From: Ryusuke Konishi Date: Fri, 27 Feb 2015 23:51:56 +0000 (-0800) Subject: nilfs2: fix potential memory overrun on inode X-Git-Tag: v3.2.69~147 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=db92697414a6e91bb5c467a02665e7bf91033fd5;p=pandora-kernel.git nilfs2: fix potential memory overrun on inode commit 957ed60b53b519064a54988c4e31e0087e47d091 upstream. Each inode of nilfs2 stores a root node of a b-tree, and it turned out to have a memory overrun issue: Each b-tree node of nilfs2 stores a set of key-value pairs and the number of them (in "bn_nchildren" member of nilfs_btree_node struct), as well as a few other "bn_*" members. Since the value of "bn_nchildren" is used for operations on the key-values within the b-tree node, it can cause memory access overrun if a large number is incorrectly set to "bn_nchildren". For instance, nilfs_btree_node_lookup() function determines the range of binary search with it, and too large "bn_nchildren" leads nilfs_btree_node_get_key() in that function to overrun. As for intermediate b-tree nodes, this is prevented by a sanity check performed when each node is read from a drive, however, no sanity check has been done for root nodes stored in inodes. This patch fixes the issue by adding missing sanity check against b-tree root nodes so that it's called when on-memory inodes are read from ifile, inode metadata file. Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- Reading git-diff-tree failed