* [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
@ 2021-01-21 10:52 Dongliang Mu
2021-01-21 11:19 ` Greg KH
0 siblings, 1 reply; 8+ messages in thread
From: Dongliang Mu @ 2021-01-21 10:52 UTC (permalink / raw)
To: davem, helmut.schaa, kvalo, gregkh
Cc: linux-kernel, linux-wireless, netdev, sgruszka, Dongliang Mu
In the function rt2500usb_register_read(_lock), reg is uninitialized
in some situation. Then KMSAN reports uninit-value at its first memory
access. To fix this issue, initialize reg with zero in the function
rt2500usb_register_read and rt2500usb_register_read_lock
BUG: KMSAN: uninit-value in rt2500usb_init_eeprom rt2500usb.c:1443 [inline]
BUG: KMSAN: uninit-value in rt2500usb_probe_hw+0xb5e/0x22a0 rt2500usb.c:1757
CPU: 0 PID: 3369 Comm: kworker/0:2 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Compute Engine
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x191/0x1f0 lib/dump_stack.c:113
kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
__msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1443 [inline]
rt2500usb_probe_hw+0xb5e/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
rt2x00usb_probe+0x7ae/0xf60 wireless/ralink/rt2x00/rt2x00usb.c:842
rt2500usb_probe+0x50/0x60 wireless/ralink/rt2x00/rt2500usb.c:1966
......
Local variable description: ----reg.i.i@rt2500usb_probe_hw
Variable was created at:
rt2500usb_register_read wireless/ralink/rt2x00/rt2500usb.c:51 [inline]
rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1440 [inline]
rt2500usb_probe_hw+0x774/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
---
drivers/net/wireless/ralink/rt2x00/rt2500usb.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
index fce05fc88aaf..98567dc96415 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
@@ -47,7 +47,7 @@ MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");
static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
const unsigned int offset)
{
- __le16 reg;
+ __le16 reg = 0;
rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
USB_VENDOR_REQUEST_IN, offset,
®, sizeof(reg));
@@ -57,7 +57,7 @@ static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
static u16 rt2500usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
const unsigned int offset)
{
- __le16 reg;
+ __le16 reg = 0;
rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
USB_VENDOR_REQUEST_IN, offset,
®, sizeof(reg), REGISTER_TIMEOUT);
--
2.25.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
2021-01-21 10:52 [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read Dongliang Mu
@ 2021-01-21 11:19 ` Greg KH
0 siblings, 0 replies; 8+ messages in thread
From: Greg KH @ 2021-01-21 11:19 UTC (permalink / raw)
To: Dongliang Mu
Cc: davem, helmut.schaa, kvalo, linux-kernel, linux-wireless, netdev,
sgruszka
On Thu, Jan 21, 2021 at 06:52:46PM +0800, Dongliang Mu wrote:
> In the function rt2500usb_register_read(_lock), reg is uninitialized
> in some situation. Then KMSAN reports uninit-value at its first memory
> access. To fix this issue, initialize reg with zero in the function
> rt2500usb_register_read and rt2500usb_register_read_lock
>
> BUG: KMSAN: uninit-value in rt2500usb_init_eeprom rt2500usb.c:1443 [inline]
> BUG: KMSAN: uninit-value in rt2500usb_probe_hw+0xb5e/0x22a0 rt2500usb.c:1757
> CPU: 0 PID: 3369 Comm: kworker/0:2 Not tainted 5.3.0-rc7+ #0
> Hardware name: Google Compute Engine
> Workqueue: usb_hub_wq hub_event
> Call Trace:
> __dump_stack lib/dump_stack.c:77 [inline]
> dump_stack+0x191/0x1f0 lib/dump_stack.c:113
> kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
> __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
> rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1443 [inline]
> rt2500usb_probe_hw+0xb5e/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
> rt2x00usb_probe+0x7ae/0xf60 wireless/ralink/rt2x00/rt2x00usb.c:842
> rt2500usb_probe+0x50/0x60 wireless/ralink/rt2x00/rt2500usb.c:1966
> ......
