Commit 25601a3c authored Jul 30, 2014 by hujianyang Committed by Artem Bityutskiy Jul 31, 2014

UBIFS: Add log overlap assertions



We use a circle area to record the log nodes in ubifs. This log area
should not be overlapped. But after researching the code, I found
some conditions may lead log head wraps log ltail. Although we've
fixed the problems discovered, there may be some other issues still
left.

This patch adds assertions where lhead changes to next leb to make
sure ltail is not wrapped.

Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

parent 6390e991

fs/ubifs/log.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -240,6 +240,7 @@ int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs)

		if (c->lhead_offs > c->leb_size - c->ref_node_alsz) {
		c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
		ubifs_assert(c->lhead_lnum != c->ltail_lnum);
		c->lhead_offs = 0;
		}

		@@ -404,6 +405,7 @@ int ubifs_log_start_commit(struct ubifs_info c, int ltail_lnum)
		/* Switch to the next log LEB */
		if (c->lhead_offs) {
		c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
		ubifs_assert(c->lhead_lnum != c->ltail_lnum);
		c->lhead_offs = 0;
		}