diff options
| author | Nicolas Pitre <nicolas.pitre@linaro.org> | 2018-10-30 13:26:15 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-13 11:17:03 -0800 |
| commit | aa52629c60b1c0a0957e3a679d169b0b85367e98 (patch) | |
| tree | ad935613e4cbd67afeaab97951b835b99df6cb4e /fs/cramfs | |
| parent | 245af7ee61ef0a399521a48babe12a32fa36d336 (diff) | |
Cramfs: fix abad comparison when wrap-arounds occur
commit 672ca9dd13f1aca0c17516f76fc5b0e8344b3e46 upstream.
It is possible for corrupted filesystem images to produce very large
block offsets that may wrap when a length is added, and wrongly pass
the buffer size test.
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/cramfs')
| -rw-r--r-- | fs/cramfs/inode.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c index 7919967488cb..011c6f53dcda 100644 --- a/fs/cramfs/inode.c +++ b/fs/cramfs/inode.c @@ -186,7 +186,8 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i continue; blk_offset = (blocknr - buffer_blocknr[i]) << PAGE_SHIFT; blk_offset += offset; - if (blk_offset + len > BUFFER_SIZE) + if (blk_offset > BUFFER_SIZE || + blk_offset + len > BUFFER_SIZE) continue; return read_buffers[i] + blk_offset; } |