Description
In the Linux kernel, the following vulnerability has been resolved: virtiofs: fix UAF on submount umount iput() called from fuse_release_end() can Oops if the super block has already been destroyed. Normally this is prevented by waiting for num_waiting to go down to zero before commencing with super block shutdown. This only works, however, for the last submount instance, as the wait counter is per connection, not per superblock. Revert to using synchronous release requests for the auto_submounts case, which is virtiofs only at this time.
Affected products
linux: linux kernel
References9
- git.kernel.org/stable/c/06b41351779e9289e8785694ade9042ae85e41ea Patch
- git.kernel.org/stable/c/0b809199ff87c44487e516a725dd4be2185712ce Patch
- git.kernel.org/stable/c/1cc0e3a0c6499aaaa2f21a4fcbba388486afb25e Patch
- git.kernel.org/stable/c/2181a09ba980f142650fb053666350ead4471cfe Patch
- git.kernel.org/stable/c/2abfd3ffbd9452f72535d96ff3982b3ab1f8f2f9 Patch
- git.kernel.org/stable/c/39a2b95e008665c14f84e50ed411d898df7cd11b Patch
- git.kernel.org/stable/c/607a1d4c42f649e6197567c0448fd9ebb316cd42 Patch
- git.kernel.org/stable/c/97c4691653d145dcc699eca5d3aba3219a520f1f Patch
- git.kernel.org/stable/c/e09412a714bcd49375198427bb4aa005037a9d6f Patch
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 3 · as of 14 November 2026
- CWE
- CWE-416
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