>
> Local variable description: ----reg.i.i@rt2500usb_probe_hw
> Variable was created at:
> rt2500usb_register_read wireless/ralink/rt2x00/rt2500usb.c:51 [inline]
> rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1440 [inline]
> rt2500usb_probe_hw+0x774/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
>
> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> ---
> drivers/net/wireless/ralink/rt2x00/rt2500usb.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> index fce05fc88aaf..98567dc96415 100644
> --- a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> +++ b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> @@ -47,7 +47,7 @@ MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");
> static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
> const unsigned int offset)
> {
> - __le16 reg;
> + __le16 reg = 0;
> rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
> USB_VENDOR_REQUEST_IN, offset,
> ®, sizeof(reg));
> @@ -57,7 +57,7 @@ static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
> static u16 rt2500usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
> const unsigned int offset)
> {
> - __le16 reg;
> + __le16 reg = 0;
> rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
> USB_VENDOR_REQUEST_IN, offset,
> ®, sizeof(reg), REGISTER_TIMEOUT);
> --
> 2.25.1
>
Hi,
This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
a patch that has triggered this response. He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created. Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.
You are receiving this message because of the following common error(s)
as indicated below:
- This looks like a new version of a previously submitted patch, but you
did not list below the --- line any changes from the previous version.
Please read the section entitled "The canonical patch format" in the
kernel file, Documentation/SubmittingPatches for what needs to be done
here to properly describe this.
If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.
thanks,
greg k-h's patch email bot
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
2021-01-21 11:21 ` Greg KH
@ 2021-01-21 11:25 ` 慕冬亮
0 siblings, 0 replies; 8+ messages in thread
From: 慕冬亮 @ 2021-01-21 11:25 UTC (permalink / raw)
To: Greg KH
Cc: davem, helmut.schaa, kvalo, linux-kernel, linux-wireless, netdev,
sgruszka
On Thu, Jan 21, 2021 at 7:21 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Thu, Jan 21, 2021 at 06:59:08PM +0800, 慕冬亮 wrote:
> > > > rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
> > > > USB_VENDOR_REQUEST_IN, offset,
> > > > ®, sizeof(reg));
> > >
> > > Are you sure this is valid to call this function with a variable on the
> > > stack like this? How did you test this change?
> >
> > First, I did not do any changes to this call. Second, the programming
> > style to pass the pointer of stack variable as arguments is not really
> > good. Third, I check this same code file, there are many code snippets
> > with such programming style. :(
>
> I know you did not change it, what I am asking is how did you test this
> change works? I think the kernel will warn you in huge ways that using
> this pointer on the stack is incorrect, which implies you did not test
> this change :(
>
I tested this patch only with PoC. The patched kernel version did not
crash when executing the PoC.
BTW, I did not take notice of the warning information as there are
many many warnings in building KMSAN.
> thanks,
>
> greg k-h
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
2021-01-21 10:59 ` 慕冬亮
2021-01-21 11:20 ` Greg KH
@ 2021-01-21 11:21 ` Greg KH
2021-01-21 11:25 ` 慕冬亮
1 sibling, 1 reply; 8+ messages in thread
From: Greg KH @ 2021-01-21 11:21 UTC (permalink / raw)
To: 慕冬亮
Cc: davem, helmut.schaa, kvalo, linux-kernel, linux-wireless, netdev,
sgruszka
On Thu, Jan 21, 2021 at 06:59:08PM +0800, 慕冬亮 wrote:
> > > rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
> > > USB_VENDOR_REQUEST_IN, offset,
> > > ®, sizeof(reg));
> >
> > Are you sure this is valid to call this function with a variable on the
> > stack like this? How did you test this change?
