flow_dissector: Fix out-of-bounds warnings
Fix the following out-of-bounds warnings: net/core/flow_dissector.c: In function '__skb_flow_dissect': >> net/core/flow_dissector.c:1104:4: warning: 'memcpy' offset [24, 39] from the object at '<unknown>' is out of the bounds of referenced subobject 'saddr' with type 'struct in6_addr' at offset 8 [-Warray-bounds] 1104 | memcpy(&key_addrs->v6addrs, &iph->saddr, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1105 | sizeof(key_addrs->v6addrs)); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from include/linux/ipv6.h:5, from net/core/flow_dissector.c:6: include/uapi/linux/ipv6.h:133:18: note: subobject 'saddr' declared here 133 | struct in6_addr saddr; | ^~~~~ >> net/core/flow_dissector.c:1059:4: warning: 'memcpy' offset [16, 19] from the object at '<unknown>' is out of the bounds of referenced subobject 'saddr' with type 'unsigned int' at offset 12 [-Warray-bounds] 1059 | memcpy(&key_addrs->v4addrs, &iph->saddr, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1060 | sizeof(key_addrs->v4addrs)); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from include/linux/ip.h:17, from net/core/flow_dissector.c:5: include/uapi/linux/ip.h:103:9: note: subobject 'saddr' declared here 103 | __be32 saddr; | ^~~~~ The problem is that the original code is trying to copy data into a couple of struct members adjacent to each other in a single call to memcpy(). So, the compiler legitimately complains about it. As these are just a couple of members, fix this by copying each one of them in separate calls to memcpy(). This helps with the ongoing efforts to globally enable -Warray-bounds and get us closer to being able to tighten the FORTIFY_SOURCE routines on memcpy(). Link: https://github.com/KSPP/linux/issues/109 Reported-by:kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/lkml/d5ae2e65-1f18-2577-246f-bada7eee6ccd@intel.com/ Signed-off-by:
Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by:
David S. Miller <davem@davemloft.net>
parent
6321c7ac