* [PATCH 1/2] b43legacy: fix a lower bounds test
@ 2021-10-06 7:35 Dan Carpenter
2021-10-06 7:36 ` [PATCH 2/2] b43: " Dan Carpenter
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: Dan Carpenter @ 2021-10-06 7:35 UTC (permalink / raw)
To: Larry Finger; +Cc: Kalle Valo, linux-wireless, b43-dev, kernel-janitors
The problem is that "channel" is an unsigned int, when it's less 5 the
value of "channel - 5" is not a negative number as one would expect but
is very high positive value instead.
This means that "start" becomes a very high positive value. The result
of that is that we never enter the "for (i = start; i <= end; i++) {"
loop. Instead of storing the result from b43legacy_radio_aci_detect()
it just uses zero.
Fixes: 75388acd0cd8 ("[B43LEGACY]: add mac80211-based driver for legacy BCM43xx devices")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
This fix is correct, but making dead code go live can sometimes expose
bugs which were previously hiding and is always carries a slight risk.
drivers/net/wireless/broadcom/b43legacy/radio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/broadcom/b43legacy/radio.c b/drivers/net/wireless/broadcom/b43legacy/radio.c
index 06891b4f837b..fdf78c10a05c 100644
--- a/drivers/net/wireless/broadcom/b43legacy/radio.c
+++ b/drivers/net/wireless/broadcom/b43legacy/radio.c
@@ -283,7 +283,7 @@ u8 b43legacy_radio_aci_scan(struct b43legacy_wldev *dev)
& 0x7FFF);
b43legacy_set_all_gains(dev, 3, 8, 1);
- start = (channel - 5 > 0) ? channel - 5 : 1;
+ start = (channel > 5) ? channel - 5 : 1;
end = (channel + 5 < 14) ? channel + 5 : 13;
for (i = start; i <= end; i++) {
--
2.20.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH 2/2] b43: fix a lower bounds test
2021-10-06 7:35 [PATCH 1/2] b43legacy: fix a lower bounds test Dan Carpenter
@ 2021-10-06 7:36 ` Dan Carpenter
2021-10-06 16:13 ` Michael Büsch
2021-10-06 16:13 ` [PATCH 1/2] b43legacy: " Michael Büsch
2021-10-11 6:09 ` Kalle Valo
2 siblings, 1 reply; 5+ messages in thread
From: Dan Carpenter @ 2021-10-06 7:36 UTC (permalink / raw)
To: Kalle Valo
Cc: John W. Linville, Michael Buesch, linux-wireless, b43-dev,
kernel-janitors
The problem is that "channel" is an unsigned int, when it's less 5 the
value of "channel - 5" is not a negative number as one would expect but
is very high positive value instead.
This means that "start" becomes a very high positive value. The result
of that is that we never enter the "for (i = start; i <= end; i++) {"
loop. Instead of storing the result from b43legacy_radio_aci_detect()
it just uses zero.
Fixes: ef1a628d83fc ("b43: Implement dynamic PHY API")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
drivers/net/wireless/broadcom/b43/phy_g.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/broadcom/b43/phy_g.c b/drivers/net/wireless/broadcom/b43/phy_g.c
index d5a1a5c58236..ac72ca39e409 100644
--- a/drivers/net/wireless/broadcom/b43/phy_g.c
+++ b/drivers/net/wireless/broadcom/b43/phy_g.c
@@ -2297,7 +2297,7 @@ static u8 b43_gphy_aci_scan(struct b43_wldev *dev)
b43_phy_mask(dev, B43_PHY_G_CRS, 0x7FFF);
b43_set_all_gains(dev, 3, 8, 1);
- start = (channel - 5 > 0) ? channel - 5 : 1;
+ start = (channel > 5) ? channel - 5 : 1;
end = (channel + 5 < 14) ? channel + 5 : 13;
for (i = start; i <= end; i++) {
--
2.20.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH 2/2] b43: fix a lower bounds test
2021-10-06 7:36 ` [PATCH 2/2] b43: " Dan Carpenter
@ 2021-10-06 16:13 ` Michael Büsch
0 siblings, 0 replies; 5+ messages in thread
From: Michael Büsch @ 2021-10-06 16:13 UTC (permalink / raw)
To: Dan Carpenter; +Cc: Kalle Valo, kernel-janitors, linux-wireless, b43-dev
[-- Attachment #1: Type: text/plain, Size: 1455 bytes --]
On Wed, 6 Oct 2021 10:36:22 +0300
Dan Carpenter <dan.carpenter@oracle.com> wrote:
> The problem is that "channel" is an unsigned int, when it's less 5 the
> value of "channel - 5" is not a negative number as one would expect but
> is very high positive value instead.
>
> This means that "start" becomes a very high positive value. The result
> of that is that we never enter the "for (i = start; i <= end; i++) {"
> loop. Instead of storing the result from b43legacy_radio_aci_detect()
> it just uses zero.
