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] __hci_conn_add+0x233/0x1b30 net/bluetooth/hci_conn.c:939 le_conn_complete_evt+0x3d6/0x1220 net/bluetooth/hci_event.c:5628 hci_le_enh_conn_complete_evt+0x189/0x470 net/bluetooth/hci_event.c:5794 hci_event_func net/bluetooth/hci_event.c:7474 [inline] hci_event_packet+0x78c/0x1200 net/bluetooth/hci_event.c:7531 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 Freed by task 9572: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 device_release+0x9c/0x1c0 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 hci_conn_cleanup net/bluetooth/hci_conn.c:175 [inline] hci_conn_del+0x8ff/0xcb0 net/bluetooth/hci_conn.c:1173 hci_abort_conn_sync+0x5d1/0xdf0 net/bluetooth/hci_sync.c:5689 hci_cmd_sync_work+0x210/0x3a0 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 Fixes: 134f4b3 ("Bluetooth: add support for skb TX SND/COMPLETION timestamping") Reported-by: Junvyyang, Tencent Zhuque Lab <[email protected]> Signed-off-by: Luiz Augusto von Dentz <[email protected]>
kdave
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This fixes the following UFA in hci_acl_create_conn_sync where a connection still pending is command submission (conn->state == BT_OPEN) maybe freed, also since this also can happen with the likes of hci_le_create_conn_sync fix it as well: BUG: KASAN: slab-use-after-free in hci_acl_create_conn_sync+0x5ef/0x790 net/bluetooth/hci_sync.c:6861 Write of size 2 at addr ffff88805ffcc038 by task kworker/u11:2/9541 CPU: 1 UID: 0 PID: 9541 Comm: kworker/u11:2 Not tainted 6.16.0-rc7 #3 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Workqueue: hci3 hci_cmd_sync_work Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x230 mm/kasan/report.c:480 kasan_report+0x118/0x150 mm/kasan/report.c:593 hci_acl_create_conn_sync+0x5ef/0x790 net/bluetooth/hci_sync.c:6861 hci_cmd_sync_work+0x210/0x3a0 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 </TASK> Allocated by task 123736: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] __hci_conn_add+0x233/0x1b30 net/bluetooth/hci_conn.c:939 hci_conn_add_unset net/bluetooth/hci_conn.c:1051 [inline] hci_connect_acl+0x16c/0x4e0 net/bluetooth/hci_conn.c:1634 pair_device+0x418/0xa70 net/bluetooth/mgmt.c:3556 hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719 hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 sock_write_iter+0x258/0x330 net/socket.c:1131 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x54b/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 103680: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 device_release+0x9c/0x1c0 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 hci_conn_cleanup net/bluetooth/hci_conn.c:175 [inline] hci_conn_del+0x8ff/0xcb0 net/bluetooth/hci_conn.c:1173 hci_conn_complete_evt+0x3c7/0x1040 net/bluetooth/hci_event.c:3199 hci_event_func net/bluetooth/hci_event.c:7477 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7531 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 insert_work+0x3d/0x330 kernel/workqueue.c:2183 __queue_work+0xbd9/0xfe0 kernel/workqueue.c:2345 queue_delayed_work_on+0x18b/0x280 kernel/workqueue.c:2561 pairing_complete+0x1e7/0x2b0 net/bluetooth/mgmt.c:3451 pairing_complete_cb+0x1ac/0x230 net/bluetooth/mgmt.c:3487 hci_connect_cfm include/net/bluetooth/hci_core.h:2064 [inline] hci_conn_failed+0x24d/0x310 net/bluetooth/hci_conn.c:1275 hci_conn_complete_evt+0x3c7/0x1040 net/bluetooth/hci_event.c:3199 hci_event_func net/bluetooth/hci_event.c:7477 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7531 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 Fixes: aef2aa4 ("Bluetooth: hci_event: Fix creating hci_conn object on error status") Reported-by: Junvyyang, Tencent Zhuque Lab <[email protected]> Signed-off-by: Luiz Augusto von Dentz <[email protected]>
kdave
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Ido Schimmel says: ==================== nexthop: Various fixes Patch #1 fixes a NPD that was recently reported by syzbot. Patch #2 fixes an issue in the existing FIB nexthop selftest. Patch #3 extends the selftest with test cases for the bug that was fixed in the first patch. ==================== Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
kdave
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Sep 30, 2025
We check the version of SPE twice, and we'll add one more check in the next commit so factor out a macro to do this. Change the #3 magic number to the actual SPE version define (V1p2) to make it more readable. No functional changes intended. Tested-by: Leo Yan <[email protected]> Reviewed-by: Leo Yan <[email protected]> Signed-off-by: James Clark <[email protected]> Signed-off-by: Will Deacon <[email protected]>
kdave
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The test starts a workload and then opens events. If the events fail
to open, for example because of perf_event_paranoid, the gopipe of the
workload is leaked and the file descriptor leak check fails when the
test exits. To avoid this cancel the workload when opening the events
fails.
