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etherdevice: Adjust ether_addr* prototypes to silence -Wstringop-overead

Eric Chanudet requested to merge echanude/centos-stream-9:net/bz2142659 into main

Bugzilla: https://bugzilla.redhat.com/2142659

commit 2618a0dae09ef37728dab89ff60418cbe25ae6bd
Author: Kees Cook keescook@chromium.org
Date: Sat Feb 12 09:14:49 2022 -0800

etherdevice: Adjust ether_addr* prototypes to silence -Wstringop-overead  

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 <mkl@pengutronix.de>  
Tested-by: Marc Kleine-Budde <mkl@pengutronix.de>  
Link: https://lore.kernel.org/netdev/20220212090811.uuzk6d76agw2vv73@pengutronix.de  
Cc: Jakub Kicinski <kuba@kernel.org>  
Cc: "David S. Miller" <davem@davemloft.net>  
Cc: netdev@vger.kernel.org  
Signed-off-by: Kees Cook <keescook@chromium.org>  
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Eric Chanudet echanude@redhat.com

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