From 2374aee49483447aff3fb330d5e8ee60fa0c9234 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Mon, 3 Feb 2014 12:13:07 -0500 Subject: [PATCH] locks: eliminate BUG() call when there's an unexpected lock on file close commit 8c3cac5e6a85f03602ffe09c44f14418699e31ec upstream. A leftover lock on the list is surely a sign of a problem of some sort, but it's not necessarily a reason to panic the box. Instead, just log a warning with some info about the lock, and then delete it like we would any other lock. In the event that the filesystem declares a ->lock f_op, we may end up leaking something, but that's generally preferable to an immediate panic. Acked-by: J. Bruce Fields Signed-off-by: Jeff Layton Cc: Markus Blank-Burian Signed-off-by: Greg Kroah-Hartman --- fs/locks.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index 4dd39b9..2c61c4e 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -2235,16 +2235,28 @@ void locks_remove_flock(struct file *filp) while ((fl = *before) != NULL) { if (fl->fl_file == filp) { - if (IS_FLOCK(fl)) { - locks_delete_lock(before); - continue; - } if (IS_LEASE(fl)) { lease_modify(before, F_UNLCK); continue; } - /* What? */ - BUG(); + + /* + * There's a leftover lock on the list of a type that + * we didn't expect to see. Most likely a classic + * POSIX lock that ended up not getting released + * properly, or that raced onto the list somehow. Log + * some info about it and then just remove it from + * the list. + */ + WARN(!IS_FLOCK(fl), + "leftover lock: dev=%u:%u ino=%lu type=%hhd flags=0x%x start=%lld end=%lld\n", + MAJOR(inode->i_sb->s_dev), + MINOR(inode->i_sb->s_dev), inode->i_ino, + fl->fl_type, fl->fl_flags, + fl->fl_start, fl->fl_end); + + locks_delete_lock(before); + continue; } before = &fl->fl_next; } -- 2.7.4