From cdaf25dfc058ee6f7a7b2e2353de00fa288c0cd4 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Mon, 30 Jan 2017 10:55:04 +0100
Subject: [PATCH] smc: some potential use after free bugs
Say we got really unlucky and these failed on the last iteration, then
it could lead to a use after free bug.
Fixes: cd6851f30386 ("smc: remote memory buffers (RMBs)")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/smc/smc_core.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 8b1d34378829..0eac633fb354 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -532,6 +532,7 @@ int smc_sndbuf_create(struct smc_sock *smc)
__GFP_NORETRY);
if (!sndbuf_desc->cpu_addr) {
kfree(sndbuf_desc);
+ sndbuf_desc = NULL;
/* if send buffer allocation has failed,
* try a smaller one
*/
@@ -543,6 +544,7 @@ int smc_sndbuf_create(struct smc_sock *smc)
if (rc) {
kfree(sndbuf_desc->cpu_addr);
kfree(sndbuf_desc);
+ sndbuf_desc = NULL;
continue; /* if mapping failed, try smaller one */
}
sndbuf_desc->used = 1;
@@ -596,6 +598,7 @@ int smc_rmb_create(struct smc_sock *smc)
__GFP_NORETRY);
if (!rmb_desc->cpu_addr) {
kfree(rmb_desc);
+ rmb_desc = NULL;
/* if RMB allocation has failed,
* try a smaller one
*/
@@ -607,6 +610,7 @@ int smc_rmb_create(struct smc_sock *smc)
if (rc) {
kfree(rmb_desc->cpu_addr);
kfree(rmb_desc);
+ rmb_desc = NULL;
continue; /* if mapping failed, try smaller one */
}
rc = smc_ib_get_memory_region(lgr->lnk[SMC_SINGLE_LINK].roce_pd,
@@ -619,6 +623,7 @@ int smc_rmb_create(struct smc_sock *smc)
DMA_FROM_DEVICE);
kfree(rmb_desc->cpu_addr);
kfree(rmb_desc);
+ rmb_desc = NULL;
continue;
}
rmb_desc->used = 1;