Before:
```
$ perf test -vv 7
7: PERF_RECORD_* events & perf_sample fields:
--- start ---
test child forked, pid 1189568
Using CPUID GenuineIntel-6-B7-1
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8
sys_perf_event_open failed, error -13
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
exclude_kernel 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8
sys_perf_event_open failed, error -13
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/)
disabled 1
exclude_kernel 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3
Attempt to add: software/cpu-clock/
..after resolving event: software/config=0/
cpu-clock -> software/cpu-clock/
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
config 0x9 (PERF_COUNT_SW_DUMMY)
sample_type IP|TID|TIME|CPU
read_format ID|LOST
disabled 1
inherit 1
mmap 1
comm 1
enable_on_exec 1
task 1
sample_id_all 1
mmap2 1
comm_exec 1
ksymbol 1
bpf_event 1
{ wakeup_events, wakeup_watermark } 1
------------------------------------------------------------
sys_perf_event_open: pid 1189569 cpu 0 group_fd -1 flags 0x8
sys_perf_event_open failed, error -13
perf_evlist__open: Permission denied
---- end(-2) ----
Leak of file descriptor 6 that opened: 'pipe:[14200347]'
---- unexpected signal (6) ----
iFailed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
Failed to read build ID for //anon
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#0 0x565358f6666e in child_test_sig_handler builtin-test.c:311
#1 0x7f29ce849df0 in __restore_rt libc_sigaction.c:0
#2 0x7f29ce89e95c in __pthread_kill_implementation pthread_kill.c:44
#3 0x7f29ce849cc2 in raise raise.c:27
#4 0x7f29ce8324ac in abort abort.c:81
#5 0x565358f662d4 in check_leaks builtin-test.c:226
#6 0x565358f6682e in run_test_child builtin-test.c:344
#7 0x565358ef7121 in start_command run-command.c:128
#8 0x565358f67273 in start_test builtin-test.c:545
#9 0x565358f6771d in __cmd_test builtin-test.c:647
#10 0x565358f682bd in cmd_test builtin-test.c:849
torvalds#11 0x565358ee5ded in run_builtin perf.c:349
torvalds#12 0x565358ee6085 in handle_internal_command perf.c:401
torvalds#13 0x565358ee61de in run_argv perf.c:448
torvalds#14 0x565358ee6527 in main perf.c:555
torvalds#15 0x7f29ce833ca8 in __libc_start_call_main libc_start_call_main.h:74
torvalds#16 0x7f29ce833d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
torvalds#17 0x565358e391c1 in _start perf[851c1]
7: PERF_RECORD_* events & perf_sample fields : FAILED!
