diff options
| author | Kazuya Mio <k-mio@sx.jp.nec.com> | 2014-04-07 10:53:28 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-05-06 07:59:36 -0700 |
| commit | 549b3cf1c4393f2020e375dcbf891c2c811036b8 (patch) | |
| tree | 0ea8745344e8413fdd834b24c26a9989f13dcf2a | |
| parent | b4140e2b766bb20f0eb9d363be9072905977c5e0 (diff) | |
ext4: FIBMAP ioctl causes BUG_ON due to handle EXT_MAX_BLOCKS
commit 4adb6ab3e0fa71363a5ef229544b2d17de6600d7 upstream.
When we try to get 2^32-1 block of the file which has the extent
(ee_block=2^32-2, ee_len=1) with FIBMAP ioctl, it causes BUG_ON
in ext4_ext_put_gap_in_cache().
To avoid the problem, ext4_map_blocks() needs to check the file logical block
number. ext4_ext_put_gap_in_cache() called via ext4_map_blocks() cannot
handle 2^32-1 because the maximum file logical block number is 2^32-2.
Note that ext4_ind_map_blocks() returns -EIO when the block number is invalid.
So ext4_map_blocks() should also return the same errno.
Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/ext4/inode.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 24bfd7ff3049..b0d5860c0e50 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -515,6 +515,10 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, "logical block %lu\n", inode->i_ino, flags, map->m_len, (unsigned long) map->m_lblk); + /* We can handle the block number less than EXT_MAX_BLOCKS */ + if (unlikely(map->m_lblk >= EXT_MAX_BLOCKS)) + return -EIO; + /* Lookup extent status tree firstly */ if (ext4_es_lookup_extent(inode, map->m_lblk, &es)) { ext4_es_lru_add(inode); |