[04/11] ath11: Wstringop-overread warning

Commit Message

Arnd Bergmann March 22, 2021, 4:02 p.m. UTC

From: Arnd Bergmann <[e-mail]>

gcc-11 with the kernel address sanitizer prints a warning for this
driver:

In function 'ath11k_peer_assoc_h_vht',
    inlined from 'ath11k_peer_assoc_prepare' at drivers/net/wireless/ath/ath11k/mac.c:1632:2:
drivers/net/wireless/ath/ath11k/mac.c:1164:13: error: 'ath11k_peer_assoc_h_vht_masked' reading 16 bytes from a region of size 4 [-Werror=stringop-overread]
 1164 |         if (ath11k_peer_assoc_h_vht_masked(vht_mcs_mask))
      |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/ath/ath11k/mac.c: In function 'ath11k_peer_assoc_prepare':
drivers/net/wireless/ath/ath11k/mac.c:1164:13: note: referencing argument 1 of type 'const u16 *' {aka 'const short unsigned int *'}
drivers/net/wireless/ath/ath11k/mac.c:969:1: note: in a call to function 'ath11k_peer_assoc_h_vht_masked'
  969 | ath11k_peer_assoc_h_vht_masked(const u16 vht_mcs_mask[NL80211_VHT_NSS_MAX])
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

According to analysis from gcc developers, this is a glitch in the
way gcc tracks the size of struct members. This should really get
fixed in gcc, but it's also easy to work around this instance
by changing the function prototype to no include the length of
the array.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99673
Signed-off-by: Arnd Bergmann <[e-mail]>
---
 drivers/net/wireless/ath/ath11k/mac.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Kalle Valo Sept. 28, 2021, 9:04 a.m. UTC | #1

Arnd Bergmann <[e-mail]> wrote:

> gcc-11 with the kernel address sanitizer prints a warning for this
> driver:
> 
> In function 'ath11k_peer_assoc_h_vht',
>     inlined from 'ath11k_peer_assoc_prepare' at drivers/net/wireless/ath/ath11k/mac.c:1632:2:
> drivers/net/wireless/ath/ath11k/mac.c:1164:13: error: 'ath11k_peer_assoc_h_vht_masked' reading 16 bytes from a region of size 4 [-Werror=stringop-overread]
>  1164 |         if (ath11k_peer_assoc_h_vht_masked(vht_mcs_mask))
>       |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/ath/ath11k/mac.c: In function 'ath11k_peer_assoc_prepare':
> drivers/net/wireless/ath/ath11k/mac.c:1164:13: note: referencing argument 1 of type 'const u16 *' {aka 'const short unsigned int *'}
> drivers/net/wireless/ath/ath11k/mac.c:969:1: note: in a call to function 'ath11k_peer_assoc_h_vht_masked'
>   969 | ath11k_peer_assoc_h_vht_masked(const u16 vht_mcs_mask[NL80211_VHT_NSS_MAX])
>       | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> According to analysis from gcc developers, this is a glitch in the
> way gcc tracks the size of struct members. This should really get
> fixed in gcc, but it's also easy to work around this instance
> by changing the function prototype to no include the length of
> the array.
> 
> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99673
> Signed-off-by: Arnd Bergmann <[e-mail]>
> Signed-off-by: Kalle Valo <[e-mail]>

Patch applied to ath-next branch of ath.git, thanks.

eb19efed836a ath11k: Wstringop-overread warning

Patch

diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index b391169576e2..5cb7ed53f3c4 100644
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -966,7 +966,7 @@  ath11k_peer_assoc_h_ht_masked(const u8 ht_mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
 }
 
 static bool
-ath11k_peer_assoc_h_vht_masked(const u16 vht_mcs_mask[NL80211_VHT_NSS_MAX])
+ath11k_peer_assoc_h_vht_masked(const u16 vht_mcs_mask[])
 {
 	int nss;