```
After:
```
$ perf test 7
7: PERF_RECORD_* events & perf_sample fields : Skip (permissions)
```
Fixes: 16d00fe ("perf tests: Move test__PERF_RECORD into separate object")
Signed-off-by: Ian Rogers <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Chun-Tse Shao <[email protected]>
Cc: Howard Chu <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
kdave
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Don't emulate branch instructions, e.g. CALL/RET/JMP etc., that are affected by Shadow Stacks and/or Indirect Branch Tracking when said features are enabled in the guest, as fully emulating CET would require significant complexity for no practical benefit (KVM shouldn't need to emulate branch instructions on modern hosts). Simply doing nothing isn't an option as that would allow a malicious entity to subvert CET protections via the emulator. To detect instructions that are subject to IBT or affect IBT state, use the existing IsBranch flag along with the source operand type to detect indirect branches, and the existing NearBranch flag to detect far JMPs and CALLs, all of which are effectively indirect. Explicitly check for emulation of IRET, FAR RET (IMM), and SYSEXIT (the ret-like far branches) instead of adding another flag, e.g. IsRet, as it's unlikely the emulator will ever need to check for return-like instructions outside of this one specific flow. Use an allow-list instead of a deny-list because (a) it's a shorter list and (b) so that a missed entry gets a false positive, not a false negative (i.e. reject emulation instead of clobbering CET state). For Shadow Stacks, explicitly track instructions that directly affect the current SSP, as KVM's emulator doesn't have existing flags that can be used to precisely detect such instructions. Alternatively, the em_xxx() helpers could directly check for ShadowStack interactions, but using a dedicated flag is arguably easier to audit, and allows for handling both IBT and SHSTK in one fell swoop. Note! On far transfers, do NOT consult the current privilege level and instead treat SHSTK/IBT as being enabled if they're enabled for User *or* Supervisor mode. On inter-privilege level far transfers, SHSTK and IBT can be in play for the target privilege level, i.e. checking the current privilege could get a false negative, and KVM doesn't know the target privilege level until emulation gets under way. Note #2, FAR JMP from 64-bit mode to compatibility mode interacts with the current SSP, but only to ensure SSP[63:32] == 0. Don't tag FAR JMP as SHSTK, which would be rather confusing and would result in FAR JMP being rejected unnecessarily the vast majority of the time (ignoring that it's unlikely to ever be emulated). A future commit will add the #GP(0) check for the specific FAR JMP scenario. Note #3, task switches also modify SSP and so need to be rejected. That too will be addressed in a future commit. Suggested-by: Chao Gao <[email protected]> Originally-by: Yang Weijiang <[email protected]> Cc: Mathias Krause <[email protected]> Cc: John Allen <[email protected]> Cc: Rick Edgecombe <[email protected]> Reviewed-by: Chao Gao <[email protected]> Reviewed-by: Binbin Wu <[email protected]> Reviewed-by: Xiaoyao Li <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
kdave
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Before disabling SR-IOV via config space accesses to the parent PF, sriov_disable() first removes the PCI devices representing the VFs. Since commit 9d16947 ("PCI: Add global pci_lock_rescan_remove()") such removal operations are serialized against concurrent remove and rescan using the pci_rescan_remove_lock. No such locking was ever added in sriov_disable() however. In particular when commit 18f9e9d ("PCI/IOV: Factor out sriov_add_vfs()") factored out the PCI device removal into sriov_del_vfs() there was still no locking around the pci_iov_remove_virtfn() calls. On s390 the lack of serialization in sriov_disable() may cause double remove and list corruption with the below (amended) trace being observed: PSW: 0704c00180000000 0000000c914e4b38 (klist_put+56) GPRS: 000003800313fb48 0000000000000000 0000000100000001 0000000000000001 00000000f9b520a8 0000000000000000 0000000000002fbd 00000000f4cc9480 0000000000000001 0000000000000000 0000000000000000 0000000180692828 00000000818e8000 000003800313fe2c 000003800313fb20 000003800313fad8 #0 [3800313fb20] device_del at c9158ad5c #1 [3800313fb88] pci_remove_bus_device at c915105ba #2 [3800313fbd0] pci_iov_remove_virtfn