Description
In the Linux kernel, the following vulnerability has been resolved: ceph: fix crash after fscrypt_encrypt_pagecache_blocks() error The function move_dirty_folio_in_page_array() was created by commit ce80b76dd327 ("ceph: introduce ceph_process_folio_batch() method") by moving code from ceph_writepages_start() to this function. This new function is supposed to return an error code which is checked by the caller (now ceph_process_folio_batch()), and on error, the caller invokes redirty_page_for_writepage() and then breaks from the loop. However, the refactoring commit has gone wrong, and it by accident, it always returns 0 (= success) because it first NULLs the pointer and then returns PTR_ERR(NULL) which is always 0. This means errors are silently ignored, leaving NULL entries in the page array, which may later crash the kernel. The simple solution is to call PTR_ERR() before clearing the pointer.
Product status
ce80b76dd32764cc914975777e058d4fae4f0ea0 (git) before dd1616ecbea920d228c56729461ed223cc501425
ce80b76dd32764cc914975777e058d4fae4f0ea0 (git) before 249e0a47cdb46bb9eae65511c569044bd8698d7d
6.15
Any version before 6.15
6.16.8 (semver)
6.17 (original_commit_for_fix)
References
git.kernel.org/...c/dd1616ecbea920d228c56729461ed223cc501425
git.kernel.org/...c/249e0a47cdb46bb9eae65511c569044bd8698d7d
