Re: [PATCH v1 v1] drm/nouveau: Fix memory leak in nvbios_iccsense_parse

[Danilo Krummrich <dakr@redhat.com>]

The version after the inital one should be "v2". You can use

git format-patch -v{VERSION_NUMBER} for this.

On Mon, Dec 16, 2024 at 09:03:03PM +0800, Zhanxin Qi wrote:
> The nvbios_iccsense_parse function allocates memory for sensor data
> but fails to free it when the function exits, leading to a memory
> leak. Add proper cleanup to free the allocated memory.
> 
> Fixes: 39b7e6e547ff ("drm/nouveau/nvbios/iccsense: add parsing of the SENSE table")

This should be

Fixes: b71c0892631a ("drm/nouveau/iccsense: implement for ina209, ina219 and ina3221")

instead.

The function introduced by 39b7e6e547ff ("drm/nouveau/nvbios/iccsense: add
parsing of the SENSE table") is correct, but the other commit did not clean up
after using it.

> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Zhanxin Qi <zhanxin@nfschina.com>
> Signed-off-by: Duanjun Li <duanjun@nfschina.com>

Why is there also Duanjun's SOB? If there is a co-author, this should be
indicated with a "Co-developed-by" tag. Adding the SOB only is not sufficient,
please see [1].

> Signed-off-by: Danilo Krummrich <dakr@redhat.com>

Please don't add my SOB to your commits -- I'll add it when I apply the patch.
Please also see [1].

[1] https://docs.kernel.org/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin

> ---
>  .../include/nvkm/subdev/bios/iccsense.h       |  2 ++
>  .../drm/nouveau/nvkm/subdev/bios/iccsense.c   | 20 +++++++++++++++++++
>  .../drm/nouveau/nvkm/subdev/iccsense/base.c   |  3 +++
>  3 files changed, 25 insertions(+)
> 
> diff --git a/drivers/gpu/drm/nouveau/include/nvkm/subdev/bios/iccsense.h b/drivers/gpu/drm/nouveau/include/nvkm/subdev/bios/iccsense.h
> index 4c108fd2c805..8bfc28c3f7a7 100644
> --- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/bios/iccsense.h
> +++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/bios/iccsense.h
> @@ -20,4 +20,6 @@ struct nvbios_iccsense {
>  };
>  
>  int nvbios_iccsense_parse(struct nvkm_bios *, struct nvbios_iccsense *);
> +
> +void nvbios_iccsense_cleanup(struct nvbios_iccsense *iccsense);
>  #endif
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/iccsense.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/iccsense.c
> index dea444d48f94..38fcc91ffea6 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/bios/iccsense.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bios/iccsense.c
> @@ -56,6 +56,19 @@ nvbios_iccsense_table(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *cnt,
>  	return 0;
>  }
>  
> +/**
> + * nvbios_iccsense_parse - Parse ICCSENSE table from VBIOS
> + * @bios: VBIOS base pointer
> + * @iccsense: ICCSENSE table structure to fill
> + *
> + * Parses the ICCSENSE table from VBIOS and fills the provided structure.
> + * The caller must invoke nvbios_iccsense_cleanup() after successful parsing
> + * to free the allocated rail resources.
> + *
> + * Returns:
> + *   0        - Success
> + *   -ENODEV  - Table not found
> + */

Looks good, thanks for adding this!

>  int
>  nvbios_iccsense_parse(struct nvkm_bios *bios, struct nvbios_iccsense *iccsense)
>  {
> @@ -127,3 +140,10 @@ nvbios_iccsense_parse(struct nvkm_bios *bios, struct nvbios_iccsense *iccsense)
>  
>  	return 0;
>  }
> +
> +void
> +nvbios_iccsense_cleanup(struct nvbios_iccsense *iccsense)
> +{
> +	kfree(iccsense->rail);
> +	iccsense->rail = NULL;
> +}
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c
> index 8f0ccd3664eb..4c1759ecce38 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c
> @@ -291,6 +291,9 @@ nvkm_iccsense_oneinit(struct nvkm_subdev *subdev)
>  			list_add_tail(&rail->head, &iccsense->rails);
>  		}
>  	}
> +
> +	nvbios_iccsense_cleanup(&stbl);
> +
>  	return 0;
>  }
>  
> -- 
> 2.30.2
>