>
> First, I did not do any changes to this call. Second, the programming
> style to pass the pointer of stack variable as arguments is not really
> good. Third, I check this same code file, there are many code snippets
> with such programming style. :(
I know you did not change it, what I am asking is how did you test this
change works? I think the kernel will warn you in huge ways that using
this pointer on the stack is incorrect, which implies you did not test
this change :(
thanks,
greg k-h
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
2021-01-21 10:59 ` 慕冬亮
@ 2021-01-21 11:20 ` Greg KH
2021-01-21 11:21 ` Greg KH
1 sibling, 0 replies; 8+ messages in thread
From: Greg KH @ 2021-01-21 11:20 UTC (permalink / raw)
To: 慕冬亮
Cc: davem, helmut.schaa, kvalo, linux-kernel, linux-wireless, netdev,
sgruszka
On Thu, Jan 21, 2021 at 06:59:08PM +0800, 慕冬亮 wrote:
> On Thu, Jan 21, 2021 at 5:49 PM Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > On Thu, Jan 21, 2021 at 05:20:26PM +0800, Dongliang Mu wrote:
> > > In the function rt2500usb_register_read(_lock), reg is uninitialized
> > > in some situation. Then KMSAN reports uninit-value at its first memory
> > > access. To fix this issue, add one reg initialization in the function
> > > rt2500usb_register_read and rt2500usb_register_read_lock
> > >
> > > BUG: KMSAN: uninit-value in rt2500usb_init_eeprom rt2500usb.c:1443 [inline]
> > > BUG: KMSAN: uninit-value in rt2500usb_probe_hw+0xb5e/0x22a0 rt2500usb.c:1757
> > > CPU: 0 PID: 3369 Comm: kworker/0:2 Not tainted 5.3.0-rc7+ #0
> > > Hardware name: Google Compute Engine
> > > Workqueue: usb_hub_wq hub_event
> > > Call Trace:
> > > __dump_stack lib/dump_stack.c:77 [inline]
> > > dump_stack+0x191/0x1f0 lib/dump_stack.c:113
> > > kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
> > > __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
> > > rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1443 [inline]
> > > rt2500usb_probe_hw+0xb5e/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> > > rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
> > > rt2x00usb_probe+0x7ae/0xf60 wireless/ralink/rt2x00/rt2x00usb.c:842
> > > rt2500usb_probe+0x50/0x60 wireless/ralink/rt2x00/rt2500usb.c:1966
> > > ......
> > >
> > > Local variable description: ----reg.i.i@rt2500usb_probe_hw
> > > Variable was created at:
> > > rt2500usb_register_read wireless/ralink/rt2x00/rt2500usb.c:51 [inline]
> > > rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1440 [inline]
> > > rt2500usb_probe_hw+0x774/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> > > rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
> > >
> > > Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> > > ---
> > > drivers/net/wireless/ralink/rt2x00/rt2500usb.c | 2 ++
> > > 1 file changed, 2 insertions(+)
> > >
> > > diff --git a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> > > index fce05fc88aaf..f6c93a25b18c 100644
> > > --- a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> > > +++ b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> > > @@ -48,6 +48,7 @@ static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
> > > const unsigned int offset)
> > > {
> > > __le16 reg;
> > > + memset(®, 0, sizeof(reg));
> >
> > As was pointed out, just set reg = 0 on the line above please.
>
> I've sent another patch.
>
> BTW, I set "--subject-prefix="PATCH v2" in my git-send-mail command.
> But it does not show "v2" in the subject of the new email.
You can set the "v2" in the 'git format-patch' option, right?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
2021-01-21 9:49 ` Greg KH
@ 2021-01-21 10:59 ` 慕冬亮
2021-01-21 11:20 ` Greg KH
2021-01-21 11:21 ` Greg KH
0 siblings, 2 replies; 8+ messages in thread
From: 慕冬亮 @ 2021-01-21 10:59 UTC (permalink / raw)
To: Greg KH
Cc: davem, helmut.schaa, kvalo, linux-kernel, linux-wireless, netdev,
sgruszka
On Thu, Jan 21, 2021 at 5:49 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Thu, Jan 21, 2021 at 05:20:26PM +0800, Dongliang Mu wrote:
> > In the function rt2500usb_register_read(_lock), reg is uninitialized
> > in some situation. Then KMSAN reports uninit-value at its first memory
> > access. To fix this issue, add one reg initialization in the function
> > rt2500usb_register_read and rt2500usb_register_read_lock
> >
> > BUG: KMSAN: uninit-value in rt2500usb_init_eeprom rt2500usb.c:1443 [inline]
> > BUG: KMSAN: uninit-value in rt2500usb_probe_hw+0xb5e/0x22a0 rt2500usb.c:1757
> > CPU: 0 PID: 3369 Comm: kworker/0:2 Not tainted 5.3.0-rc7+ #0
> > Hardware name: Google Compute Engine
> > Workqueue: usb_hub_wq hub_event
> > Call Trace:
> > __dump_stack lib/dump_stack.c:77 [inline]
> > dump_stack+0x191/0x1f0 lib/dump_stack.c:113
> > kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
> > __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
> > rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1443 [inline]
> > rt2500usb_probe_hw+0xb5e/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> > rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
> > rt2x00usb_probe+0x7ae/0xf60 wireless/ralink/rt2x00/rt2x00usb.c:842
> > rt2500usb_probe+0x50/0x60 wireless/ralink/rt2x00/rt2500usb.c:1966
> > ......
