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@xxxxxxxxxx>
---
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(-)
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);
