Commit 35f9ac2d authored Nov 08, 2012 by majianpeng Committed by NeilBrown Nov 20, 2012

md: Avoid write invalid address if read_seqretry returned true.



If read_seqretry returned true and bbp was changed, it will write
invalid address which can cause some serious problem.

This bug was introduced by commit v3.0-rc7-130-g2699b67.
So fix is suitable for 3.0.y thru 3.6.y.

Reported-by:  <zhuwenfeng@kedacom.com>
Tested-by:  <zhuwenfeng@kedacom.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

parent ab05613a

drivers/md/md.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1817,10 +1817,10 @@ retry:
		memset(bbp, 0xff, PAGE_SIZE);

		for (i = 0 ; i < bb->count ; i++) {
		u64 internal_bb = *p++;
		u64 internal_bb = p[i];
		u64 store_bb = ((BB_OFFSET(internal_bb) << 10)
		\| BB_LEN(internal_bb));
		*bbp++ = cpu_to_le64(store_bb);
		bbp[i] = cpu_to_le64(store_bb);
		}
		bb->changed = 0;
		if (read_seqretry(&bb->lock, seq))

Admin message