CVE-2026-31647

Summary

In the Linux kernel, the following vulnerability has been resolved:

idpf: fix PREEMPT_RT raw/bh spinlock nesting for async VC handling

Switch from using the completion's raw spinlock to a local lock in the idpf_vc_xn struct. The conversion is safe because complete/_all() are called outside the lock and there is no reason to share the completion lock in the current logic. This avoids invalid wait context reported by the kernel due to the async handler taking BH spinlock:

[ 805.726977] ============================= [ 805.726991] [ BUG: Invalid wait context ] [ 805.727006] 7.0.0-rc2-net-devq-031026+ #28 Tainted: G S OE [ 805.727026] —————————– [ 805.727038] kworker/u261:0/572 is trying to lock: [ 805.727051] ff190da6a8dbb6a0 (&vport_config->mac_filter_list_lock){+…}-{3:3}, at: idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727099] other info that might help us debug this: [ 805.727111] context-{5:5} [ 805.727119] 3 locks held by kworker/u261:0/572: [ 805.727132] #0: ff190da6db3e6148 ((wq_completion)idpf-0000:83:00.0-mbx){+.+.}-{0:0}, at: process_one_work+0x4b5/0x730 [ 805.727163] #1: ff3c6f0a6131fe50 ((work_completion)(&(&adapter->mbx_task)->work)){+.+.}-{0:0}, at: process_one_work+0x1e5/0x730 [ 805.727191] #2: ff190da765190020 (&x->wait#34){+.+.}-{2:2}, at: idpf_recv_mb_msg+0xc8/0x710 [idpf] [ 805.727218] stack backtrace: … [ 805.727238] Workqueue: idpf-0000:83:00.0-mbx idpf_mbx_task [idpf] [ 805.727247] Call Trace: [ 805.727249] <TASK> [ 805.727251] dump_stack_lvl+0x77/0xb0 [ 805.727259] __lock_acquire+0xb3b/0x2290 [ 805.727268] ? __irq_work_queue_local+0x59/0x130 [ 805.727275] lock_acquire+0xc6/0x2f0 [ 805.727277] ? idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727284] ? _printk+0x5b/0x80 [ 805.727290] _raw_spin_lock_bh+0x38/0x50 [ 805.727298] ? idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727303] idpf_mac_filter_async_handler+0xe9/0x260 [idpf] [ 805.727310] idpf_recv_mb_msg+0x1c8/0x710 [idpf] [ 805.727317] process_one_work+0x226/0x730 [ 805.727322] worker_thread+0x19e/0x340 [ 805.727325] ? __pfx_worker_thread+0x10/0x10 [ 805.727328] kthread+0xf4/0x130 [ 805.727333] ? __pfx_kthread+0x10/0x10 [ 805.727336] ret_from_fork+0x32c/0x410 [ 805.727345] ? __pfx_kthread+0x10/0x10 [ 805.727347] ret_from_fork_asm+0x1a/0x30 [ 805.727354] </TASK>

Affected Software

VendorProductVersion RangeStatus
LinuxLinux34c21fa894a1af6166f4284c81d1dc21efed8f38 < b448529f2f2921c6fe82fd4e985cc7c05cbf02a3affected
LinuxLinux34c21fa894a1af6166f4284c81d1dc21efed8f38 < e02c974fc331f04b5ba2007d4bc6862df8a43148affected
LinuxLinux34c21fa894a1af6166f4284c81d1dc21efed8f38 < 3bb632c6b6d8154e9019beda4a43a4b518ee3e8aaffected
LinuxLinux34c21fa894a1af6166f4284c81d1dc21efed8f38 < 591478118293c1bd628de330a99eb1eb2ef8d76baffected
LinuxLinux6.9affected
LinuxLinux0 < 6.9unaffected
LinuxLinux6.12.83 <= 6.12.*unaffected
LinuxLinux6.18.23 <= 6.18.*unaffected
LinuxLinux6.19.13 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References