Description
In the Linux kernel, the following vulnerability has been resolved: io_uring/tctx: work around xa_store() allocation error issue syzbot triggered the following WARN_ON: WARNING: CPU: 0 PID: 16 at io_uring/tctx.c:51 __io_uring_free+0xfa/0x140 io_uring/tctx.c:51 which is the WARN_ON_ONCE(!xa_empty(&tctx->xa)); sanity check in __io_uring_free() when a io_uring_task is going through its final put. The syzbot test case includes injecting memory allocation failures, and it very much looks like xa_store() can fail one of its memory allocations and end up with ->head being non-NULL even though no entries exist in the xarray. Until this issue gets sorted out, work around it by attempting to iterate entries in our xarray, and WARN_ON_ONCE() if one is found.
Affected products
linux: linux kernel
References7
- git.kernel.org/stable/c/42882b583095dcf747da6e3af1daeff40e27033e Patch
- git.kernel.org/stable/c/7eb75ce7527129d7f1fee6951566af409a37a1c4 Patch
- git.kernel.org/stable/c/94ad56f61b873ffeebcc620d451eacfbdf9d40f0 Patch
- git.kernel.org/stable/c/d5b2ddf1f90c7248eff9630b95895c8950f2f36d Patch
- git.kernel.org/stable/c/3a84fa784710990964c1e35df743851ab2863898
- git.kernel.org/stable/c/e05c070b401f6365c503e2b59f091331965c4fb9
- lists.debian.org/debian-lts-announce/2025/03/msg00001.html
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 15 · as of 6 November 2026
- CWE
- CWE-770
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