[PATCH] libext2fs: Add sanity checks to ext2fs_{block,inode}_alloc_stats

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



If ext2fs_inode_alloc_stats2() or ext2fs_block_alloc_stats() is passed
an insanely large inode or block number, it's possible for these
functions to overrun an array boundary and cause the calling program
to crash with a memory error.

Detect this case, and since these functions don't return an error
code, print a warning message, much like we do in ext2fs_warn_bitmap2().

Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx>
---
 lib/ext2fs/alloc_stats.c |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/lib/ext2fs/alloc_stats.c b/lib/ext2fs/alloc_stats.c
index 97661dc..d523b43 100644
--- a/lib/ext2fs/alloc_stats.c
+++ b/lib/ext2fs/alloc_stats.c
@@ -20,6 +20,13 @@ void ext2fs_inode_alloc_stats2(ext2_filsys fs, ext2_ino_t ino,
 {
 	int	group = ext2fs_group_of_ino(fs, ino);
 
+#ifndef OMIT_COM_ERR
+	if (ino > fs->super->s_inodes_count) {
+		com_err("ext2fs_inode_alloc_stats2", 0,
+			"Illegal inode number: %lu", ino);
+		return;
+	}
+#endif
 	if (inuse > 0)
 		ext2fs_mark_inode_bitmap(fs->inode_map, ino);
 	else
@@ -58,6 +65,13 @@ void ext2fs_block_alloc_stats(ext2_filsys fs, blk_t blk, int inuse)
 {
 	int	group = ext2fs_group_of_blk(fs, blk);
 
+#ifndef OMIT_COM_ERR
+	if (blk >= fs->super->s_blocks_count) {
+		com_err("ext2fs_block_alloc_stats2", 0,
+			"Illegal block number: %lu", blk);
+		return;
+	}
+#endif
 	if (inuse > 0)
 		ext2fs_mark_block_bitmap(fs->block_map, blk);
 	else
-- 
1.6.0.4.8.g36f27.dirty

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Reiser Filesystem Development]     [Ceph FS]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite National Park]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]     [Linux Media]

  Powered by Linux