diff options
| author | Max Kellermann <max.kellermann@ionos.com> | 2025-08-28 13:15:52 +0200 |
|---|---|---|
| committer | Ilya Dryomov <idryomov@gmail.com> | 2025-09-09 12:57:03 +0200 |
| commit | 249e0a47cdb46bb9eae65511c569044bd8698d7d (patch) | |
| tree | 9521a366f6f967d684d40bac34556dd1b533bdf3 | |
| parent | cce7c15faaac79b532a07ed6ab8332280ad83762 (diff) | |
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.
Cc: stable@vger.kernel.org
Fixes: ce80b76dd327 ("ceph: introduce ceph_process_folio_batch() method")
Link: https://lore.kernel.org/ceph-devel/aK4v548CId5GIKG1@swift.blarg.de/
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
| -rw-r--r-- | fs/ceph/addr.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 8bc66b45dade..322ed268f14a 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -1264,7 +1264,9 @@ static inline int move_dirty_folio_in_page_array(struct address_space *mapping, 0, gfp_flags); if (IS_ERR(pages[index])) { - if (PTR_ERR(pages[index]) == -EINVAL) { + int err = PTR_ERR(pages[index]); + + if (err == -EINVAL) { pr_err_client(cl, "inode->i_blkbits=%hhu\n", inode->i_blkbits); } @@ -1273,7 +1275,7 @@ static inline int move_dirty_folio_in_page_array(struct address_space *mapping, BUG_ON(ceph_wbc->locked_pages == 0); pages[index] = NULL; - return PTR_ERR(pages[index]); + return err; } } else { pages[index] = &folio->page; |