lkml.org 
[lkml]   [2019]   [Dec]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.14 052/267] net/smc: use after free fix in smc_wr_tx_put_slot()
Date
From: Ursula Braun <ursula.braun@linux.ibm.com>

[ Upstream commit e438bae43c1e08e688c09c410407b59fc1c173b4 ]

In smc_wr_tx_put_slot() field pend->idx is used after being
cleared. That means always idx 0 is cleared in the wr_tx_mask.
This results in a broken administration of available WR send
payload buffers.

Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/smc/smc_wr.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/smc/smc_wr.c b/net/smc/smc_wr.c
index de4537f66832a..ed6736a1a112e 100644
--- a/net/smc/smc_wr.c
+++ b/net/smc/smc_wr.c
@@ -223,12 +223,14 @@ int smc_wr_tx_put_slot(struct smc_link *link,

pend = container_of(wr_pend_priv, struct smc_wr_tx_pend, priv);
if (pend->idx < link->wr_tx_cnt) {
+ u32 idx = pend->idx;
+
/* clear the full struct smc_wr_tx_pend including .priv */
memset(&link->wr_tx_pends[pend->idx], 0,
sizeof(link->wr_tx_pends[pend->idx]));
memset(&link->wr_tx_bufs[pend->idx], 0,
sizeof(link->wr_tx_bufs[pend->idx]));
- test_and_clear_bit(pend->idx, link->wr_tx_mask);
+ test_and_clear_bit(idx, link->wr_tx_mask);
return 1;
}

--
2.20.1


\
 
 \ /
  Last update: 2019-12-16 18:53    [W:0.488 / U:8.764 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site