CVEvulnerability
CVE-2026-74728
- Status
- Received
- Published
- 2026-08-22
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
xfs: handle NULL b_addr in xfs_buf_free
When xfs_buf_alloc_backing_mem() fails, xfs_buf_free() is called with
bp->b_addr still NULL. The code falls through to the folio_put path
which calls virt_to_folio(NULL), dereferencing an invalid address and
causing a kernel crash.
Call Trace:
xfs_buf_free+0x25f/0x510
xfs_buf_alloc+0xc98/0x19b0
xfs_buf_find_insert+0x55/0x14d0
xfs_buf_get_map+0x122b/0x17c0
xfbtree_init_leaf_block+0x11c/0x4a0
xfbtree_init+0x1bb/0x460
xrep_rmap_setup_scan+0x100/0x1f0
xrep_rmapbt+0x41/0xc0
Fix this by skipping folio_put() when bp->b_addr is NULL.
References
- https://git.kernel.org/stable/c/3aa0c1d23ee1b9d9b340fb2f4736536e1408d706 git.kernel.org
- https://git.kernel.org/stable/c/444ff50ece93060131ad84fbd3f378723d8ac243 git.kernel.org
- https://git.kernel.org/stable/c/ccf6738adcafa5ddbddc4e71b45d8a51b86643c7 git.kernel.org
- https://git.kernel.org/stable/c/d852729c5f4f830fbe7413df032e29459b3daf83 git.kernel.org