CVE-2026-68149 (GCVE-0-2026-68149)
Vulnerability from cvelistv5
Published
2026-08-10 11:59
Modified
2026-10-19 20:58
Severity ?
8.4 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Summary
In the Linux kernel, the following vulnerability has been resolved: fs: preserve ACL_DONT_CACHE state in forget_cached_acl() The ACL_DONT_CACHE state is meant to be a constant state for the inode for filesystems that want to opt out of posix acl caching. Commit facd61053cff1 ("fuse: fixes after adapting to new posix acl api") used this facility to opt out of posix acl caching for fuse inodes with fuse server that does not negotiate FUSE_POSIX_ACL (fc->posix_acl). The commit also takes care to gate the forget_all_cached_acls() call in fuse_set_acl() on fc->posix_acl because there is no need for it, but there are other placed in fuse code which call forget_all_cached_acls() unconditional to fc->posix_acl and those cause the loss of the ACL_DONT_CACHE state. This is not only a functional bug. Properly timed, a get_acl() from this fuse filesystem can return a stale cached value, as was observed in tests, because set_acl() does not invalidate the unintentional acl cache. We could fix this in fuse, but it actually makes no sense for the vfs helper forget_cached_acl() to invalidate the ACL_DONT_CACHE state, so let it not do that to fix fuse and future users of ACL_DONT_CACHE.
References
Impacted products
Vendor Product Version
Linux Linux Version: facd61053cff100973921d4d45d47cf53c747ec6
Version: facd61053cff100973921d4d45d47cf53c747ec6
Version: facd61053cff100973921d4d45d47cf53c747ec6
Version: facd61053cff100973921d4d45d47cf53c747ec6
Version: facd61053cff100973921d4d45d47cf53c747ec6
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