[Qemu-devel] [PULL 1/3] slirp: Avoid unaligned 16bit memory access

Samuel Thibault posted 3 patches 6 years, 9 months ago
Maintainers: Jan Kiszka <jan.kiszka@siemens.com>, Samuel Thibault <samuel.thibault@ens-lyon.org>
[Qemu-devel] [PULL 1/3] slirp: Avoid unaligned 16bit memory access
Posted by Samuel Thibault 6 years, 9 months ago
pkt parameter may be unaligned, so we must access it byte-wise.

This fixes sparc64 host SIGBUS during pxe boot.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 slirp/slirp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/slirp/slirp.c b/slirp/slirp.c
index a9674ab090..739f364770 100644
--- a/slirp/slirp.c
+++ b/slirp/slirp.c
@@ -829,7 +829,7 @@ void slirp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
     if (pkt_len < ETH_HLEN)
         return;
 
-    proto = ntohs(*(uint16_t *)(pkt + 12));
+    proto = (((uint16_t) pkt[12]) << 8) + pkt[13];
     switch(proto) {
     case ETH_P_ARP:
         arp_input(slirp, pkt, pkt_len);
-- 
2.20.1