CVE-2026-53381

Summary

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 Software

VendorProductVersion RangeStatus
LinuxLinux548e1f2bac1d4df91a6138f26bb4ab00323fd948 < 607a1d4c42f649e6197567c0448fd9ebb316cd42affected
LinuxLinuxcfd1aa3e2b71f3327cb373c45a897c9028c62b35 < 1cc0e3a0c6499aaaa2f21a4fcbba388486afb25eaffected
LinuxLinux83b375c6efef69b1066ad2d79601221e7892745a < 0b809199ff87c44487e516a725dd4be2185712ceaffected
LinuxLinuxbfd17b6138df0122a95989457d8e18ce0b86165e < 2181a09ba980f142650fb053666350ead4471cfeaffected
LinuxLinuxb26923512dbe57ae4917bafd31396d22a9d1691a < 97c4691653d145dcc699eca5d3aba3219a520f1faffected
LinuxLinux26e5c67deb2e1f42a951f022fdf5b9f7eb747b01 < 2abfd3ffbd9452f72535d96ff3982b3ab1f8f2f9affected
LinuxLinux26e5c67deb2e1f42a951f022fdf5b9f7eb747b01 < 39a2b95e008665c14f84e50ed411d898df7cd11baffected
LinuxLinux26e5c67deb2e1f42a951f022fdf5b9f7eb747b01 < e09412a714bcd49375198427bb4aa005037a9d6faffected
LinuxLinux26e5c67deb2e1f42a951f022fdf5b9f7eb747b01 < 06b41351779e9289e8785694ade9042ae85e41eaaffected
LinuxLinuxf19a1390af448d9e193c08e28ea5f727bf3c3049affected
LinuxLinux5.10.246 < 5.10.260affected
LinuxLinux5.15.196 < 5.15.211affected
LinuxLinux6.1.158 < 6.1.177affected
LinuxLinux6.6.115 < 6.6.144affected
LinuxLinux6.12.54 < 6.12.95affected
LinuxLinux6.17.4 < 6.18affected
LinuxLinux6.18affected
LinuxLinux0 < 6.18unaffected
LinuxLinux5.10.260 <= 5.10.*unaffected
LinuxLinux5.15.211 <= 5.15.*unaffected
LinuxLinux6.1.177 <= 6.1.*unaffected
LinuxLinux6.6.144 <= 6.6.*unaffected
LinuxLinux6.12.95 <= 6.12.*unaffected
LinuxLinux6.18.37 <= 6.18.*unaffected
LinuxLinux7.0.14 <= 7.0.*unaffected
LinuxLinux7.1.2 <= 7.1.*unaffected
LinuxLinux7.2-rc1 <= *unaffected

Weaknesses

References