* [PATCH][next] drm/amdgpu: fix return of an uninitialized value in variable ret
@ 2019-05-10 10:08 Colin King
2019-05-10 11:16 ` Dan Carpenter
2019-05-11 1:37 ` Nathan Chancellor
0 siblings, 2 replies; 3+ messages in thread
From: Colin King @ 2019-05-10 10:08 UTC (permalink / raw)
To: Alex Deucher, Christian König, David Zhou, David Airlie,
Daniel Vetter, amd-gfx, dri-devel
Cc: kernel-janitors, linux-kernel
From: Colin Ian King <colin.king@canonical.com>
In the case where is_enable is false and lo_base_addr is non-zero the
variable ret has not been initialized and is being checked for non-zero
and potentially garbage is being returned. Fix this by not returning
ret but instead returning -EINVAL on the zero lo_base_addr case.
Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: a6ac0b44bab9 ("drm/amdgpu: add df perfmon regs and funcs for xgmi")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
drivers/gpu/drm/amd/amdgpu/df_v3_6.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/df_v3_6.c b/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
index a5c3558869fb..8c09bf994acd 100644
--- a/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
+++ b/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
@@ -398,10 +398,7 @@ static int df_v3_6_start_xgmi_link_cntr(struct amdgpu_device *adev,
NULL);
if (lo_base_addr == 0)
- ret = -EINVAL;
-
- if (ret)
- return ret;
+ return -EINVAL;
lo_val = RREG32_PCIE(lo_base_addr);
--
2.20.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH][next] drm/amdgpu: fix return of an uninitialized value in variable ret
2019-05-10 10:08 [PATCH][next] drm/amdgpu: fix return of an uninitialized value in variable ret Colin King
@ 2019-05-10 11:16 ` Dan Carpenter
2019-05-11 1:37 ` Nathan Chancellor
1 sibling, 0 replies; 3+ messages in thread
From: Dan Carpenter @ 2019-05-10 11:16 UTC (permalink / raw)
To: Colin King
Cc: Alex Deucher, Christian König, David Zhou, David Airlie,
Daniel Vetter, amd-gfx, dri-devel, kernel-janitors, linux-kernel
On Fri, May 10, 2019 at 11:08:42AM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
>
> In the case where is_enable is false and lo_base_addr is non-zero the
> variable ret has not been initialized and is being checked for non-zero
> and potentially garbage is being returned. Fix this by not returning
> ret but instead returning -EINVAL on the zero lo_base_addr case.
>
> Addresses-Coverity: ("Uninitialized scalar variable")
> Fixes: a6ac0b44bab9 ("drm/amdgpu: add df perfmon regs and funcs for xgmi")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
> drivers/gpu/drm/amd/amdgpu/df_v3_6.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/df_v3_6.c b/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
> index a5c3558869fb..8c09bf994acd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
> +++ b/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
> @@ -398,10 +398,7 @@ static int df_v3_6_start_xgmi_link_cntr(struct amdgpu_device *adev,
> NULL);
>
> if (lo_base_addr == 0)
> - ret = -EINVAL;
> -
> - if (ret)
> - return ret;
> + return -EINVAL;
From a naive reading of the code without knowing the hardware spec then
you would probably think that lo_base_addr can also be uninitialized.
<sad face emoji>
regards,
dan carpenter
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH][next] drm/amdgpu: fix return of an uninitialized value in variable ret
2019-05-10 10:08 [PATCH][next] drm/amdgpu: fix return of an uninitialized value in variable ret Colin King
2019-05-10 11:16 ` Dan Carpenter
@ 2019-05-11 1:37 ` Nathan Chancellor
1 sibling, 0 replies; 3+ messages in thread
From: Nathan Chancellor @ 2019-05-11 1:37 UTC (permalink / raw)
To: Colin King
Cc: Alex Deucher, Christian König, David Zhou, David Airlie,
Daniel Vetter, amd-gfx, dri-devel, kernel-janitors, linux-kernel
On Fri, May 10, 2019 at 11:08:42AM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
>
> In the case where is_enable is false and lo_base_addr is non-zero the
> variable ret has not been initialized and is being checked for non-zero
> and potentially garbage is being returned. Fix this by not returning
> ret but instead returning -EINVAL on the zero lo_base_addr case.
>
> Addresses-Coverity: ("Uninitialized scalar variable")
> Fixes: a6ac0b44bab9 ("drm/amdgpu: add df perfmon regs and funcs for xgmi")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
This fixes a clang warning complaining about the same thing.
> ---
> drivers/gpu/drm/amd/amdgpu/df_v3_6.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/df_v3_6.c b/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
> index a5c3558869fb..8c09bf994acd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
> +++ b/drivers/gpu/drm/amd/amdgpu/df_v3_6.c
> @@ -398,10 +398,7 @@ static int df_v3_6_start_xgmi_link_cntr(struct amdgpu_device *adev,
> NULL);
>
> if (lo_base_addr == 0)
> - ret = -EINVAL;
> -
> - if (ret)
> - return ret;
> + return -EINVAL;
>
> lo_val = RREG32_PCIE(lo_base_addr);
>
> --
> 2.20.1
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-05-11 1:37 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-05-10 10:08 [PATCH][next] drm/amdgpu: fix return of an uninitialized value in variable ret Colin King
2019-05-10 11:16 ` Dan Carpenter
2019-05-11 1:37 ` Nathan Chancellor
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).