dma-buf: st: fix error handling in test_get_fences()

Message ID 20211026083448.3471055-1-arnd@kernel.org (mailing list archive)
State Not Applicable, archived
Headers
Series dma-buf: st: fix error handling in test_get_fences() |

Commit Message

Arnd Bergmann Oct. 26, 2021, 8:34 a.m. UTC
  From: Arnd Bergmann <arnd@arndb.de>

The new driver incorrectly unwinds after errors, as clang points out:

drivers/dma-buf/st-dma-resv.c:295:7: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
                if (r) {
                    ^
drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
        while (i--)
               ^
drivers/dma-buf/st-dma-resv.c:295:3: note: remove the 'if' if its condition is always false
                if (r) {
                ^~~~~~~~
drivers/dma-buf/st-dma-resv.c:288:6: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
        if (r) {
            ^
drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
        while (i--)
               ^
drivers/dma-buf/st-dma-resv.c:288:2: note: remove the 'if' if its condition is always false
        if (r) {
        ^~~~~~~~
drivers/dma-buf/st-dma-resv.c:280:10: note: initialize the variable 'i' to silence this warning
        int r, i;
                ^
                 = 0

Skip cleaning up the bits that have not been allocated at this point.

Fixes: 1d51775cd3f5 ("dma-buf: add dma_resv selftest v4")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
I'm not familiar with these interfaces, so I'm just guessing where
we should jump after an error, please double-check and fix if necessary.
---
 drivers/dma-buf/st-dma-resv.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
  

Comments

Christian König Oct. 26, 2021, 10:55 a.m. UTC | #1
Am 26.10.21 um 10:34 schrieb Arnd Bergmann:
> From: Arnd Bergmann <arnd@arndb.de>
>
> The new driver incorrectly unwinds after errors, as clang points out:
>
> drivers/dma-buf/st-dma-resv.c:295:7: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>                  if (r) {
>                      ^
> drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
>          while (i--)
>                 ^
> drivers/dma-buf/st-dma-resv.c:295:3: note: remove the 'if' if its condition is always false
>                  if (r) {
>                  ^~~~~~~~
> drivers/dma-buf/st-dma-resv.c:288:6: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>          if (r) {
>              ^
> drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
>          while (i--)
>                 ^
> drivers/dma-buf/st-dma-resv.c:288:2: note: remove the 'if' if its condition is always false
>          if (r) {
>          ^~~~~~~~
> drivers/dma-buf/st-dma-resv.c:280:10: note: initialize the variable 'i' to silence this warning
>          int r, i;
>                  ^
>                   = 0
>
> Skip cleaning up the bits that have not been allocated at this point.
>
> Fixes: 1d51775cd3f5 ("dma-buf: add dma_resv selftest v4")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

I already send out a patch to fix this up, but forgot to fix both gotos.

Going to add my rb and using that one here instead.

Thanks,
Christian.

> ---
> I'm not familiar with these interfaces, so I'm just guessing where
> we should jump after an error, please double-check and fix if necessary.
> ---
>   drivers/dma-buf/st-dma-resv.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma-buf/st-dma-resv.c b/drivers/dma-buf/st-dma-resv.c
> index 6f3ba756da3e..bc32b3eedcb6 100644
> --- a/drivers/dma-buf/st-dma-resv.c
> +++ b/drivers/dma-buf/st-dma-resv.c
> @@ -287,7 +287,7 @@ static int test_get_fences(void *arg, bool shared)
>   	r = dma_resv_lock(&resv, NULL);
>   	if (r) {
>   		pr_err("Resv locking failed\n");
> -		goto err_free;
> +		goto err_resv;
>   	}
>   
>   	if (shared) {
> @@ -295,7 +295,7 @@ static int test_get_fences(void *arg, bool shared)
>   		if (r) {
>   			pr_err("Resv shared slot allocation failed\n");
>   			dma_resv_unlock(&resv);
> -			goto err_free;
> +			goto err_resv;
>   		}
>   
>   		dma_resv_add_shared_fence(&resv, f);
> @@ -336,6 +336,7 @@ static int test_get_fences(void *arg, bool shared)
>   	while (i--)
>   		dma_fence_put(fences[i]);
>   	kfree(fences);
> +err_resv:
>   	dma_resv_fini(&resv);
>   	dma_fence_put(f);
>   	return r;
  
