diff options
| author | Eric Sandeen <sandeen@redhat.com> | 2007-10-16 23:27:15 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-17 08:42:53 -0700 |
| commit | f44ec6f3f89889a469773b1fd894f8fcc07c29cf (patch) | |
| tree | 3b58f7b094e61c02536c7414906d7e29190979de | |
| parent | d8ea6cf89991000ae458e34e36379814cf202555 (diff) | |
| download | lwn-f44ec6f3f89889a469773b1fd894f8fcc07c29cf.tar.gz lwn-f44ec6f3f89889a469773b1fd894f8fcc07c29cf.zip | |
limit minixfs printks on corrupted dir i_size
This attempts to address CVE-2006-6058
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-6058
first reported at http://projects.info-pull.com/mokb/MOKB-17-11-2006.html
Essentially a corrupted minix dir inode reporting a very large
i_size will loop for a very long time in minix_readdir, minix_find_entry,
etc, because on EIO they just move on to try the next page. This is
under the BKL, printk-storming as well. This can lock up the machine
for a very long time. Simply ratelimiting the printks gets things back
under control. Make the message a bit more informative while we're here.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: Bodo Eggert <7eggert@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/minix/itree_v1.c | 9 | ||||
| -rw-r--r-- | fs/minix/itree_v2.c | 9 |
2 files changed, 14 insertions, 4 deletions
diff --git a/fs/minix/itree_v1.c b/fs/minix/itree_v1.c index 1a5f3bf0bcec..82d6554b02fe 100644 --- a/fs/minix/itree_v1.c +++ b/fs/minix/itree_v1.c @@ -23,11 +23,16 @@ static inline block_t *i_data(struct inode *inode) static int block_to_path(struct inode * inode, long block, int offsets[DEPTH]) { int n = 0; + char b[BDEVNAME_SIZE]; if (block < 0) { - printk("minix_bmap: block<0\n"); + printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n", + block, bdevname(inode->i_sb->s_bdev, b)); } else if (block >= (minix_sb(inode->i_sb)->s_max_size/BLOCK_SIZE)) { - printk("minix_bmap: block>big\n"); + if (printk_ratelimit()) + printk("MINIX-fs: block_to_path: " + "block %ld too big on dev %s\n", + block, bdevname(inode->i_sb->s_bdev, b)); } else if (block < 7) { offsets[n++] = block; } else if ((block -= 7) < 512) { diff --git a/fs/minix/itree_v2.c b/fs/minix/itree_v2.c index ad8f0dec4ef4..f23010969369 100644 --- a/fs/minix/itree_v2.c +++ b/fs/minix/itree_v2.c @@ -23,12 +23,17 @@ static inline block_t *i_data(struct inode *inode) static int block_to_path(struct inode * inode, long block, int offsets[DEPTH]) { int n = 0; + char b[BDEVNAME_SIZE]; struct super_block *sb = inode->i_sb; if (block < 0) { - printk("minix_bmap: block<0\n"); + printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n", + block, bdevname(sb->s_bdev, b)); } else if (block >= (minix_sb(inode->i_sb)->s_max_size/sb->s_blocksize)) { - printk("minix_bmap: block>big\n"); + if (printk_ratelimit()) + printk("MINIX-fs: block_to_path: " + "block %ld too big on dev %s\n", + block, bdevname(sb->s_bdev, b)); } else if (block < 7) { offsets[n++] = block; } else if ((block -= 7) < 256) { |