{"id":"CVE-2026-74321","revision":"2cba8a32a4574ba2abe08f8b4cd54cb4","records":[{"revision":"2cba8a32a4574ba2abe08f8b4cd54cb4","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-74321","aliases":[],"title":"btrfs: fix invalid pointer dereference in __btrfs_run_delayed_refs()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix invalid pointer dereference in __btrfs_run_delayed_refs()\n\nIn the beginning of the loop, we try to obtain a locked delayed ref head,\nif 'locked_ref' is currently NULL, by calling btrfs_select_ref_head(),\nwhich can return an error pointer. If the error pointer is -EAGAIN we do\na continue and go back to the beginning of the loop, which will not try\nagain to call btrfs_select_ref_head() since 'locked_ref' is no longer\nNULL but it's ERR_PTR(-EAGAIN), and then we do:\n\n   spin_lock(&locked_ref->lock);\n\nagainst a ERR_PTR(-EAGAIN) value, generating an invalid pointer\ndereference.\n\nFix this by ensuring that 'locked_ref' is set to NULL when\nbtrfs_select_ref_head() returns ERR_PTR(-EAGAIN) and incrementing 'count'\nas well, to prevent infinite looping. We do this by doing a goto to the\nbottom of the loop that already sets 'locked_ref' to NULL and does a\ncond_resched(), with an increment to 'count' right before the goto.\nThese measures were in place before the refactoring in commit 0110a4c43451\n(\"btrfs: refactor __btrfs_run_delayed_refs loop\") but were unintentionally\nlost afterwards.","state":0,"publishedAt":"2026-08-15T05:58:17.485+00:00","modifiedAt":"2026-10-16T18:55:32.917+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/btrfs/extent-tree.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"c372ca227e16bace86f1df1fa4ae6849e2fcfa28\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"a71143590ce9764dbcb47617647592ff8b4d48bc\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"65770111a2d47c2b15e20b2ba92bb12198f289d4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"015dc4a1e0c2cba551d4620eba13d26d5081dc34\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"ba9fa2ff5981589bb49094d3358c339b37c47f53\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"3b15d02be05e74321adb1e0ae0cb4ccfba7c6cb1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"9faa6b69ad73f03c7bde53e07d75a28822dc9a1a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"0110a4c43451533de1ea1bbdc57b5d452f9d8b25\",\n                            \"lessThan\": \"486f8298b6188ff11ef1f4be7f1d5d2e4d1b1fae\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/btrfs/extent-tree.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.20\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.20\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.261\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.212\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.178\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.145\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.97\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.40\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.5\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/c372ca227e16bace86f1df1fa4ae6849e2fcfa28","https://git.kernel.org/stable/c/a71143590ce9764dbcb47617647592ff8b4d48bc","https://git.kernel.org/stable/c/65770111a2d47c2b15e20b2ba92bb12198f289d4","https://git.kernel.org/stable/c/015dc4a1e0c2cba551d4620eba13d26d5081dc34","https://git.kernel.org/stable/c/ba9fa2ff5981589bb49094d3358c339b37c47f53","https://git.kernel.org/stable/c/3b15d02be05e74321adb1e0ae0cb4ccfba7c6cb1","https://git.kernel.org/stable/c/9faa6b69ad73f03c7bde53e07d75a28822dc9a1a","https://git.kernel.org/stable/c/486f8298b6188ff11ef1f4be7f1d5d2e4d1b1fae"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74321","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-74321","identifiers":["CVE-2026-74321"]},"retained":false,"historicalAffected":[]}],"coverage":[]}