diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2012-03-11 23:30:16 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-04-02 09:53:04 -0700 |
| commit | ac35405d20c0bd438cea6e9dddd84335370c739e (patch) | |
| tree | 5985f5c874dd90f87bc67d5370d6ec349ffb410e /fs/ext4/extents.c | |
| parent | 3b9dbd4b410c4b2dc27c71fab78e4dff9b29e14c (diff) | |
| download | linux-stable-ac35405d20c0bd438cea6e9dddd84335370c739e.tar.gz linux-stable-ac35405d20c0bd438cea6e9dddd84335370c739e.tar.bz2 linux-stable-ac35405d20c0bd438cea6e9dddd84335370c739e.zip | |
ext4: check for zero length extent
commit 31d4f3a2f3c73f279ff96a7135d7202ef6833f12 upstream.
Explicitly test for an extent whose length is zero, and flag that as a
corrupted extent.
This avoids a kernel BUG_ON assertion failure.
Tested: Without this patch, the file system image found in
tests/f_ext_zero_len/image.gz in the latest e2fsprogs sources causes a
kernel panic. With this patch, an ext4 file system error is noted
instead, and the file system is marked as being corrupted.
https://bugzilla.kernel.org/show_bug.cgi?id=42859
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ext4/extents.c')
| -rw-r--r-- | fs/ext4/extents.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 607b1557d292..75070365f479 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -301,6 +301,8 @@ static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext) ext4_fsblk_t block = ext4_ext_pblock(ext); int len = ext4_ext_get_actual_len(ext); + if (len == 0) + return 0; return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len); } |