> >
> > Local variable description: ----reg.i.i@rt2500usb_probe_hw
> > Variable was created at:
> > rt2500usb_register_read wireless/ralink/rt2x00/rt2500usb.c:51 [inline]
> > rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1440 [inline]
> > rt2500usb_probe_hw+0x774/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> > rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
> >
> > Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> > ---
> > drivers/net/wireless/ralink/rt2x00/rt2500usb.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> > index fce05fc88aaf..f6c93a25b18c 100644
> > --- a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> > +++ b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> > @@ -48,6 +48,7 @@ static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
> > const unsigned int offset)
> > {
> > __le16 reg;
> > + memset(®, 0, sizeof(reg));
>
> As was pointed out, just set reg = 0 on the line above please.
I've sent another patch.
BTW, I set "--subject-prefix="PATCH v2" in my git-send-mail command.
But it does not show "v2" in the subject of the new email.
>
> > rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
> > USB_VENDOR_REQUEST_IN, offset,
> > ®, sizeof(reg));
>
> Are you sure this is valid to call this function with a variable on the
> stack like this? How did you test this change?
First, I did not do any changes to this call. Second, the programming
style to pass the pointer of stack variable as arguments is not really
good. Third, I check this same code file, there are many code snippets
with such programming style. :(
>
> thanks,
>
> greg k-h
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
2021-01-21 9:20 Dongliang Mu
@ 2021-01-21 9:49 ` Greg KH
2021-01-21 10:59 ` 慕冬亮
0 siblings, 1 reply; 8+ messages in thread
From: Greg KH @ 2021-01-21 9:49 UTC (permalink / raw)
To: Dongliang Mu
Cc: davem, helmut.schaa, kvalo, linux-kernel, linux-wireless, netdev,
sgruszka
On Thu, Jan 21, 2021 at 05:20:26PM +0800, Dongliang Mu wrote:
> In the function rt2500usb_register_read(_lock), reg is uninitialized
> in some situation. Then KMSAN reports uninit-value at its first memory
> access. To fix this issue, add one reg initialization in the function
> rt2500usb_register_read and rt2500usb_register_read_lock
>
> BUG: KMSAN: uninit-value in rt2500usb_init_eeprom rt2500usb.c:1443 [inline]
> BUG: KMSAN: uninit-value in rt2500usb_probe_hw+0xb5e/0x22a0 rt2500usb.c:1757
> CPU: 0 PID: 3369 Comm: kworker/0:2 Not tainted 5.3.0-rc7+ #0
> Hardware name: Google Compute Engine
> Workqueue: usb_hub_wq hub_event
> Call Trace:
> __dump_stack lib/dump_stack.c:77 [inline]
> dump_stack+0x191/0x1f0 lib/dump_stack.c:113
> kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
> __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
> rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1443 [inline]
> rt2500usb_probe_hw+0xb5e/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
> rt2x00usb_probe+0x7ae/0xf60 wireless/ralink/rt2x00/rt2x00usb.c:842
> rt2500usb_probe+0x50/0x60 wireless/ralink/rt2x00/rt2500usb.c:1966
> ......