>
> Fixes: ef1a628d83fc ("b43: Implement dynamic PHY API")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> drivers/net/wireless/broadcom/b43/phy_g.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/broadcom/b43/phy_g.c b/drivers/net/wireless/broadcom/b43/phy_g.c
> index d5a1a5c58236..ac72ca39e409 100644
> --- a/drivers/net/wireless/broadcom/b43/phy_g.c
> +++ b/drivers/net/wireless/broadcom/b43/phy_g.c
> @@ -2297,7 +2297,7 @@ static u8 b43_gphy_aci_scan(struct b43_wldev *dev)
> b43_phy_mask(dev, B43_PHY_G_CRS, 0x7FFF);
> b43_set_all_gains(dev, 3, 8, 1);
>
> - start = (channel - 5 > 0) ? channel - 5 : 1;
> + start = (channel > 5) ? channel - 5 : 1;
> end = (channel + 5 < 14) ? channel + 5 : 13;
>
> for (i = start; i <= end; i++) {
Nice finding.
Acked-by: Michael Büsch <m@bues.ch>
--
Michael
https://bues.ch/
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/2] b43legacy: fix a lower bounds test
2021-10-06 7:35 [PATCH 1/2] b43legacy: fix a lower bounds test Dan Carpenter
2021-10-06 7:36 ` [PATCH 2/2] b43: " Dan Carpenter
@ 2021-10-06 16:13 ` Michael Büsch
2021-10-11 6:09 ` Kalle Valo
2 siblings, 0 replies; 5+ messages in thread
From: Michael Büsch @ 2021-10-06 16:13 UTC (permalink / raw)
To: Dan Carpenter
Cc: Larry Finger, Kalle Valo, linux-wireless, b43-dev, kernel-janitors
[-- Attachment #1: Type: text/plain, Size: 1657 bytes --]
On Wed, 6 Oct 2021 10:35:42 +0300
Dan Carpenter <dan.carpenter@oracle.com> wrote:
> The problem is that "channel" is an unsigned int, when it's less 5 the
> value of "channel - 5" is not a negative number as one would expect but
> is very high positive value instead.
>
> This means that "start" becomes a very high positive value. The result
> of that is that we never enter the "for (i = start; i <= end; i++) {"
> loop. Instead of storing the result from b43legacy_radio_aci_detect()
> it just uses zero.
>
> Fixes: 75388acd0cd8 ("[B43LEGACY]: add mac80211-based driver for legacy BCM43xx devices")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> This fix is correct, but making dead code go live can sometimes expose
> bugs which were previously hiding and is always carries a slight risk.
>
> drivers/net/wireless/broadcom/b43legacy/radio.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/broadcom/b43legacy/radio.c b/drivers/net/wireless/broadcom/b43legacy/radio.c
> index 06891b4f837b..fdf78c10a05c 100644
> --- a/drivers/net/wireless/broadcom/b43legacy/radio.c
> +++ b/drivers/net/wireless/broadcom/b43legacy/radio.c
> @@ -283,7 +283,7 @@ u8 b43legacy_radio_aci_scan(struct b43legacy_wldev *dev)
> & 0x7FFF);
> b43legacy_set_all_gains(dev, 3, 8, 1);
>
> - start = (channel - 5 > 0) ? channel - 5 : 1;
> + start = (channel > 5) ? channel - 5 : 1;
> end = (channel + 5 < 14) ? channel + 5 : 13;
>
> for (i = start; i <= end; i++) {
Nice finding.
Acked-by: Michael Büsch <m@bues.ch>
--
Michael
https://bues.ch/
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH 1/2] b43legacy: fix a lower bounds test
2021-10-06 7:35 [PATCH 1/2] b43legacy: fix a lower bounds test Dan Carpenter
2021-10-06 7:36 ` [PATCH 2/2] b43: " Dan Carpenter
2021-10-06 16:13 ` [PATCH 1/2] b43legacy: " Michael Büsch
@ 2021-10-11 6:09 ` Kalle Valo
2 siblings, 0 replies; 5+ messages in thread
From: Kalle Valo @ 2021-10-11 6:09 UTC (permalink / raw)
To: Dan Carpenter; +Cc: Larry Finger, linux-wireless, b43-dev, kernel-janitors
Dan Carpenter <dan.carpenter@oracle.com> wrote:
> The problem is that "channel" is an unsigned int, when it's less 5 the
> value of "channel - 5" is not a negative number as one would expect but
> is very high positive value instead.
>
> This means that "start" becomes a very high positive value. The result
> of that is that we never enter the "for (i = start; i <= end; i++) {"
> loop. Instead of storing the result from b43legacy_radio_aci_detect()
> it just uses zero.
>
> Fixes: 75388acd0cd8 ("[B43LEGACY]: add mac80211-based driver for legacy BCM43xx devices")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> Acked-by: Michael Büsch <m@bues.ch>
2 patches applied to wireless-drivers-next.git, thanks.
c1c8380b0320 b43legacy: fix a lower bounds test
9b793db5fca4 b43: fix a lower bounds test
--
https://patchwork.kernel.org/project/linux-wireless/patch/20211006073542.GD8404@kili/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-10-11 6:09 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-10-06 7:35 [PATCH 1/2] b43legacy: fix a lower bounds test Dan Carpenter
2021-10-06 7:36 ` [PATCH 2/2] b43: " Dan Carpenter
2021-10-06 16:13 ` Michael Büsch
2021-10-06 16:13 ` [PATCH 1/2] b43legacy: " Michael Büsch
2021-10-11 6:09 ` Kalle Valo
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).