ipc/msg.c: fix percpu_counter use after free

These percpu counters are referenced in free_ipcs->freeque, so destroy
them later.

Fixes: 72d1e61108 ("ipc/msg: mitigate the lock contention with percpu counter")
Reported-by: syzbot+96e659d35b9d6b541152@syzkaller.appspotmail.com
Tested-by: Mark Rutland <mark.rutland@arm.com>
Cc: Jiebin Sun <jiebin.sun@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Andrew Morton 2022-10-20 21:19:22 -07:00
parent 27d676a1c2
commit 64b4c411a6

View File

@ -1329,11 +1329,11 @@ fail_msg_bytes:
#ifdef CONFIG_IPC_NS #ifdef CONFIG_IPC_NS
void msg_exit_ns(struct ipc_namespace *ns) void msg_exit_ns(struct ipc_namespace *ns)
{ {
percpu_counter_destroy(&ns->percpu_msg_bytes);
percpu_counter_destroy(&ns->percpu_msg_hdrs);
free_ipcs(ns, &msg_ids(ns), freeque); free_ipcs(ns, &msg_ids(ns), freeque);
idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr); idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
rhashtable_destroy(&ns->ids[IPC_MSG_IDS].key_ht); rhashtable_destroy(&ns->ids[IPC_MSG_IDS].key_ht);
percpu_counter_destroy(&ns->percpu_msg_bytes);
percpu_counter_destroy(&ns->percpu_msg_hdrs);
} }
#endif #endif