>
> Local variable description: ----reg.i.i@rt2500usb_probe_hw
> Variable was created at:
> rt2500usb_register_read wireless/ralink/rt2x00/rt2500usb.c:51 [inline]
> rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1440 [inline]
> rt2500usb_probe_hw+0x774/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
> rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
>
> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> ---
> drivers/net/wireless/ralink/rt2x00/rt2500usb.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> index fce05fc88aaf..f6c93a25b18c 100644
> --- a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> +++ b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
> @@ -48,6 +48,7 @@ static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
> const unsigned int offset)
> {
> __le16 reg;
> + memset(®, 0, sizeof(reg));
As was pointed out, just set reg = 0 on the line above please.
> rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
> USB_VENDOR_REQUEST_IN, offset,
> ®, sizeof(reg));
Are you sure this is valid to call this function with a variable on the
stack like this? How did you test this change?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read
@ 2021-01-21 9:20 Dongliang Mu
2021-01-21 9:49 ` Greg KH
0 siblings, 1 reply; 8+ messages in thread
From: Dongliang Mu @ 2021-01-21 9:20 UTC (permalink / raw)
To: davem, helmut.schaa, kvalo, gregkh
Cc: linux-kernel, linux-wireless, netdev, sgruszka, Dongliang Mu
In the function rt2500usb_register_read(_lock), reg is uninitialized
in some situation. Then KMSAN reports uninit-value at its first memory
access. To fix this issue, add one reg initialization in the function
rt2500usb_register_read and rt2500usb_register_read_lock
BUG: KMSAN: uninit-value in rt2500usb_init_eeprom rt2500usb.c:1443 [inline]
BUG: KMSAN: uninit-value in rt2500usb_probe_hw+0xb5e/0x22a0 rt2500usb.c:1757
CPU: 0 PID: 3369 Comm: kworker/0:2 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Compute Engine
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x191/0x1f0 lib/dump_stack.c:113
kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
__msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1443 [inline]
rt2500usb_probe_hw+0xb5e/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
rt2x00usb_probe+0x7ae/0xf60 wireless/ralink/rt2x00/rt2x00usb.c:842
rt2500usb_probe+0x50/0x60 wireless/ralink/rt2x00/rt2500usb.c:1966
......
Local variable description: ----reg.i.i@rt2500usb_probe_hw
Variable was created at:
rt2500usb_register_read wireless/ralink/rt2x00/rt2500usb.c:51 [inline]
rt2500usb_init_eeprom wireless/ralink/rt2x00/rt2500usb.c:1440 [inline]
rt2500usb_probe_hw+0x774/0x22a0 wireless/ralink/rt2x00/rt2500usb.c:1757
rt2x00lib_probe_dev+0xba9/0x3260 wireless/ralink/rt2x00/rt2x00dev.c:1427
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
---
drivers/net/wireless/ralink/rt2x00/rt2500usb.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
index fce05fc88aaf..f6c93a25b18c 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2500usb.c
@@ -48,6 +48,7 @@ static u16 rt2500usb_register_read(struct rt2x00_dev *rt2x00dev,
const unsigned int offset)
{
__le16 reg;
+ memset(®, 0, sizeof(reg));
rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
USB_VENDOR_REQUEST_IN, offset,
®, sizeof(reg));
@@ -58,6 +59,7 @@ static u16 rt2500usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
const unsigned int offset)
{
__le16 reg;
+ memset(®, 0, sizeof(reg));
rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
USB_VENDOR_REQUEST_IN, offset,
®, sizeof(reg), REGISTER_TIMEOUT);
--
2.25.1
^ permalink raw reply related [flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-01-21 11:59 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-21 10:52 [PATCH] rt2x00: reset reg earlier in rt2500usb_register_read Dongliang Mu
2021-01-21 11:19 ` Greg KH
-- strict thread matches above, loose matches on Subject: below --
2021-01-21 9:20 Dongliang Mu
2021-01-21 9:49 ` Greg KH
2021-01-21 10:59 ` 慕冬亮
2021-01-21 11:20 ` Greg KH
2021-01-21 11:21 ` Greg KH
2021-01-21 11:25 ` 慕冬亮
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