{"id":"CVE-2025-21672","state":"PUBLISHED","title":"afs: Fix merge preference rule failure condition","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nafs: Fix merge preference rule failure condition\n\nsyzbot reported a lock held when returning to userspace[1].  This is\nbecause if argc is less than 0 and the function returns directly, the held\ninode lock is not released.\n\nFix this by store the error in ret and jump to done to clean up instead of\nreturning directly.\n\n[dh: Modified Lizhi Xu's original patch to make it honour the error code\nfrom afs_split_string()]\n\n[1]\nWARNING: lock held when returning to user space!\n6.13.0-rc3-syzkaller-00209-g499551201b5f #0 Not tainted\n------------------------------------------------\nsyz-executor133/5823 is leaving the kernel with locks still held!\n1 lock held by syz-executor133/5823:\n #0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]\n #0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: afs_proc_addr_prefs_write+0x2bb/0x14e0 fs/afs/addr_prefs.c:388","publishedAt":"2025-01-31T11:25:35.246Z","updatedAt":"2026-05-11T21:04:12.853Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f94f70d39cc2d54079ebae934862198516315db2","status":"affected","lessThan":"22be1d90a6211c88dd093b25d1f3aa974d0d9f9d","versionType":"git"},{"version":"f94f70d39cc2d54079ebae934862198516315db2","status":"affected","lessThan":"17a4fde81d3a7478d97d15304a6d61094a10c2e3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/afs/addr_prefs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.8","versionType":"semver"},{"version":"6.12.11","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/afs/addr_prefs.c"]}],"references":["https://git.kernel.org/stable/c/22be1d90a6211c88dd093b25d1f3aa974d0d9f9d","https://git.kernel.org/stable/c/17a4fde81d3a7478d97d15304a6d61094a10c2e3"],"weaknesses":["CWE-667"],"ingestedAt":"2026-10-29T20:08:39.238Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/21xxx/CVE-2025-21672.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-21672","state":"PUBLISHED","datePublished":"2025-01-31T11:25:35.246Z","dateUpdated":"2026-05-11T21:04:12.853Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-12-29T08:45:45.736Z"},"containers":{"cna":{"title":"afs: Fix merge preference rule failure condition","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nafs: Fix merge preference rule failure condition\n\nsyzbot reported a lock held when returning to userspace[1].  This is\nbecause if argc is less than 0 and the function returns directly, the held\ninode lock is not released.\n\nFix this by store the error in ret and jump to done to clean up instead of\nreturning directly.\n\n[dh: Modified Lizhi Xu's original patch to make it honour the error code\nfrom afs_split_string()]\n\n[1]\nWARNING: lock held when returning to user space!\n6.13.0-rc3-syzkaller-00209-g499551201b5f #0 Not tainted\n------------------------------------------------\nsyz-executor133/5823 is leaving the kernel with locks still held!\n1 lock held by syz-executor133/5823:\n #0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]\n #0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: afs_proc_addr_prefs_write+0x2bb/0x14e0 fs/afs/addr_prefs.c:388"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f94f70d39cc2d54079ebae934862198516315db2","status":"affected","lessThan":"22be1d90a6211c88dd093b25d1f3aa974d0d9f9d","versionType":"git"},{"version":"f94f70d39cc2d54079ebae934862198516315db2","status":"affected","lessThan":"17a4fde81d3a7478d97d15304a6d61094a10c2e3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/afs/addr_prefs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.8","versionType":"semver"},{"version":"6.12.11","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/afs/addr_prefs.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/22be1d90a6211c88dd093b25d1f3aa974d0d9f9d"},{"url":"https://git.kernel.org/stable/c/17a4fde81d3a7478d97d15304a6d61094a10c2e3"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:04:12.853Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.12.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.13"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2025-21672","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:52:11.531644Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-667","lang":"en","type":"CWE","description":"CWE-667 Improper Locking"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:57:12.173Z"}}]}}}