From 1b4654ef72f61c84704b3c79b50fdeed8747fc56 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Wed, 12 Jul 2017 14:34:50 -0700
Subject: [PATCH 05/20] ipc/sem: do not use ipc_rcu_free()
Git-commit: 1b4654ef72f61c84704b3c79b50fdeed8747fc56
Patch-mainline: v4.13-rc1
References: bsc#1050323
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 <keescook@chromium.org>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
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;
}
--
2.12.0