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| author | Wenjie Qi <qwjhust@gmail.com> | 2026-05-26 13:35:57 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-07-04 13:45:05 +0200 |
| commit | 2e12381d4495dc8b0ff042c6856022b2e359835c (patch) | |
| tree | 8fb2e9ac0ccff9bece344e04ffc285a3c4922fa7 | |
| parent | 0cc21c1ffe15b4156b0bf744f32fd1faef0b7c73 (diff) | |
| download | linux-stable-2e12381d4495dc8b0ff042c6856022b2e359835c.tar.gz linux-stable-2e12381d4495dc8b0ff042c6856022b2e359835c.zip | |
f2fs: validate orphan inode entry count
commit 846c499a65816d13f1186e3090e825e8bb8bcb8b upstream.
f2fs_recover_orphan_inodes() trusts the orphan block entry_count when
replaying orphan inodes from the checkpoint pack. A corrupted entry_count
larger than F2FS_ORPHANS_PER_BLOCK makes the recovery loop read past the
ino[] array and interpret footer or following data as inode numbers.
On a crafted image, mounting an unpatched kernel can drive orphan recovery
into f2fs_bug_on() and panic the kernel. Validate entry_count before
consuming entries so corrupted checkpoint data fails the mount with
-EFSCORRUPTED and requests fsck instead.
Set ERROR_INCONSISTENT_ORPHAN as well, so the corruption reason can be
recorded in the superblock s_errors[] field. This gives fsck a persistent
hint even though mount-time orphan recovery failure may leave no chance to
persist SBI_NEED_FSCK through a checkpoint.
Cc: stable@kernel.org
Fixes: 127e670abfa7 ("f2fs: add checkpoint operations")
Signed-off-by: Wenjie Qi <qiwenjie@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/f2fs/checkpoint.c | 14 | ||||
| -rw-r--r-- | include/linux/f2fs_fs.h | 1 |
2 files changed, 14 insertions, 1 deletions
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index c00a6b6ebcbd..064f5b537423 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -943,6 +943,7 @@ int f2fs_recover_orphan_inodes(struct f2fs_sb_info *sbi) for (i = 0; i < orphan_blocks; i++) { struct folio *folio; struct f2fs_orphan_block *orphan_blk; + unsigned int entry_count; folio = f2fs_get_meta_folio(sbi, start_blk + i); if (IS_ERR(folio)) { @@ -951,7 +952,18 @@ int f2fs_recover_orphan_inodes(struct f2fs_sb_info *sbi) } orphan_blk = folio_address(folio); - for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) { + entry_count = le32_to_cpu(orphan_blk->entry_count); + if (entry_count > F2FS_ORPHANS_PER_BLOCK) { + f2fs_err(sbi, "invalid orphan inode entry count %u", + entry_count); + set_sbi_flag(sbi, SBI_NEED_FSCK); + f2fs_handle_error(sbi, ERROR_INCONSISTENT_ORPHAN); + err = -EFSCORRUPTED; + f2fs_folio_put(folio, true); + goto out; + } + + for (j = 0; j < entry_count; j++) { nid_t ino = le32_to_cpu(orphan_blk->ino[j]); err = recover_orphan_inode(sbi, ino); diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h index 829a59399dac..bb2b6cd5d507 100644 --- a/include/linux/f2fs_fs.h +++ b/include/linux/f2fs_fs.h @@ -107,6 +107,7 @@ enum f2fs_error { ERROR_CORRUPTED_XATTR, ERROR_INVALID_NODE_REFERENCE, ERROR_INCONSISTENT_NAT, + ERROR_INCONSISTENT_ORPHAN, ERROR_MAX, }; |