AZL-90620
See a problem?- Import Source
- https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-90620.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/AZL-90620
- Upstream
- Published
- 2026-06-25T09:16:33Z
- Modified
- 2026-08-28T17:47:53Z
- Summary
- CVE-2026-53163 affecting package kernel for versions less than 6.6.144.1-1
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
locking/rtmutex: Skip remove_waiter() when waiter is not enqueued
syzbot triggered the following splat in remove_waiter() via FUTEX_CMP_REQUEUE_PI:
KASAN: null-ptr-deref in range [0x0000000000000a88-0x0000000000000a8f] class_raw_spinlock_constructor remove_waiter+0x159/0x1200 kernel/locking/rtmutex.c:1561 rt_mutex_start_proxy_lock+0x103/0x120 futex_requeue+0x10e4/0x20d0 __x64_sys_futex+0x34f/0x4d0
task_blocks_on_rt_mutex() does not arm the waiter upon deadlock detection, leaving waiter->task nil, where 3bfdc63936dd ("rtmutex: Use waiter::task instead of current in remove_waiter()") made this fatal.
Furthermore, rt_mutex_start_proxy_lock() should not be calling into remove_waiter() upon a successfully grabbing the rtmutex. 1a1fb985f2e2 ("futex: Handle early deadlock return correctly"), moved the remove_waiter() out of __rt_mutex_start_proxy_lock() (where 'ret' was only ever 0 or < 0) into the wrapper. Tighten this check to account for try_to_take_rt_mutex().
- References