diff options
| author | Nicolas Pitre <nicolas.pitre@linaro.org> | 2018-10-30 20:26:15 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-22 09:32:45 +0300 |
| commit | 2b4fc4a191ca24878592e6e9904b83b02873aaaa (patch) | |
| tree | 9f381f5e0920a4149346d9ccc27bb568ef3bd927 /fs/cramfs | |
| parent | 2a30b6b06fcf3c075791aa46b837aeb8b9ba793e (diff) | |
| download | linux-2b4fc4a191ca24878592e6e9904b83b02873aaaa.tar.xz | |
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 355c522f3585..a6c9c2d66af1 100644 --- a/fs/cramfs/inode.c +++ b/fs/cramfs/inode.c @@ -185,7 +185,8 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i continue; blk_offset = (blocknr - buffer_blocknr[i]) << PAGE_CACHE_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; } |