From: Erez Shitrit Date: Sun, 28 Aug 2016 07:58:30 +0000 (+0300) Subject: IB/core: Fix use after free in send_leave function X-Git-Tag: v4.8-rc6~24^2~12 X-Git-Url: http://git.cascardo.eti.br/?p=cascardo%2Flinux.git;a=commitdiff_plain;h=68c6bcdd8bd00394c234b915ab9b97c74104130c IB/core: Fix use after free in send_leave function The function send_leave sets the member: group->query_id (group->query_id = ret) after calling the sa_query, but leave_handler can be executed before the setting and it might delete the group object, and will get a memory corruption. Additionally, this patch gets rid of group->query_id variable which is not used. Fixes: faec2f7b96b5 ('IB/sa: Track multicast join/leave requests') Signed-off-by: Erez Shitrit Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford --- diff --git a/drivers/infiniband/core/multicast.c b/drivers/infiniband/core/multicast.c index 3a3c5d73bbfc..51c79b2fb0b8 100644 --- a/drivers/infiniband/core/multicast.c +++ b/drivers/infiniband/core/multicast.c @@ -106,7 +106,6 @@ struct mcast_group { atomic_t refcount; enum mcast_group_state state; struct ib_sa_query *query; - int query_id; u16 pkey_index; u8 leave_state; int retries; @@ -340,11 +339,7 @@ static int send_join(struct mcast_group *group, struct mcast_member *member) member->multicast.comp_mask, 3000, GFP_KERNEL, join_handler, group, &group->query); - if (ret >= 0) { - group->query_id = ret; - ret = 0; - } - return ret; + return (ret > 0) ? 0 : ret; } static int send_leave(struct mcast_group *group, u8 leave_state) @@ -364,11 +359,7 @@ static int send_leave(struct mcast_group *group, u8 leave_state) IB_SA_MCMEMBER_REC_JOIN_STATE, 3000, GFP_KERNEL, leave_handler, group, &group->query); - if (ret >= 0) { - group->query_id = ret; - ret = 0; - } - return ret; + return (ret > 0) ? 0 : ret; } static void join_group(struct mcast_group *group, struct mcast_member *member,