diff mbox series

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

Message ID 3175f87d7227e395b330fd88fb840c1645084ea7.1721127979.git.pabeni@redhat.com
State New
Headers show
Series [net] wifi: ath12k: fix build vs old compiler | expand

Commit Message

Paolo Abeni July 16, 2024, 11:06 a.m. UTC
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@redhat.com>
---
Only built tested. Sending directly to net to reduce the RTT, but no
objections to go through the WiFi tree first
---
 drivers/net/wireless/ath/ath12k/wow.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Kalle Valo July 31, 2024, 4:11 p.m. UTC | #1
Jeff Johnson <quic_jjohnson@quicinc.com> writes:

> 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@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 :)

Indeed, this is nicer. Thanks Paolo!
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath12k/wow.c b/drivers/net/wireless/ath/ath12k/wow.c
index c5cba825a84a..bead19db2c9a 100644
--- a/drivers/net/wireless/ath/ath12k/wow.c
+++ b/drivers/net/wireless/ath/ath12k/wow.c
@@ -186,7 +186,7 @@  ath12k_wow_convert_8023_to_80211(struct ath12k *ar,
 	if (eth_pkt_ofs < ETH_ALEN) {
 		pkt_ofs = eth_pkt_ofs + a1_ofs;
 
-		if (eth_pkt_ofs + eth_pat_len < ETH_ALEN) {
+		if (size_add(eth_pkt_ofs, eth_pat_len) < ETH_ALEN) {
 			memcpy(pat, eth_pat, eth_pat_len);
 			memcpy(bytemask, eth_bytemask, eth_pat_len);
 
@@ -228,7 +228,7 @@  ath12k_wow_convert_8023_to_80211(struct ath12k *ar,
 	} else if (eth_pkt_ofs < prot_ofs) {
 		pkt_ofs = eth_pkt_ofs - ETH_ALEN + a3_ofs;
 
-		if (eth_pkt_ofs + eth_pat_len < prot_ofs) {
+		if (size_add(eth_pkt_ofs, eth_pat_len) < prot_ofs) {
 			memcpy(pat, eth_pat, eth_pat_len);
 			memcpy(bytemask, eth_bytemask, eth_pat_len);