diff mbox series

[v2] drm/i915: use strscpy() to avoid buffer overrun

Message ID 20210916122649.12691-1-tim.gardner@canonical.com (mailing list archive)
State New, archived
Headers show
Series [v2] drm/i915: use strscpy() to avoid buffer overrun | expand

Commit Message

Tim Gardner Sept. 16, 2021, 12:26 p.m. UTC
In capture_vma() Coverity complains of a possible buffer overrun. Even
though this is a static function where all call sites can be checked,
limiting the copy length could save some future grief.

CID 93300 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW)
4. fixed_size_dest: You might overrun the 16-character fixed-size string c->name
   by copying name without checking the length.
5. parameter_as_source: Note: This defect has an elevated risk because the
   source argument is a parameter of the current function.
1326        strcpy(c->name, name);

Fix any possible overflows by using strscpy() which guarantees NULL termination.

Also correct 2 other strcpy() call sites with the same potential for Coverity
warnings or overruns.

v2 - Change $SUBJECT from "drm/i915: zero fill vma name buffer"
     Use strscpy() instead of strncpy(). Its a much simpler change.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: intel-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
---
 drivers/gpu/drm/i915/i915_gpu_error.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Tvrtko Ursulin Sept. 17, 2021, 7:37 a.m. UTC | #1
On 16/09/2021 13:26, Tim Gardner wrote:
> In capture_vma() Coverity complains of a possible buffer overrun. Even
> though this is a static function where all call sites can be checked,
> limiting the copy length could save some future grief.
> 
> CID 93300 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW)
> 4. fixed_size_dest: You might overrun the 16-character fixed-size string c->name
>     by copying name without checking the length.
> 5. parameter_as_source: Note: This defect has an elevated risk because the
>     source argument is a parameter of the current function.
> 1326        strcpy(c->name, name);
> 
> Fix any possible overflows by using strscpy() which guarantees NULL termination.
> 
> Also correct 2 other strcpy() call sites with the same potential for Coverity
> warnings or overruns.
> 
> v2 - Change $SUBJECT from "drm/i915: zero fill vma name buffer"
>       Use strscpy() instead of strncpy(). Its a much simpler change.
> 
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: intel-gfx@lists.freedesktop.org
> Cc: dri-devel@lists.freedesktop.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
> ---
>   drivers/gpu/drm/i915/i915_gpu_error.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
> index 9cf6ac575de1..7f246f51959d 100644
> --- a/drivers/gpu/drm/i915/i915_gpu_error.c
> +++ b/drivers/gpu/drm/i915/i915_gpu_error.c
> @@ -1015,7 +1015,7 @@ i915_vma_coredump_create(const struct intel_gt *gt,
>   		return NULL;
>   	}
>   
> -	strcpy(dst->name, name);
> +	strscpy(dst->name, name, sizeof(dst->name));
>   	dst->next = NULL;
>   
>   	dst->gtt_offset = vma->node.start;
> @@ -1279,7 +1279,7 @@ static bool record_context(struct i915_gem_context_coredump *e,
>   	rcu_read_lock();
>   	task = pid_task(ctx->pid, PIDTYPE_PID);
>   	if (task) {
> -		strcpy(e->comm, task->comm);
> +		strscpy(e->comm, task->comm, sizeof(e->comm));
>   		e->pid = task->pid;
>   	}
>   	rcu_read_unlock();
> @@ -1323,7 +1323,7 @@ capture_vma(struct intel_engine_capture_vma *next,
>   		return next;
>   	}
>   
> -	strcpy(c->name, name);
> +	strscpy(c->name, name, sizeof(c->name));
>   	c->vma = vma; /* reference held while active */
>   
>   	c->next = next;
> 

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 9cf6ac575de1..7f246f51959d 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1015,7 +1015,7 @@  i915_vma_coredump_create(const struct intel_gt *gt,
 		return NULL;
 	}
 
-	strcpy(dst->name, name);
+	strscpy(dst->name, name, sizeof(dst->name));
 	dst->next = NULL;
 
 	dst->gtt_offset = vma->node.start;
@@ -1279,7 +1279,7 @@  static bool record_context(struct i915_gem_context_coredump *e,
 	rcu_read_lock();
 	task = pid_task(ctx->pid, PIDTYPE_PID);
 	if (task) {
-		strcpy(e->comm, task->comm);
+		strscpy(e->comm, task->comm, sizeof(e->comm));
 		e->pid = task->pid;
 	}
 	rcu_read_unlock();
@@ -1323,7 +1323,7 @@  capture_vma(struct intel_engine_capture_vma *next,
 		return next;
 	}
 
-	strcpy(c->name, name);
+	strscpy(c->name, name, sizeof(c->name));
 	c->vma = vma; /* reference held while active */
 
 	c->next = next;