From e8d283b6cf0e83d5fcb5345e037956eb3e9b2483 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 5 Jan 2023 14:15:37 -0800 Subject: net: ipv6: rpl_iptunnel: Replace 0-length arrays with flexible arrays Zero-length arrays are deprecated[1]. Replace struct ipv6_rpl_sr_hdr's "segments" union of 0-length arrays with flexible arrays. Detected with GCC 13, using -fstrict-flex-arrays=3: In function 'rpl_validate_srh', inlined from 'rpl_build_state' at ../net/ipv6/rpl_iptunnel.c:96:7: ../net/ipv6/rpl_iptunnel.c:60:28: warning: array subscript is outside array bounds of 'struct in6_addr[0]' [-Warray-bounds=] 60 | if (ipv6_addr_type(&srh->rpl_segaddr[srh->segments_left - 1]) & | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from ../include/net/rpl.h:12, from ../net/ipv6/rpl_iptunnel.c:13: ../include/uapi/linux/rpl.h: In function 'rpl_build_state': ../include/uapi/linux/rpl.h:40:33: note: while referencing 'addr' 40 | struct in6_addr addr[0]; | ^~~~ [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays Cc: Hideaki YOSHIFUJI Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20230105221533.never.711-kees@kernel.org Signed-off-by: Jakub Kicinski --- include/uapi/linux/rpl.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/rpl.h b/include/uapi/linux/rpl.h index 708adddf9f13..7c8970e5b84b 100644 --- a/include/uapi/linux/rpl.h +++ b/include/uapi/linux/rpl.h @@ -37,8 +37,8 @@ struct ipv6_rpl_sr_hdr { #endif union { - struct in6_addr addr[0]; - __u8 data[0]; + __DECLARE_FLEX_ARRAY(struct in6_addr, addr); + __DECLARE_FLEX_ARRAY(__u8, data); } segments; } __attribute__((packed)); -- cgit v1.2.3