[PATCH net] wifi: ath12k: fix build vs old compiler

[Jeff Johnson]

On 7/16/2024 4:06 AM, Paolo Abeni wrote:
> gcc 11.4.1-3 warns about memcpy() with overlapping pointers:
> 
> drivers/net/wireless/ath/ath12k/wow.c: In function ‘ath12k_wow_convert_8023_to_80211.constprop’:
> ./include/linux/fortify-string.h:114:33: error: ‘__builtin_memcpy’ accessing 18446744073709551611 or more bytes at offsets 0 and 0 overlaps 9223372036854775799 bytes at offset -9223372036854775804 [-Werror=restrict]
>   114 | #define __underlying_memcpy     __builtin_memcpy
>       |                                 ^
> ./include/linux/fortify-string.h:637:9: note: in expansion of macro ‘__underlying_memcpy’
>   637 |         __underlying_##op(p, q, __fortify_size);                        \
>       |         ^~~~~~~~~~~~~
> ./include/linux/fortify-string.h:682:26: note: in expansion of macro ‘__fortify_memcpy_chk’
>   682 | #define memcpy(p, q, s)  __fortify_memcpy_chk(p, q, s,                  \
>       |                          ^~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/ath/ath12k/wow.c:190:25: note: in expansion of macro ‘memcpy’
>   190 |                         memcpy(pat, eth_pat, eth_pat_len);
>       |                         ^~~~~~
> ./include/linux/fortify-string.h:114:33: error: ‘__builtin_memcpy’ accessing 18446744073709551605 or more bytes at offsets 0 and 0 overlaps 9223372036854775787 bytes at offset -9223372036854775798 [-Werror=restrict]
>   114 | #define __underlying_memcpy     __builtin_memcpy
>       |                                 ^
> ./include/linux/fortify-string.h:637:9: note: in expansion of macro ‘__underlying_memcpy’
>   637 |         __underlying_##op(p, q, __fortify_size);                        \
>       |         ^~~~~~~~~~~~~
> ./include/linux/fortify-string.h:682:26: note: in expansion of macro ‘__fortify_memcpy_chk’
>   682 | #define memcpy(p, q, s)  __fortify_memcpy_chk(p, q, s,                  \
>       |                          ^~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/ath/ath12k/wow.c:232:25: note: in expansion of macro ‘memcpy’
>   232 |                         memcpy(pat, eth_pat, eth_pat_len);
>       |                         ^~~~~~
> 
> The sum of size_t operands can overflow SIZE_MAX, triggering the
> warning.
> Address the issue using the suitable helper.
> 
> Fixes: 4a3c212eee0e ("wifi: ath12k: add basic WoW functionalities")
> Signed-off-by: Paolo Abeni <pabeni at redhat.com>
> ---
> Only built tested. Sending directly to net to reduce the RTT, but no
> objections to go through the WiFi tree first

Since Kalle is on holiday please go ahead and take this via net.
This looks nicer than Kalle's version :)

Acked-by: Jeff Johnson <quic_jjohnson at quicinc.com>