Nathan Chancellor Oct. 26, 2021, 2:04 p.m. UTC | #2
On Tue, Oct 26, 2021 at 10:34:37AM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The new driver incorrectly unwinds after errors, as clang points out:
> 
> drivers/dma-buf/st-dma-resv.c:295:7: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>                 if (r) {
>                     ^
> drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
>         while (i--)
>                ^
> drivers/dma-buf/st-dma-resv.c:295:3: note: remove the 'if' if its condition is always false
>                 if (r) {
>                 ^~~~~~~~
> drivers/dma-buf/st-dma-resv.c:288:6: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>         if (r) {
>             ^
> drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
>         while (i--)
>                ^
> drivers/dma-buf/st-dma-resv.c:288:2: note: remove the 'if' if its condition is always false
>         if (r) {
>         ^~~~~~~~
> drivers/dma-buf/st-dma-resv.c:280:10: note: initialize the variable 'i' to silence this warning
>         int r, i;
>                 ^
>                  = 0
> 
> Skip cleaning up the bits that have not been allocated at this point.
> 
> Fixes: 1d51775cd3f5 ("dma-buf: add dma_resv selftest v4")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Reviewed-by: Nathan Chancellor <nathan@kernel.org>

> ---
> I'm not familiar with these interfaces, so I'm just guessing where
> we should jump after an error, please double-check and fix if necessary.
> ---
>  drivers/dma-buf/st-dma-resv.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/dma-buf/st-dma-resv.c b/drivers/dma-buf/st-dma-resv.c
> index 6f3ba756da3e..bc32b3eedcb6 100644
> --- a/drivers/dma-buf/st-dma-resv.c
> +++ b/drivers/dma-buf/st-dma-resv.c
> @@ -287,7 +287,7 @@ static int test_get_fences(void *arg, bool shared)
>  	r = dma_resv_lock(&resv, NULL);
>  	if (r) {
>  		pr_err("Resv locking failed\n");
> -		goto err_free;
> +		goto err_resv;
>  	}
>  
>  	if (shared) {
> @@ -295,7 +295,7 @@ static int test_get_fences(void *arg, bool shared)
>  		if (r) {
>  			pr_err("Resv shared slot allocation failed\n");
>  			dma_resv_unlock(&resv);
> -			goto err_free;
> +			goto err_resv;
>  		}
>  
>  		dma_resv_add_shared_fence(&resv, f);
> @@ -336,6 +336,7 @@ static int test_get_fences(void *arg, bool shared)
>  	while (i--)
>  		dma_fence_put(fences[i]);
>  	kfree(fences);
> +err_resv:
>  	dma_resv_fini(&resv);
>  	dma_fence_put(f);
>  	return r;
> -- 
> 2.29.2
>
  

Patch

diff --git a/drivers/dma-buf/st-dma-resv.c b/drivers/dma-buf/st-dma-resv.c
index 6f3ba756da3e..bc32b3eedcb6 100644
--- a/drivers/dma-buf/st-dma-resv.c
+++ b/drivers/dma-buf/st-dma-resv.c
@@ -287,7 +287,7 @@  static int test_get_fences(void *arg, bool shared)
 	r = dma_resv_lock(&resv, NULL);
 	if (r) {
 		pr_err("Resv locking failed\n");
-		goto err_free;
+		goto err_resv;
 	}
 
 	if (shared) {
@@ -295,7 +295,7 @@  static int test_get_fences(void *arg, bool shared)
 		if (r) {
 			pr_err("Resv shared slot allocation failed\n");
 			dma_resv_unlock(&resv);
-			goto err_free;
+			goto err_resv;
 		}
 
 		dma_resv_add_shared_fence(&resv, f);
@@ -336,6 +336,7 @@  static int test_get_fences(void *arg, bool shared)
 	while (i--)
 		dma_fence_put(fences[i]);
 	kfree(fences);
+err_resv:
 	dma_resv_fini(&resv);
 	dma_fence_put(f);
 	return r;