From 5f8a4db715ca21c3195b5eea24e26574c0f5acfa Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 31 Jul 2017 08:50:05 +0200 Subject: [PATCH] infiniband: avoid overflow warning A sockaddr_in structure on the stack getting passed into rdma_ip2gid triggers this warning, since we memcpy into a larger sockaddr_in6 structure: In function 'memcpy', inlined from 'rdma_ip2gid' at include/rdma/ib_addr.h:175:3, inlined from 'addr_event.isra.4.constprop' at drivers/infiniband/core/roce_gid_mgmt.c:693:2, inlined from 'inetaddr_event' at drivers/infiniband/core/roce_gid_mgmt.c:716:9: include/linux/string.h:305:4: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter The warning seems appropriate here, but the code is also clearly correct, so we really just want to shut up this instance of the output. The best way I found so far is to avoid the memcpy() call and instead replace it with a struct assignment. Fixes: 6974f0c4555e ("include/linux/string.h: add the option of fortified string.h functions") Cc: Daniel Micay Cc: Kees Cook Signed-off-by: Arnd Bergmann Signed-off-by: Doug Ledford --- include/rdma/ib_addr.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/rdma/ib_addr.h b/include/rdma/ib_addr.h index b73a14edc85e..454e6ea742a5 100644 --- a/include/rdma/ib_addr.h +++ b/include/rdma/ib_addr.h @@ -172,7 +172,8 @@ static inline int rdma_ip2gid(struct sockaddr *addr, union ib_gid *gid) (struct in6_addr *)gid); break; case AF_INET6: - memcpy(gid->raw, &((struct sockaddr_in6 *)addr)->sin6_addr, 16); + *(struct in6_addr *)&gid->raw = + ((struct sockaddr_in6 *)addr)->sin6_addr; break; default: return -EINVAL; -- 2.20.1