at c9152f198 #3 [3800313fc28] zpci_iov_remove_virtfn at c90fb67c0 #4 [3800313fc60] zpci_bus_remove_device at c90fb6104 #5 [3800313fca0] __zpci_event_availability at c90fb3dca #6 [3800313fd08] chsc_process_sei_nt0 at c918fe4a2 #7 [3800313fd60] crw_collect_info at c91905822 #8 [3800313fe10] kthread at c90feb390 #9 [3800313fe68] __ret_from_fork at c90f6aa64 #10 [3800313fe98] ret_from_fork at c9194f3f2. This is because in addition to sriov_disable() removing the VFs, the platform also generates hot-unplug events for the VFs. This being the reverse operation to the hotplug events generated by sriov_enable() and handled via pdev->no_vf_scan. And while the event processing takes pci_rescan_remove_lock and checks whether the struct pci_dev still exists, the lack of synchronization makes this checking racy. Other races may also be possible of course though given that this lack of locking persisted so long observable races seem very rare. Even on s390 the list corruption was only observed with certain devices since the platform events are only triggered by config accesses after the removal, so as long as the removal finished synchronously they would not race. Either way the locking is missing so fix this by adding it to the sriov_del_vfs() helper. Just like PCI rescan-remove, locking is also missing in sriov_add_vfs() including for the error case where pci_stop_and_remove_bus_device() is called without the PCI rescan-remove lock being held. Even in the non-error case, adding new PCI devices and buses should be serialized via the PCI rescan-remove lock. Add the necessary locking. Fixes: 18f9e9d ("PCI/IOV: Factor out sriov_add_vfs()") Signed-off-by: Niklas Schnelle <[email protected]> Signed-off-by: Bjorn Helgaas <[email protected]> Reviewed-by: Benjamin Block <[email protected]> Reviewed-by: Farhan Ali <[email protected]> Reviewed-by: Julian Ruess <[email protected]> Cc: [email protected] Link: https://patch.msgid.link/[email protected]
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Oct 13, 2025
The ns_bpf_qdisc selftest triggers a kernel panic: Oops[#1]: CPU 0 Unable to handle kernel paging request at virtual address 0000000000741d58, era == 90000000851b5ac0, ra == 90000000851b5aa4 CPU: 0 UID: 0 PID: 449 Comm: test_progs Tainted: G OE 6.16.0+ #3 PREEMPT(full) Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022 pc 90000000851b5ac0 ra 90000000851b5aa4 tp 90000001076b8000 sp 90000001076bb600 a0 0000000000741ce8 a1 0000000000000001 a2 90000001076bb5c0 a3 0000000000000008 a4 90000001004c4620 a5 9000000100741ce8 a6 0000000000000000 a7 0100000000000000 t0 0000000000000010 t1 0000000000000000 t2 9000000104d24d30 t3 0000000000000001 t4 4f2317da8a7e08c4 t5 fffffefffc002f00 t6 90000001004c4620 t7 ffffffffc61c5b3d t8 0000000000000000 u0 0000000000000001 s9 0000000000000050 s0 90000001075bc800 s1 0000000000000040 s2 900000010597c400 s3 0000000000000008 s4 90000001075bc880 s5 90000001075bc8f0 s6 0000000000000000 s7 0000000000741ce8 s8 0000000000000000 ra: 90000000851b5aa4 __qdisc_run+0xac/0x8d8 ERA: 90000000851b5ac0 __qdisc_run+0xc8/0x8d8 CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) PRMD: 00000004 (PPLV0 +PIE -PWE) EUEN: 00000007 (+FPE +SXE +ASXE -BTE) ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7) ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0) BADV: 0000000000741d58 PRID: 0014c010 (Loongson-64bit, Loongson-3A5000) Modules linked in: bpf_testmod(OE) [last unloaded: bpf_testmod(OE)] Process test_progs (pid: 449, threadinfo=000000009af02b3a, task=00000000e9ba4956) Stack : 0000000000000000 90000001075bc8ac 90000000869524a8 9000000100741ce8 90000001075bc800 9000000100415300 90000001075bc8ac 0000000000000000 900000010597c400 900000008694a000 0000000000000000 9000000105b59000 90000001075bc800 9000000100741ce8 0000000000000050 900000008513000c 9000000086936000 0000000100094d4c fffffff400676208 0000000000000000 9000000105b59000 900000008694a000 9000000086bf0dc0 9000000105b59000 9000000086bf0d68 9000000085147010 90000001075be788 0000000000000000 9000000086bf0f98 0000000000000001 0000000000000010 9000000006015840 0000000000000000 9000000086be6c40 0000000000000000 0000000000000000 0000000000000000 4f2317da8a7e08c4 0000000000000101 4f2317da8a7e08c4 ... Call Trace: [<90000000851b5ac0>] __qdisc_run+0xc8/0x8d8 [<9000000085130008>] __dev_queue_xmit+0x578/0x10f0 [<90000000853701c0>] ip6_finish_output2+0x2f0/0x950 [<9000000085374bc8>] ip6_finish_output+0x2b8/0x448 [<9000000085370b24>] ip6_xmit+0x304/0x858 [<90000000853c4438>] inet6_csk_xmit+0x100/0x170 [<90000000852b32f0>] __tcp_transmit_skb+0x490/0xdd0 [<90000000852b47fc>] tcp_connect+0xbcc/0x1168 [<90000000853b9088>] tcp_v6_connect+0x580/0x8a0 [<90000000852e7738>] __inet_stream_connect+0x170/0x480 [<90000000852e7a98>] inet_stream_connect+0x50/0x88 [<90000000850f2814>] __sys_connect+0xe4/0x110 [<90000000850f2858>] sys_connect+0x18/0x28 [<9000000085520c94>] do_syscall+0x94/0x1a0 [<9000000083df1fb8>] handle_syscall+0xb8/0x158 Code: 4001ad80 2400873 2400832d <240073cc> 001137ff 001133ff 6407b41f 001503cc 0280041d ---[ end trace 0000000000000000 ]--- The bpf_fifo_dequeue prog returns a skb which is a pointer. The pointer is treated as a 32bit value and sign extend to 64bit in epilogue. This behavior is right for most bpf prog types but wrong for struct ops which requires LoongArch ABI. So let's sign extend struct ops return values according to the LoongArch ABI ([1]) and return value spec in function model. [1]: https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html Cc: [email protected] Fixes: 6abf17d ("LoongArch: BPF: Add struct ops support for trampoline") Signed-off-by: Hengqi Chen <[email protected]> Signed-off-by: Huacai Chen <[email protected]>
kdave
pushed a commit
that referenced
this pull request
Oct 16, 2025
Since blamed commit, unregister_netdevice_many_notify() takes the netdev
mutex if the device needs it.
If the device list is too long, this will lock more device mutexes than
lockdep can handle:
unshare -n \
bash -c 'for i in $(seq 1 100);do ip link add foo$i type dummy;done'
BUG: MAX_LOCK_DEPTH too low!
turning off the locking correctness validator.
depth: 48 max: 48!
48 locks held by kworker/u16:1/69:
#0: ..148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work
#1: ..d40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work
#2: ..bd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net
#3: ..aa8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch
#4: ..cb0 (&dev_instance_lock_key#3){+.+.}-{4:4}, at: unregister_netdevice_many_notify
[..]
Add a helper to close and then unlock a list of net_devices.
Devices that are not up have to be skipped - netif_close_many always
removes them from the list without any other actions taken, so they'd
remain in locked state.
Close devices whenever we've used up half of the tracking slots or we
processed entire list without hitting the limit.
Fixes: 7e4d784 ("net: hold netdev instance lock during rtnetlink operations")
Signed-off-by: Florian Westphal <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
kdave
pushed a commit
that referenced
this pull request
Oct 20, 2025
Expand the prefault memory selftest to add a regression test for a KVM bug where KVM's retry logic would result in (breakable) deadlock due to the memslot deletion waiting on prefaulting to release SRCU, and prefaulting waiting on the memslot to fully disappear (KVM uses a two-step process to delete memslots, and KVM x86 retries page faults if a to-be-deleted, a.k.a. INVALID, memslot is encountered). To exercise concurrent memslot remove, spawn a second thread to initiate memslot removal at roughly the same time as prefaulting. Test memslot removal for all testcases, i.e. don't limit concurrent removal to only the success case. There are essentially three prefault scenarios (so far) that are of interest: 1. Success 2. ENOENT due to no memslot 3. EAGAIN due to INVALID memslot For all intents and purposes, #1 and #2 are mutually exclusive, or rather, easier to test via separate testcases since writing to non-existent memory is trivial. But for #3, making it mutually exclusive with #1 _or_ #2 is actually more complex than testing memslot removal for all scenarios. The only requirement to let memslot removal coexist with other scenarios is a way to guarantee a stable result, e.g. that the "no memslot" test observes ENOENT, not EAGAIN, for the final checks. So, rather than make memslot removal mutually exclusive with the ENOENT scenario, simply restore the memslot and retry prefaulting. For the "no memslot" case, KVM_PRE_FAULT_MEMORY should be idempotent, i.e. should always fail with ENOENT regardless of how many times userspace attempts prefaulting. Pass in both the base GPA and the offset (instead of the "full" GPA) so that the worker can recreate the memslot. Signed-off-by: Yan Zhao <[email protected]> Co-developed-by: Sean Christopherson <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
kdave
pushed a commit
that referenced
this pull request
Oct 27, 2025
