From 17e6afc75ad0150d265a86a8f155b2871f9c07fe Mon Sep 17 00:00:00 2001 From: Dave Kleikamp Date: Tue, 9 Jan 2007 08:57:34 -0600 Subject: [PATCH] JFS: Avoid BUG() on a damaged file system On Mon, 2006-12-18 at 19:51 +0100, Eric Sesterhenn wrote: > hi, > > while playing around with fsfuzzer, i got the following oops with jfs: > > [ 851.804875] BUG at fs/jfs/jfs_xtree.c:760 > assert(!BT_STACK_FULL(btstack)) > [ 851.805179] ------------[ cut here ]------------ > [ 851.805238] kernel BUG at fs/jfs/jfs_xtree.c:760! JFS should mark the superblock dirty and return an error rather than calling BUG(). Signed-off-by: Dave Kleikamp --- fs/jfs/jfs_xtree.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/fs/jfs/jfs_xtree.c b/fs/jfs/jfs_xtree.c index e98eb03e5310..acc97c46d8a4 100644 --- a/fs/jfs/jfs_xtree.c +++ b/fs/jfs/jfs_xtree.c @@ -757,6 +757,11 @@ static int xtSearch(struct inode *ip, s64 xoff, s64 *nextp, nsplit = 0; /* push (bn, index) of the parent page/entry */ + if (BT_STACK_FULL(btstack)) { + jfs_error(ip->i_sb, "stack overrun in xtSearch!"); + XT_PUTPAGE(mp); + return -EIO; + } BT_PUSH(btstack, bn, index); /* get the child page block number */ @@ -3915,6 +3920,11 @@ s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int flag) */ getChild: /* save current parent entry for the child page */ + if (BT_STACK_FULL(&btstack)) { + jfs_error(ip->i_sb, "stack overrun in xtTruncate!"); + XT_PUTPAGE(mp); + return -EIO; + } BT_PUSH(&btstack, bn, index); /* get child page */ @@ -4112,6 +4122,11 @@ s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size) */ getChild: /* save current parent entry for the child page */ + if (BT_STACK_FULL(&btstack)) { + jfs_error(ip->i_sb, "stack overrun in xtTruncate_pmap!"); + XT_PUTPAGE(mp); + return -EIO; + } BT_PUSH(&btstack, bn, index); /* get child page */ -- 2.20.1