[PATCH v3 1/2] Fix the error reporting of get_bct_size_from_image() and read_bct_file()

[PATCH v3 1/2] Fix the error reporting of get_bct_size_from_image() and read_bct_file()

[Alban Bedel]

get_bct_size_from_image() and read_bct_file() should return negative
error codes, so add the missing minus signs. Also fix the return value
check on get_bct_size_from_image(), a negative value indicate an error
not zero.

Signed-off-by: Alban Bedel <alban.bedel-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org>
---
Changelog:
v2: * Fixed the same bug in read_bct_file()
---
 src/cbootimage.c  | 2 +-
 src/data_layout.c | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/cbootimage.c b/src/cbootimage.c
index da1d1a5..fc99af2 100644
--- a/src/cbootimage.c
+++ b/src/cbootimage.c
@@ -239,7 +239,7 @@ main(int argc, char *argv[])
 
 		/* Get BCT_SIZE from input image file  */
 		bct_size = get_bct_size_from_image(&context);
-		if (!bct_size) {
+		if (bct_size < 0) {
 			printf("Error: Invalid input image file %s\n",
 			context.input_image_filename);
 			goto fail;
diff --git a/src/data_layout.c b/src/data_layout.c
index 5d3fe10..460310d 100644
--- a/src/data_layout.c
+++ b/src/data_layout.c
@@ -792,7 +792,7 @@ read_bct_file(struct build_image_context_rec *context)
 	free(bct_storage);
 
 	if (!data_is_valid_bct(context))
-		return ENODATA;
+		return -ENODATA;
 
 	return err;
 }
@@ -1050,11 +1050,11 @@ int get_bct_size_from_image(build_image_context *context)
 
 	fp = fopen(context->input_image_filename, "r");
 	if (!fp)
-		return ENODATA;
+		return -ENODATA;
 
 	if (fread(buffer, 1, NVBOOT_CONFIG_TABLE_SIZE_MAX, fp) != NVBOOT_CONFIG_TABLE_SIZE_MAX) {
 		fclose(fp);
-		return ENODATA;
+		return -ENODATA;
 	}
 
 	context->bct = buffer;
-- 
2.6.3

[PATCH v3 2/2] Fix image update with image smaller than 10KiB

[Alban Bedel]

The BCT size check assume a quiet large image, however if the image
doesn't contains a bootloader it won't be that large. Change the size
check to only read the minimum data needed to verify the BCT version
and get the size.

Signed-off-by: Alban Bedel <alban.bedel-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org>
--
Changelog:
v2: * Add a comment to explain the value of NVBOOT_CONFIG_TABLE_SIZE_MIN
v3: * Only read the minimum data needed
---
 src/cbootimage.h  | 14 ++++++++++++++
 src/data_layout.c |  4 ++--
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/cbootimage.h b/src/cbootimage.h
index 63f0ee9..ba2d997 100644
--- a/src/cbootimage.h
+++ b/src/cbootimage.h
@@ -49,6 +49,20 @@
 
 #define MAX_MTS_SIZE (4 * 1024 * 1024)
 
+/* Minimum size to read to at least be able to validate a BCT, it must
+ * include the boot_data_version field with any BCT version while not
+ * beeing larger than the smallest possible BCT. The currently supported
+ * BCT are as follow:
+ *
+ * Chip		Version offset	Total size
+ * T20		32		4080
+ * T30		32		6128
+ * T114		1792		8192
+ * T124		1744		8192
+ * T132		1744		8704
+ * T210		1328		10240
+ */
+#define NVBOOT_CONFIG_TABLE_SIZE_MIN 4080
 #define NVBOOT_CONFIG_TABLE_SIZE_MAX (10 * 1024)
 
 /*
diff --git a/src/data_layout.c b/src/data_layout.c
index 460310d..0eace5f 100644
--- a/src/data_layout.c
+++ b/src/data_layout.c
@@ -1044,7 +1044,7 @@ int data_is_valid_bct(build_image_context *context)
 
 int get_bct_size_from_image(build_image_context *context)
 {
-	u_int8_t buffer[NVBOOT_CONFIG_TABLE_SIZE_MAX];
+	u_int8_t buffer[NVBOOT_CONFIG_TABLE_SIZE_MIN];
 	u_int32_t bct_size = 0;
 	FILE *fp;
 
@@ -1052,7 +1052,7 @@ int get_bct_size_from_image(build_image_context *context)
 	if (!fp)
 		return -ENODATA;
 
-	if (fread(buffer, 1, NVBOOT_CONFIG_TABLE_SIZE_MAX, fp) != NVBOOT_CONFIG_TABLE_SIZE_MAX) {
+	if (fread(buffer, 1, NVBOOT_CONFIG_TABLE_SIZE_MIN, fp) != NVBOOT_CONFIG_TABLE_SIZE_MIN) {
 		fclose(fp);
 		return -ENODATA;
 	}
-- 
2.6.3

Re: [PATCH v3 1/2] Fix the error reporting of get_bct_size_from_image() and read_bct_file()

[Stephen Warren]

On 12/08/2015 07:32 AM, Alban Bedel wrote:
> get_bct_size_from_image() and read_bct_file() should return negative
> error codes, so add the missing minus signs. Also fix the return value
> check on get_bct_size_from_image(), a negative value indicate an error
> not zero.

I've applied the series.