From b5d8cf0af167f3ab9f4cfe44918cde01e20a1222 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 18 Nov 2021 12:34:07 -0800 Subject: [PATCH] net/af_iucv: Use struct_group() to zero struct iucv_sock region In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields. Add struct_group() to mark the region of struct iucv_sock that gets initialized to zero. Avoid the future warning: In function 'fortify_memset_chk', inlined from 'iucv_sock_alloc' at net/iucv/af_iucv.c:476:2: ./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning] 199 | __write_overflow_field(p_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Acked-by: Karsten Graul Link: https://lore.kernel.org/lkml/19ff61a0-0cda-6000-ce56-dc6b367c00d6@linux.ibm.com/ Signed-off-by: Kees Cook Signed-off-by: David S. Miller --- include/net/iucv/af_iucv.h | 10 ++++++---- net/iucv/af_iucv.c | 2 +- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/include/net/iucv/af_iucv.h b/include/net/iucv/af_iucv.h index ff06246..df85d19 100644 --- a/include/net/iucv/af_iucv.h +++ b/include/net/iucv/af_iucv.h @@ -112,10 +112,12 @@ enum iucv_tx_notify { struct iucv_sock { struct sock sk; - char src_user_id[8]; - char src_name[8]; - char dst_user_id[8]; - char dst_name[8]; + struct_group(init, + char src_user_id[8]; + char src_name[8]; + char dst_user_id[8]; + char dst_name[8]; + ); struct list_head accept_q; spinlock_t accept_q_lock; struct sock *parent; diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c index 996ccf3..49ecbe8 100644 --- a/net/iucv/af_iucv.c +++ b/net/iucv/af_iucv.c @@ -473,7 +473,7 @@ static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, atomic_set(&iucv->msg_recv, 0); iucv->path = NULL; iucv->sk_txnotify = afiucv_hs_callback_txnotify; - memset(&iucv->src_user_id , 0, 32); + memset(&iucv->init, 0, sizeof(iucv->init)); if (pr_iucv) iucv->transport = AF_IUCV_TRANS_IUCV; else -- 2.7.4