The original code causes a circular locking dependency found by lockdep. ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 Tainted: G S U ------------------------------------------------------ xe_fault_inject/5091 is trying to acquire lock: ffff888156815688 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}, at: __flush_work+0x25d/0x660 but task is already holding lock: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&devcd->mutex){+.+.}-{3:3}: mutex_lock_nested+0x4e/0xc0 devcd_data_write+0x27/0x90 sysfs_kf_bin_write+0x80/0xf0 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (kn->active#236){++++}-{0:0}: kernfs_drain+0x1e2/0x200 __kernfs_remove+0xae/0x400 kernfs_remove_by_name_ns+0x5d/0xc0 remove_files+0x54/0x70 sysfs_remove_group+0x3d/0xa0 sysfs_remove_groups+0x2e/0x60 device_remove_attrs+0xc7/0x100 device_del+0x15d/0x3b0 devcd_del+0x19/0x30 process_one_work+0x22b/0x6f0 worker_thread+0x1e8/0x3d0 kthread+0x11c/0x250 ret_from_fork+0x26c/0x2e0 ret_from_fork_asm+0x1a/0x30 -> #0 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}: __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 __flush_work+0x27a/0x660 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: (work_completion)(&(&devcd->del_wk)->work) --> kn->active#236 --> &devcd->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&devcd->mutex); lock(kn->active#236); lock(&devcd->mutex); lock((work_completion)(&(&devcd->del_wk)->work)); *** DEADLOCK *** 5 locks held by xe_fault_inject/5091: #0: ffff8881129f9488 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x72/0xf0 #1: ffff88810c755078 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x123/0x220 #2: ffff8881054811a0 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x55/0x280 #3: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 #4: ffffffff8359e020 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x72/0x660 stack backtrace: CPU: 14 UID: 0 PID: 5091 Comm: xe_fault_inject Tainted: G S U 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 PREEMPT_{RT,(lazy)} Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER Hardware name: Micro-Star International Co., Ltd. MS-7D25/PRO Z690-A DDR4(MS-7D25), BIOS 1.10 12/13/2021 Call Trace: <TASK> dump_stack_lvl+0x91/0xf0 dump_stack+0x10/0x20 print_circular_bug+0x285/0x360 check_noncircular+0x135/0x150 ? register_lock_class+0x48/0x4a0 __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 ? __flush_work+0x25d/0x660 ? mark_held_locks+0x46/0x90 ? __flush_work+0x25d/0x660 __flush_work+0x27a/0x660 ? __flush_work+0x25d/0x660 ? trace_hardirqs_on+0x1e/0xd0 ? __pfx_wq_barrier_func+0x10/0x10 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 ? bus_find_device+0xa8/0xe0 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 ? __f_unlock_pos+0x15/0x20 ? __x64_sys_getdents64+0x9b/0x130 ? __pfx_filldir64+0x10/0x10 ? do_syscall_64+0x1a2/0xb60 ? clear_bhb_loop+0x30/0x80 ? clear_bhb_loop+0x30/0x80 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x76e292edd574 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 RSP: 002b:00007fffe247a828 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000076e292edd574 RDX: 000000000000000c RSI: 00006267f6306063 RDI: 000000000000000b RBP: 000000000000000c R08: 000076e292fc4b20 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00006267f6306063 R13: 000000000000000b R14: 00006267e6859c00 R15: 000076e29322a000 </TASK> xe 0000:03:00.0: [drm] Xe device coredump has been deleted. Fixes: 01daccf ("devcoredump : Serialize devcd_del work") Cc: Mukesh Ojha <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Johannes Berg <[email protected]> Cc: Rafael J. Wysocki <[email protected]> Cc: Danilo Krummrich <[email protected]> Cc: [email protected] Cc: [email protected] # v6.1+ Signed-off-by: Maarten Lankhorst <[email protected]> Cc: Matthew Brost <[email protected]> Acked-by: Mukesh Ojha <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Please consider these fixes, in the area of handling devices and sysfs. Mainly they are bug fixes and framework changes. And towards the end of this patch set, I have two patches which are introducing two new features, device delete by devid and sysfs attributes for btrfs pool. These patches were sent to mailing list before.
Kindly note few of the subject are changed for good and to backtrack the old subject are maintained in the changelog. Also the review comment changes that some of the patches went through are also in the changelog, which probably should be deleted when merged.
Thanks, Anand