CVSS 8.8 · High EPSS 0,43%
Kerentanan Use After Free pada linux kernel. Skor CVSS 3.1 8.8 (High) menurut CNA.
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free of a deferred file_lock on double SMB2_CANCEL A deferred byte-range lock (an SMB2_LOCK that blocks) registers an async work on conn->async_requests via setup_async_work(), with cancel_fn = smb2_remove_blocked_lock and cancel_argv[0] pointing at the struct file_lock. When the request is cancelled, the worker frees the file_lock with locks_free_lock() and takes the cancelled early-exit, which "goto out"s and never reaches release_async_work() -- the only site that unlinks the work from conn->async_requests and clears cancel_fn/cancel_argv. The work therefore stays matchable on async_requests with a live cancel_fn pointing at the freed file_lock, until connection teardown finally runs release_async_work(). smb2_cancel() fires cancel_fn unconditionally with no state guard, so a second SMB2_CANCEL for the same AsyncId, arriving in that window, re-runs smb2_remove_blocked_lock() on the freed file_lock -- a slab use-after-free: BUG: KASAN: slab-use-after-free in __locks_delete_block __locks_delete_block locks_delete_block ksmbd_vfs_posix_lock_unblock smb2_remove_blocked_lock smb2_cancel <- 2nd SMB2_CANCEL fires cancel_fn handle_ksmbd_work Allocated by ...: locks_alloc_lock <- smb2_lock Freed by ...: locks_free_lock <- smb2_lock (cancelled branch) ... cache file_lock_cache of size 192 Reproduced on mainline with KASAN by an authenticated SMB client. Skip a work whose state is already KSMBD_WORK_CANCELLED so its cancel callback cannot be fired a second time.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
· uraikan di kalkulator | Vendor | Produk | Versi terdampak |
|---|---|---|
| linux | linux kernel | Versi 5.15 hingga sebelum 6.1.176 |
| linux | linux kernel | Versi 6.2 hingga sebelum 6.6.143 |
| linux | linux kernel | Versi 6.7 hingga sebelum 6.12.94 |
| linux | linux kernel | Versi 6.13 hingga sebelum 6.18.36 |
| linux | linux kernel | Versi 6.19 hingga sebelum 7.0.13 |
| linux | linux kernel | Versi 7.1 rc1 |
| linux | linux kernel | Versi 7.1 rc2 |
| linux | linux kernel | Versi 7.1 rc3 |
| linux | linux kernel | Versi 7.1 rc4 |
| linux | linux kernel | Versi 7.1 rc5 |
| linux | linux kernel | Versi 7.1 rc6 |