From: Arnd Bergmann arnd@arndb.de
[ Upstream commit 61752ac69b69ed2e04444d090f6917c77ab36d42 ]
gcc-9 and some other older versions produce a false-positive warning for zeroing two fields
In file included from include/linux/string.h:369, from drivers/net/wireless/ath/ath9k/main.c:18: In function 'fortify_memset_chk', inlined from 'ath9k_ps_wakeup' at drivers/net/wireless/ath/ath9k/main.c:140:3: include/linux/fortify-string.h:462:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning] 462 | __write_overflow_field(p_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Using a struct_group seems to reliably avoid the warning and not make the code much uglier. The combined memset() should even save a couple of cpu cycles.
Signed-off-by: Arnd Bergmann arnd@arndb.de Acked-by: Toke Høiland-Jørgensen toke@toke.dk Reviewed-by: Kees Cook keescook@chromium.org Signed-off-by: Kalle Valo quic_kvalo@quicinc.com Link: https://msgid.link/20240328135509.3755090-3-arnd@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/ath/ath.h | 6 ++++-- drivers/net/wireless/ath/ath9k/main.c | 3 +-- 2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/ath/ath.h b/drivers/net/wireless/ath/ath.h index f02a308a9ffc5..34654f710d8a1 100644 --- a/drivers/net/wireless/ath/ath.h +++ b/drivers/net/wireless/ath/ath.h @@ -171,8 +171,10 @@ struct ath_common { unsigned int clockrate;
spinlock_t cc_lock; - struct ath_cycle_counters cc_ani; - struct ath_cycle_counters cc_survey; + struct_group(cc, + struct ath_cycle_counters cc_ani; + struct ath_cycle_counters cc_survey; + );
struct ath_regulatory regulatory; struct ath_regulatory reg_world_copy; diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index 1494feedb27db..aa271b82875e0 100644 --- a/drivers/net/wireless/ath/ath9k/main.c +++ b/drivers/net/wireless/ath/ath9k/main.c @@ -135,8 +135,7 @@ void ath9k_ps_wakeup(struct ath_softc *sc) if (power_mode != ATH9K_PM_AWAKE) { spin_lock(&common->cc_lock); ath_hw_cycle_counters_update(common); - memset(&common->cc_survey, 0, sizeof(common->cc_survey)); - memset(&common->cc_ani, 0, sizeof(common->cc_ani)); + memset(&common->cc, 0, sizeof(common->cc)); spin_unlock(&common->cc_lock); }