Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix potential UAF of struct nilfs_sc_info in nilfs_segctor_thread() The finalization of nilfs_segctor_thread() can race with nilfs_segctor_kill_thread() which terminates that thread, potentially causing a use-after-free BUG as KASAN detected. At the end of nilfs_segctor_thread(), it assigns NULL to "sc_task" member of "struct nilfs_sc_info" to indicate the thread has finished, and then notifies nilfs_segctor_kill_thread() of this using waitqueue "sc_wait_task" on the struct nilfs_sc_info. However, here, immediately after the NULL assignment to "sc_task", it is possible that nilfs_segctor_kill_thread() will detect it and return to continue the deallocation, freeing the nilfs_sc_info structure before the thread does the notification. This fixes the issue by protecting the NULL assignment to "sc_task" and its notification, with spinlock "sc_state_lock" of the struct nilfs_sc_info. Since nilfs_segctor_kill_thread() does a final check to see if "sc_task" is NULL with "sc_state_lock" locked, this can eliminate the race.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before 034cce77d52ba013ce62b4f5258c29907eb1ada5; affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before 0dbf0e64b91ee8fcb278aea93eb06fc7d56ecbcc; affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before 613bf23c070d11c525268f2945aa594704a9b764; affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before f32297dba338dc06d62286dedb3cdbd5175b1719; affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before 92684e02654c91a61a0b0561433b710bcece19fe; affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before bae009a2f1b7c2011d2e92d8c84868d315c0b97e; affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before b4d80bd6370b81a1725b6b8f7894802c23a14e9f; affected 9ff05123e3bfbb1d2b68ba1d9bf1f7d1dffc1453 before 6be49d100c22ffea3287a4b19d7639d259888e33 |
| Linux / Linux | affected 2.6.30; unaffected 0 before 2.6.30; unaffected 4.14.313 through 4.14.*; unaffected 4.19.281 through 4.19.*; unaffected 5.4.241 through 5.4.*; unaffected 5.10.178 through 5.10.*; unaffected 5.15.107 through 5.15.*; unaffected 6.1.24 through 6.1.*; unaffected 6.2.11 through 6.2.*; unaffected 6.3 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/034cce77d52ba013ce62b4f5258c29907eb1ada5
- https://git.kernel.org/stable/c/0dbf0e64b91ee8fcb278aea93eb06fc7d56ecbcc
- https://git.kernel.org/stable/c/613bf23c070d11c525268f2945aa594704a9b764
- https://git.kernel.org/stable/c/f32297dba338dc06d62286dedb3cdbd5175b1719
- https://git.kernel.org/stable/c/92684e02654c91a61a0b0561433b710bcece19fe
- https://git.kernel.org/stable/c/bae009a2f1b7c2011d2e92d8c84868d315c0b97e
- https://git.kernel.org/stable/c/b4d80bd6370b81a1725b6b8f7894802c23a14e9f
- https://git.kernel.org/stable/c/6be49d100c22ffea3287a4b19d7639d259888e33