jffs2: hold erase_completion_lock on exit

commit 2cbba75a56 upstream.

Users of jffs2_do_reserve_space() expect they still held
erase_completion_lock after call to it. But there is a path
where jffs2_do_reserve_space() leaves erase_completion_lock unlocked.
The patch fixes it.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alexey Khoroshilov 2012-11-05 22:40:14 +04:00 committed by Greg Kroah-Hartman
parent 113b47f82d
commit 43f5d330de

View File

@ -355,14 +355,16 @@ static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
spin_unlock(&c->erase_completion_lock);
ret = jffs2_prealloc_raw_node_refs(c, jeb, 1);
if (ret)
return ret;
/* Just lock it again and continue. Nothing much can change because
we hold c->alloc_sem anyway. In fact, it's not entirely clear why
we hold c->erase_completion_lock in the majority of this function...
but that's a question for another (more caffeine-rich) day. */
spin_lock(&c->erase_completion_lock);
if (ret)
return ret;
waste = jeb->free_size;
jffs2_link_node_ref(c, jeb,
(jeb->offset + c->sector_size - waste) | REF_OBSOLETE,