Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix invalid pointer dereference in __btrfs_run_delayed_refs() In the beginning of the loop, we try to obtain a locked delayed ref head, if 'locked_ref' is currently NULL, by calling btrfs_select_ref_head(), which can return an error pointer. If the error pointer is -EAGAIN we do a continue and go back to the beginning of the loop, which will not try again to call btrfs_select_ref_head() since 'locked_ref' is no longer NULL but it's ERR_PTR(-EAGAIN), and then we do: spin_lock(&locked_ref->lock); against a ERR_PTR(-EAGAIN) value, generating an invalid pointer dereference. Fix this by ensuring that 'locked_ref' is set to NULL when btrfs_select_ref_head() returns ERR_PTR(-EAGAIN) and incrementing 'count' as well, to prevent infinite looping. We do this by doing a goto to the bottom of the loop that already sets 'locked_ref' to NULL and does a cond_resched(), with an increment to 'count' right before the goto. These measures were in place before the refactoring in commit 0110a4c43451 ("btrfs: refactor __btrfs_run_delayed_refs loop") but were unintentionally lost afterwards.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before c372ca227e16bace86f1df1fa4ae6849e2fcfa28; affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before a71143590ce9764dbcb47617647592ff8b4d48bc; affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before 65770111a2d47c2b15e20b2ba92bb12198f289d4; affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before 015dc4a1e0c2cba551d4620eba13d26d5081dc34; affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before ba9fa2ff5981589bb49094d3358c339b37c47f53; affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before 3b15d02be05e74321adb1e0ae0cb4ccfba7c6cb1; affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before 9faa6b69ad73f03c7bde53e07d75a28822dc9a1a; affected 0110a4c43451533de1ea1bbdc57b5d452f9d8b25 before 486f8298b6188ff11ef1f4be7f1d5d2e4d1b1fae |
| Linux / Linux | affected 4.20; unaffected 0 before 4.20; unaffected 5.10.261 through 5.10.*; unaffected 5.15.212 through 5.15.*; unaffected 6.1.178 through 6.1.*; unaffected 6.6.145 through 6.6.*; unaffected 6.12.97 through 6.12.*; unaffected 6.18.40 through 6.18.*; unaffected 7.1.5 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
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
ADP enrichment
No English description supplied.
No references supplied.