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 10:32:20 -0700 |
| commit | 786be162a8f2e92d72fa3c4e66e6f7fe497a0f9d (patch) | |
| tree | 59984f13df8dbfcd03fe1ebda36d860daf7797c9 /fs | |
| parent | 2cb2d68b88999a013ab781ebd9a1e1382b150fc6 (diff) | |
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')
| -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 74f23c292e1b..4394a757aa4c 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -300,6 +300,8 @@ 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); } |