[PATCH v2 0/3] boot: android: rework the bootargs concatenation

[PATCH v2 0/3] boot: android: rework the bootargs concatenation

[Nicolas Belin]

Rework the bootargs concatenation logic to make the logic clearer
and address several issues such as:
- checking the value at the address kcmdline_extra instead of
checking the address value itself
- freeing the string that was malloced for the concatenation
- making sure to malloc the right amount of bytes for the concatenated
string, not forgetting the byte for the NULL termination 

Signed-off-by: Nicolas Belin <nbelin@baylibre.com>
---
Changes in v2:
- Improve the logic to avoid trailing whitespaces in the concatenated
  bootargs
- Drop the last patch reordering the length calculation as it is already
  done by the improved logic
- Link to v1: https://lore.kernel.org/r/20241211-fix-bootargs-concatenation-v1-0-c6752bcb9dde@baylibre.com

---
Nicolas Belin (3):
      boot: android: fix extra command line support
      boot: android: free newbootargs when done
      boot: android: rework bootargs concatenation

 boot/image-android.c | 34 +++++++++++++++++++---------------
 1 file changed, 19 insertions(+), 15 deletions(-)
---
base-commit: b841e559cd26ffcb20f22e8ee75debed9616c002
change-id: 20241211-fix-bootargs-concatenation-8b616c110b63

Best regards,
-- 
Nicolas Belin <nbelin@baylibre.com>

[PATCH v2 1/3] boot: android: fix extra command line support

[Nicolas Belin]

Check that the value at the address kcmdline_extra is not 0
instead of checking the address value itself keeping it
consistent with what is done for kcmdline.

Fixes: b36b227b ("android: boot: support extra command line")
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Signed-off-by: Nicolas Belin <nbelin@baylibre.com>
---
 boot/image-android.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/boot/image-android.c b/boot/image-android.c
index cd01278f211d63262f2bdad7aa1176e2c1bbfedd..57158280b41c6552c82838e21384d925d5f7cde4 100644
--- a/boot/image-android.c
+++ b/boot/image-android.c
@@ -292,7 +292,7 @@ int android_image_get_kernel(const void *hdr,
 		len += strlen(img_data.kcmdline);
 	}
 
-	if (img_data.kcmdline_extra) {
+	if (*img_data.kcmdline_extra) {
 		printf("Kernel extra command line: %s\n", img_data.kcmdline_extra);
 		len += strlen(img_data.kcmdline_extra);
 	}
@@ -316,7 +316,7 @@ int android_image_get_kernel(const void *hdr,
 	if (*img_data.kcmdline)
 		strcat(newbootargs, img_data.kcmdline);
 
-	if (img_data.kcmdline_extra) {
+	if (*img_data.kcmdline_extra) {
 		strcat(newbootargs, " ");
 		strcat(newbootargs, img_data.kcmdline_extra);
 	}

-- 
2.34.1

[PATCH v2 2/3] boot: android: free newbootargs when done

[Nicolas Belin]

Free newbootargs when the concatenation is done and bootargs env
is set.

Fixes: 86f4695b ("image: Fix Android boot image support")
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Signed-off-by: Nicolas Belin <nbelin@baylibre.com>
---
 boot/image-android.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/boot/image-android.c b/boot/image-android.c
index 57158280b41c6552c82838e21384d925d5f7cde4..362a5c7435a3a8bcf7b674b96e31069a91a892b5 100644
--- a/boot/image-android.c
+++ b/boot/image-android.c
@@ -322,6 +322,7 @@ int android_image_get_kernel(const void *hdr,
 	}
 
 	env_set("bootargs", newbootargs);
+	free(newbootargs);
 
 	if (os_data) {
 		if (image_get_magic(ihdr) == IH_MAGIC) {

-- 
2.34.1

[PATCH v2 3/3] boot: android: rework bootargs concatenation

[Nicolas Belin]

Rework the bootargs concatenation allocating more accurately
the length that is needed.
Do not forget an extra byte for the null termination byte as,
in some cases, the allocation was 1 byte short.

Fixes: 86f4695b ("image: Fix Android boot image support")
Signed-off-by: Nicolas Belin <nbelin@baylibre.com>
---
 boot/image-android.c | 29 ++++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/boot/image-android.c b/boot/image-android.c
index 362a5c7435a3a8bcf7b674b96e31069a91a892b5..61ac312db7ad9ba6c55727469dd4ded61824c67c 100644
--- a/boot/image-android.c
+++ b/boot/image-android.c
@@ -287,37 +287,40 @@ int android_image_get_kernel(const void *hdr,
 	       kernel_addr, DIV_ROUND_UP(img_data.kernel_size, 1024));
 
 	int len = 0;
+	char *bootargs = env_get("bootargs");
+
+	if (bootargs)
+		len += strlen(bootargs);
+
 	if (*img_data.kcmdline) {
 		printf("Kernel command line: %s\n", img_data.kcmdline);
-		len += strlen(img_data.kcmdline);
+		len += strlen(img_data.kcmdline) + (len ? 1 : 0); /* +1 for extra space */
 	}
 
 	if (*img_data.kcmdline_extra) {
 		printf("Kernel extra command line: %s\n", img_data.kcmdline_extra);
-		len += strlen(img_data.kcmdline_extra);
+		len += strlen(img_data.kcmdline_extra) + (len ? 1 : 0); /* +1 for extra space */
 	}
 
