From 2618a0dae09ef37728dab89ff60418cbe25ae6bd Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Sat, 12 Feb 2022 09:14:49 -0800 Subject: etherdevice: Adjust ether_addr* prototypes to silence -Wstringop-overead MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With GCC 12, -Wstringop-overread was warning about an implicit cast from char[6] to char[8]. However, the extra 2 bytes are always thrown away, alignment doesn't matter, and the risk of hitting the edge of unallocated memory has been accepted, so this prototype can just be converted to a regular char *. Silences: net/core/dev.c: In function ‘bpf_prog_run_generic_xdp’: net/core/dev.c:4618:21: warning: ‘ether_addr_equal_64bits’ reading 8 bytes from a region of size 6 [-Wstringop-overread] 4618 | orig_host = ether_addr_equal_64bits(eth->h_dest, > skb->dev->dev_addr); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ net/core/dev.c:4618:21: note: referencing argument 1 of type ‘const u8[8]’ {aka ‘const unsigned char[8]’} net/core/dev.c:4618:21: note: referencing argument 2 of type ‘const u8[8]’ {aka ‘const unsigned char[8]’} In file included from net/core/dev.c:91: include/linux/etherdevice.h:375:20: note: in a call to function ‘ether_addr_equal_64bits’ 375 | static inline bool ether_addr_equal_64bits(const u8 addr1[6+2], | ^~~~~~~~~~~~~~~~~~~~~~~ Reported-by: Marc Kleine-Budde Tested-by: Marc Kleine-Budde Link: https://lore.kernel.org/netdev/20220212090811.uuzk6d76agw2vv73@pengutronix.de Cc: Jakub Kicinski Cc: "David S. Miller" Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'include/linux/etherdevice.h') diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 2ad71cc90b37..92b10e67d5f8 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -134,7 +134,7 @@ static inline bool is_multicast_ether_addr(const u8 *addr) #endif } -static inline bool is_multicast_ether_addr_64bits(const u8 addr[6+2]) +static inline bool is_multicast_ether_addr_64bits(const u8 *addr) { #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 #ifdef __BIG_ENDIAN @@ -372,8 +372,7 @@ static inline bool ether_addr_equal(const u8 *addr1, const u8 *addr2) * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits. */ -static inline bool ether_addr_equal_64bits(const u8 addr1[6+2], - const u8 addr2[6+2]) +static inline bool ether_addr_equal_64bits(const u8 *addr1, const u8 *addr2) { #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 u64 fold = (*(const u64 *)addr1) ^ (*(const u64 *)addr2); -- cgit v1.2.3 From e8013f8edaa30e17fd583a326daff1fa86b75c82 Mon Sep 17 00:00:00 2001 From: Casper Andersson Date: Thu, 25 Aug 2022 11:28:35 +0200 Subject: ethernet: Add helpers to recognize addresses mapped to IP multicast IP multicast must sometimes be discriminated from non-IP multicast, e.g. when determining the forwarding behavior of a given group in the presence of multicast router ports on an offloaded bridge. Therefore, provide helpers to identify these groups. Signed-off-by: Casper Andersson Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'include/linux/etherdevice.h') diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 92b10e67d5f8..a541f0c4f146 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -428,6 +428,28 @@ static inline bool ether_addr_equal_masked(const u8 *addr1, const u8 *addr2, return true; } +static inline bool ether_addr_is_ipv4_mcast(const u8 *addr) +{ + u8 base[ETH_ALEN] = { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 }; + u8 mask[ETH_ALEN] = { 0xff, 0xff, 0xff, 0x80, 0x00, 0x00 }; + + return ether_addr_equal_masked(addr, base, mask); +} + +static inline bool ether_addr_is_ipv6_mcast(const u8 *addr) +{ + u8 base[ETH_ALEN] = { 0x33, 0x33, 0x00, 0x00, 0x00, 0x00 }; + u8 mask[ETH_ALEN] = { 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 }; + + return ether_addr_equal_masked(addr, base, mask); +} + +static inline bool ether_addr_is_ip_mcast(const u8 *addr) +{ + return ether_addr_is_ipv4_mcast(addr) || + ether_addr_is_ipv6_mcast(addr); +} + /** * ether_addr_to_u64 - Convert an Ethernet address into a u64 value. * @addr: Pointer to a six-byte array containing the Ethernet address -- cgit v1.2.3