ocfs2: fix snprintf() checking
authorDan Carpenter <dan.carpenter@oracle.com>
Tue, 29 Jun 2021 02:34:01 +0000 (19:34 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 29 Jun 2021 17:53:46 +0000 (10:53 -0700)
commit54e948c60cc843b6e84dc44496edc91f51d2a28e
tree8646317910cb0caee63fd930ef3e02d6222dea88
parent74ef829e41be8ada93e1d1dfa681c11be338c8d5
ocfs2: fix snprintf() checking

The snprintf() function returns the number of bytes which would have been
printed if the buffer was large enough.  In other words it can return ">=
remain" but this code assumes it returns "== remain".

The run time impact of this bug is not very severe.  The next iteration
through the loop would trigger a WARN() when we pass a negative limit to
snprintf().  We would then return success instead of -E2BIG.

The kernel implementation of snprintf() will never return negatives so
there is no need to check and I have deleted that dead code.

Link: https://lkml.kernel.org/r/20210511135350.GV1955@kadam
Fixes: a860f6eb4c6a ("ocfs2: sysfile interfaces for online file check")
Fixes: 74ae4e104dfc ("ocfs2: Create stack glue sysfs files.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ocfs2/filecheck.c
fs/ocfs2/stackglue.c