[PATCH] hab: writing the same srk hash is not an error

[PATCH] hab: writing the same srk hash is not an error

[Stefan Kerkmann]

Before this commit writing the same srk hash twice failed with an error.
This is inconsistent with other invocations of the hab tool e.g.: `hab
-l -p` doesn't fail if the lockdown bit is already set.

So let's align the behavior by only throwing an error if we attempt to
write a srk hash that is different from the one that is already burned.

Signed-off-by: Stefan Kerkmann <s.kerkmann@pengutronix.de>
---
 drivers/hab/hab.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/hab/hab.c b/drivers/hab/hab.c
index 4e9f96c98b619d12d069986aa688b92d48f3442c..1c747e8a3e52fdfc0240b5794fbffe9a2a562bb2 100644
--- a/drivers/hab/hab.c
+++ b/drivers/hab/hab.c
@@ -470,12 +470,13 @@ int imx_hab_write_srk_hash(const void *buf, unsigned flags)
 	}
 
 	if (imx_hab_srk_hash_valid(cursrk)) {
-		char *str = "Current SRK hash is valid";
-
 		if (flags & IMX_SRK_HASH_FORCE) {
-			pr_warn("%s, ignoring\n", str);
+			pr_warn("Current SRK hash is valid, ignoring\n");
+		} else if (memcmp(cursrk, buf, SRK_HASH_SIZE) == 0) {
+			pr_info("Current SRK hash is equal, nothing to do\n");
+			return 0;
 		} else {
-			pr_err("%s, refusing to burn again\n", str);
+			pr_err("Current SRK hash is different, refusing to burn again\n");
 			return -EEXIST;
 		}
 	}

---
base-commit: f49c873d7ec78a2df7bd3c7a86f5372fb1666517
change-id: 20250709-fix-hab-equal-hash-writes-87c28792acf4

Best regards,
-- 
Stefan Kerkmann <s.kerkmann@pengutronix.de>

Re: [PATCH] hab: writing the same srk hash is not an error

[Ahmad Fatoum]

On 09.07.25 09:42, Stefan Kerkmann wrote:
> Before this commit writing the same srk hash twice failed with an error.
> This is inconsistent with other invocations of the hab tool e.g.: `hab
> -l -p` doesn't fail if the lockdown bit is already set.
> 
> So let's align the behavior by only throwing an error if we attempt to
> write a srk hash that is different from the one that is already burned.
> 
> Signed-off-by: Stefan Kerkmann <s.kerkmann@pengutronix.de>

Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>

> ---
>  drivers/hab/hab.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/hab/hab.c b/drivers/hab/hab.c
> index 4e9f96c98b619d12d069986aa688b92d48f3442c..1c747e8a3e52fdfc0240b5794fbffe9a2a562bb2 100644
> --- a/drivers/hab/hab.c
> +++ b/drivers/hab/hab.c
> @@ -470,12 +470,13 @@ int imx_hab_write_srk_hash(const void *buf, unsigned flags)
>  	}
>  
>  	if (imx_hab_srk_hash_valid(cursrk)) {
> -		char *str = "Current SRK hash is valid";
> -
>  		if (flags & IMX_SRK_HASH_FORCE) {
> -			pr_warn("%s, ignoring\n", str);
> +			pr_warn("Current SRK hash is valid, ignoring\n");
> +		} else if (memcmp(cursrk, buf, SRK_HASH_SIZE) == 0) {
> +			pr_info("Current SRK hash is equal, nothing to do\n");
> +			return 0;
>  		} else {
> -			pr_err("%s, refusing to burn again\n", str);
> +			pr_err("Current SRK hash is different, refusing to burn again\n");
>  			return -EEXIST;
>  		}
>  	}
> 
> ---
> base-commit: f49c873d7ec78a2df7bd3c7a86f5372fb1666517
> change-id: 20250709-fix-hab-equal-hash-writes-87c28792acf4
> 
> Best regards,


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