From d3847ac2c5d194e9bcae34f613796332c38ec511 Mon Sep 17 00:00:00 2001 From: Rahul Bhansali Date: Tue, 11 Jan 2022 18:20:05 +0530 Subject: [PATCH] examples/l3fwd: fix buffer overflow in Tx [ upstream commit 0490d69d58d9d75c37e780966c837a062658f528 ] This patch fixes the stack buffer overflow error reported from AddressSanitizer. Function send_packetsx4() tries to access out of bound data from rte_mbuf and fill it into TX buffer even in the case where no pending packets (len = 0). Performance impact:- No ASAN error report:- ==819==ERROR: AddressSanitizer: stack-buffer-overflow on address 0xffffe2c0dcf0 at pc 0x0000005e791c bp 0xffffe2c0d7e0 sp 0xffffe2c0d800 READ of size 8 at 0xffffe2c0dcf0 thread T0 #0 0x5e7918 in send_packetsx4 ../examples/l3fwd/l3fwd_common.h:251 #1 0x5e7918 in send_packets_multi ../examples/l3fwd/l3fwd_neon.h:226 Fixes: 96ff445371e0 ("examples/l3fwd: reorganise and optimize LPM code path") Signed-off-by: Rahul Bhansali Reviewed-by: Conor Walsh Acked-by: Konstantin Ananyev --- examples/l3fwd/l3fwd_common.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/examples/l3fwd/l3fwd_common.h b/examples/l3fwd/l3fwd_common.h index 7d83ff641a..de77711f88 100644 --- a/examples/l3fwd/l3fwd_common.h +++ b/examples/l3fwd/l3fwd_common.h @@ -236,6 +236,9 @@ send_packetsx4(struct lcore_conf *qconf, uint16_t port, struct rte_mbuf *m[], /* copy rest of the packets into the TX buffer. */ len = num - n; + if (len == 0) + goto exit; + j = 0; switch (len % FWDSTEP) { while (j < len) { @@ -258,6 +261,7 @@ send_packetsx4(struct lcore_conf *qconf, uint16_t port, struct rte_mbuf *m[], } } +exit: qconf->tx_mbufs[port].len = len; }