CVE-2024-47660
In the Linux kernel, the following vulnerability has been resolved: fsnotify: clear PARENT_WATCHED flags lazily In some setups directories can have many (usually negative) dentries.
Does this matter?
Lower severity and a low EPSS score (0.16%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: fsnotify: clear PARENT_WATCHED flags lazily In some setups directories can have many (usually negative) dentries. Hence __fsnotify_update_child_dentry_flags() function can take a significant amount of time. Since the bulk of this function happens under inode->i_lock this causes a significant contention on the lock when we remove the watch from the directory as the __fsnotify_update_child_dentry_flags() call from fsnotify_recalc_mask() races with __fsnotify_update_child_dentry_flags() calls from __fsnotify_parent() happening on children. This can lead upto softlockup reports reported by users. Fix the problem by calling fsnotify_update_children_dentry_flags() to set PARENT_WATCHED flags only when parent starts watching children. When parent stops watching children, clear false positive PARENT_WATCHED flags lazily in __fsnotify_parent() for each accessed child.
- CVSS 3.1
- 4.7 MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.16% probability · 5th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-362
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/172e422ffea20a89bfdc672741c1aad6fbb5044ePatch
- https://git.kernel.org/stable/c/3f3ef1d9f66b93913ce2171120d9226b55acd41dPatch
- https://git.kernel.org/stable/c/7ef1d2e240c32b1f337a37232d037b07e3919e1aPatch
- https://git.kernel.org/stable/c/d8c42405fc3507cc43ba7e4986a773c3fc633f6ePatch
- https://git.kernel.org/stable/c/f9a48bc3dd9099935751458a5bbbea4b7c28abc8Patch
- https://git.kernel.org/stable/c/fc1b1e135c3f72382f792e6c319fc088d5523ad5Patch
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
- https://cert-portal.siemens.com/productcert/html/ssa-355557.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.