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| author | Zhang Yi <yi.zhang@huawei.com> | 2021-09-08 15:08:48 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-12-29 14:28:37 +0300 |
| commit | f71ab21b1a281d7f0769c1ca608241c2659ae3f8 (patch) | |
| tree | 1da7eef0f5e857e1d78c5cf8de512f16ec5c6f3b /fs/ext4 | |
| parent | 02f825cf0255b9d9858acfe57c5ac29e2bc3eff8 (diff) | |
| download | linux-f71ab21b1a281d7f0769c1ca608241c2659ae3f8.tar.xz | |
ext4: check for out-of-order index extents in ext4_valid_extent_entries()
commit 8dd27fecede55e8a4e67eef2878040ecad0f0d33 upstream.
After commit 5946d089379a ("ext4: check for overlapping extents in
ext4_valid_extent_entries()"), we can check out the overlapping extent
entry in leaf extent blocks. But the out-of-order extent entry in index
extent blocks could also trigger bad things if the filesystem is
inconsistent. So this patch add a check to figure out the out-of-order
index extents and return error.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210908120850.4012324-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/extents.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index e7703b10830a..01f2b8df0869 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -370,6 +370,9 @@ static int ext4_valid_extent_entries(struct inode *inode, ext4_fsblk_t *pblk, int depth) { unsigned short entries; + ext4_lblk_t lblock = 0; + ext4_lblk_t prev = 0; + if (eh->eh_entries == 0) return 1; @@ -378,31 +381,35 @@ static int ext4_valid_extent_entries(struct inode *inode, if (depth == 0) { /* leaf entries */ struct ext4_extent *ext = EXT_FIRST_EXTENT(eh); - ext4_lblk_t lblock = 0; - ext4_lblk_t prev = 0; - int len = 0; while (entries) { if (!ext4_valid_extent(inode, ext)) return 0; /* Check for overlapping extents */ lblock = le32_to_cpu(ext->ee_block); - len = ext4_ext_get_actual_len(ext); if ((lblock <= prev) && prev) { *pblk = ext4_ext_pblock(ext); return 0; } + prev = lblock + ext4_ext_get_actual_len(ext) - 1; ext++; entries--; - prev = lblock + len - 1; } } else { struct ext4_extent_idx *ext_idx = EXT_FIRST_INDEX(eh); while (entries) { if (!ext4_valid_extent_idx(inode, ext_idx)) return 0; + + /* Check for overlapping index extents */ + lblock = le32_to_cpu(ext_idx->ei_block); + if ((lblock <= prev) && prev) { + *pblk = ext4_idx_pblock(ext_idx); + return 0; + } ext_idx++; entries--; + prev = lblock; } } return 1; |