From 1b4654ef72f61c84704b3c79b50fdeed8747fc56 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 12 Jul 2017 14:34:50 -0700 Subject: [PATCH] ipc/sem: do not use ipc_rcu_free() Avoid using ipc_rcu_free, since it just re-finds the original structure pointer. For the pre-list-init failure path, there is no RCU needed, since it was just allocated. It can be directly freed. Link: http://lkml.kernel.org/r/20170525185107.12869-6-manfred@colorfullife.com Signed-off-by: Kees Cook Signed-off-by: Manfred Spraul Cc: Davidlohr Bueso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/sem.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/ipc/sem.c b/ipc/sem.c index 484ccf83cf85..a04c4d6d120c 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -258,13 +258,18 @@ static void merge_queues(struct sem_array *sma) } } +static void __sem_free(struct sem_array *sma) +{ + kvfree(sma); +} + static void sem_rcu_free(struct rcu_head *head) { struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu); struct sem_array *sma = container_of(p, struct sem_array, sem_perm); security_sem_free(sma); - ipc_rcu_free(head); + __sem_free(sma); } /* @@ -482,7 +487,7 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_perm.security = NULL; retval = security_sem_alloc(sma); if (retval) { - ipc_rcu_putref(&sma->sem_perm, ipc_rcu_free); + __sem_free(sma); return retval; } -- 2.20.1