-	char *bootargs = env_get("bootargs");
-	if (bootargs)
-		len += strlen(bootargs);
-
-	char *newbootargs = malloc(len + 2);
+	char *newbootargs = malloc(len + 1); /* +1 for the '\0' */
 	if (!newbootargs) {
 		puts("Error: malloc in android_image_get_kernel failed!\n");
 		return -ENOMEM;
 	}
-	*newbootargs = '\0';
+	*newbootargs = '\0'; /* set to Null in case no components below are present */
 
-	if (bootargs) {
+	if (bootargs)
 		strcpy(newbootargs, bootargs);
-		strcat(newbootargs, " ");
-	}
 
-	if (*img_data.kcmdline)
+	if (*img_data.kcmdline) {
+		if (*newbootargs) /* If there is something in newbootargs, a space is needed */
+			strcat(newbootargs, " ");
 		strcat(newbootargs, img_data.kcmdline);
+	}
 
 	if (*img_data.kcmdline_extra) {
-		strcat(newbootargs, " ");
+		if (*newbootargs) /* If there is something in newbootargs, a space is needed */
+			strcat(newbootargs, " ");
 		strcat(newbootargs, img_data.kcmdline_extra);
 	}
 

-- 
2.34.1

Re: [PATCH v2 3/3] boot: android: rework bootargs concatenation

[Mattijs Korpershoek]

Hi Nicolas,

Thank you for the patch.

On mar., déc. 17, 2024 at 14:29, Nicolas Belin <nbelin@baylibre.com> wrote:

> Rework the bootargs concatenation allocating more accurately
> the length that is needed.
> Do not forget an extra byte for the null termination byte as,
> in some cases, the allocation was 1 byte short.
>
> Fixes: 86f4695b ("image: Fix Android boot image support")
> Signed-off-by: Nicolas Belin <nbelin@baylibre.com>

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

> ---
>  boot/image-android.c | 29 ++++++++++++++++-------------
>  1 file changed, 16 insertions(+), 13 deletions(-)
>
> diff --git a/boot/image-android.c b/boot/image-android.c
> index 362a5c7435a3a8bcf7b674b96e31069a91a892b5..61ac312db7ad9ba6c55727469dd4ded61824c67c 100644
> --- a/boot/image-android.c
> +++ b/boot/image-android.c
> @@ -287,37 +287,40 @@ int android_image_get_kernel(const void *hdr,
>  	       kernel_addr, DIV_ROUND_UP(img_data.kernel_size, 1024));
>  
>  	int len = 0;
> +	char *bootargs = env_get("bootargs");
> +
> +	if (bootargs)
> +		len += strlen(bootargs);
> +
>  	if (*img_data.kcmdline) {
>  		printf("Kernel command line: %s\n", img_data.kcmdline);
> -		len += strlen(img_data.kcmdline);
> +		len += strlen(img_data.kcmdline) + (len ? 1 : 0); /* +1 for extra space */
>  	}
>  
>  	if (*img_data.kcmdline_extra) {
>  		printf("Kernel extra command line: %s\n", img_data.kcmdline_extra);
> -		len += strlen(img_data.kcmdline_extra);
> +		len += strlen(img_data.kcmdline_extra) + (len ? 1 : 0); /* +1 for extra space */
>  	}
>  
> -	char *bootargs = env_get("bootargs");
> -	if (bootargs)
> -		len += strlen(bootargs);
> -
> -	char *newbootargs = malloc(len + 2);
> +	char *newbootargs = malloc(len + 1); /* +1 for the '\0' */
>  	if (!newbootargs) {
>  		puts("Error: malloc in android_image_get_kernel failed!\n");
>  		return -ENOMEM;
>  	}
> -	*newbootargs = '\0';
> +	*newbootargs = '\0'; /* set to Null in case no components below are present */
>  
> -	if (bootargs) {
> +	if (bootargs)
>  		strcpy(newbootargs, bootargs);
> -		strcat(newbootargs, " ");
> -	}
>  
> -	if (*img_data.kcmdline)
> +	if (*img_data.kcmdline) {
> +		if (*newbootargs) /* If there is something in newbootargs, a space is needed */
> +			strcat(newbootargs, " ");
>  		strcat(newbootargs, img_data.kcmdline);
> +	}
>  
>  	if (*img_data.kcmdline_extra) {
> -		strcat(newbootargs, " ");
> +		if (*newbootargs) /* If there is something in newbootargs, a space is needed */
> +			strcat(newbootargs, " ");
>  		strcat(newbootargs, img_data.kcmdline_extra);
>  	}
>  
>
> -- 
> 2.34.1

Re: [PATCH v2 0/3] boot: android: rework the bootargs concatenation

[Mattijs Korpershoek]

Hi,

On Tue, 17 Dec 2024 14:29:07 +0100, Nicolas Belin wrote:
> Rework the bootargs concatenation logic to make the logic clearer
> and address several issues such as:
> - checking the value at the address kcmdline_extra instead of
> checking the address value itself
> - freeing the string that was malloced for the concatenation
> - making sure to malloc the right amount of bytes for the concatenated
> string, not forgetting the byte for the NULL termination
> 
> [...]

Thanks, Applied to https://source.denx.de/u-boot/custodians/u-boot-dfu (u-boot-dfu)

[1/3] boot: android: fix extra command line support
      https://source.denx.de/u-boot/custodians/u-boot-dfu/-/commit/53a0ddb6d3bed9f9607af79934a7625299c36793
[2/3] boot: android: free newbootargs when done
      https://source.denx.de/u-boot/custodians/u-boot-dfu/-/commit/fd8b44a81be55b33c7defbe96a1ddd79ed286eb4
[3/3] boot: android: rework bootargs concatenation
      https://source.denx.de/u-boot/custodians/u-boot-dfu/-/commit/9e5fad0f792539ae4258bc116bf408bb6faf7e82

--
Mattijs