drm/ttm: fix bulk_move corruption when adding a entry

commit 4481913607e58196c48a4fef5e6f45350684ec3c upstream.

When the resource is the first in the bulk_move range, adding it again
(thus moving it to the tail) will corrupt the list since the first
pointer is not moved. This eventually lead to null pointer deref in
ttm_lru_bulk_move_del()

Fixes: fee2ede155 ("drm/ttm: rework bulk move handling v5")
Signed-off-by: Yunxiang Li <Yunxiang.Li@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
CC: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20230622141902.28718-3-Yunxiang.Li@amd.com
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Yunxiang Li 2023-06-22 10:18:03 -04:00 committed by Greg Kroah-Hartman
parent 61622fa379
commit 70a3015683

View File

@ -85,6 +85,8 @@ static void ttm_lru_bulk_move_pos_tail(struct ttm_lru_bulk_move_pos *pos,
struct ttm_resource *res)
{
if (pos->last != res) {
if (pos->first == res)
pos->first = list_next_entry(res, lru);
list_move(&res->lru, &pos->last->lru);
pos->last = res;
}
@ -110,7 +112,8 @@ static void ttm_lru_bulk_move_del(struct ttm_lru_bulk_move *bulk,
{
struct ttm_lru_bulk_move_pos *pos = ttm_lru_bulk_move_pos(bulk, res);
if (unlikely(pos->first == res && pos->last == res)) {
if (unlikely(WARN_ON(!pos->first || !pos->last) ||
(pos->first == res && pos->last == res))) {
pos->first = NULL;
pos->last = NULL;
} else if (pos->first == res) {