KEYS: encrypted: Return early on allocation failure and drop goto

[PATCH] KEYS: encrypted: Return early on allocation failure and drop goto

Posted by Thorsten Blum 3 months, 1 week ago

Return ERR_PTR(-ENOMEM) immediately if memory allocation fails, instead
of using goto and returning a NULL pointer, and remove the now-unused
'out' label.

At the call site, check 'ascii_buf' with IS_ERR() and propagate the
error code returned by datablob_format().

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 security/keys/encrypted-keys/encrypted.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index be1f2118447c..25df00b7dbe9 100644
--- a/security/keys/encrypted-keys/encrypted.c
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -276,7 +276,7 @@ static char *datablob_format(struct encrypted_key_payload *epayload,
 
 	ascii_buf = kmalloc(asciiblob_len + 1, GFP_KERNEL);
 	if (!ascii_buf)
-		goto out;
+		return ERR_PTR(-ENOMEM);
 
 	ascii_buf[asciiblob_len] = '\0';
 
@@ -288,7 +288,6 @@ static char *datablob_format(struct encrypted_key_payload *epayload,
 	bufp = &ascii_buf[len];
 	for (i = 0; i < (asciiblob_len - len) / 2; i++)
 		bufp = hex_byte_pack(bufp, iv[i]);
-out:
 	return ascii_buf;
 }
 
@@ -932,8 +931,8 @@ static long encrypted_read(const struct key *key, char *buffer,
 		goto out;
 
 	ascii_buf = datablob_format(epayload, asciiblob_len);
-	if (!ascii_buf) {
-		ret = -ENOMEM;
+	if (IS_ERR(ascii_buf)) {
+		ret = PTR_ERR(ascii_buf);
 		goto out;
 	}
 
-- 
2.51.0

Re: [PATCH] KEYS: encrypted: Return early on allocation failure and drop goto

Posted by Jarkko Sakkinen 3 months ago

On Wed, Oct 29, 2025 at 05:31:56PM +0100, Thorsten Blum wrote:
> Return ERR_PTR(-ENOMEM) immediately if memory allocation fails, instead
> of using goto and returning a NULL pointer, and remove the now-unused
> 'out' label.
> 
> At the call site, check 'ascii_buf' with IS_ERR() and propagate the
> error code returned by datablob_format().
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
> ---
>  security/keys/encrypted-keys/encrypted.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
> index be1f2118447c..25df00b7dbe9 100644
> --- a/security/keys/encrypted-keys/encrypted.c
> +++ b/security/keys/encrypted-keys/encrypted.c
> @@ -276,7 +276,7 @@ static char *datablob_format(struct encrypted_key_payload *epayload,
>  
>  	ascii_buf = kmalloc(asciiblob_len + 1, GFP_KERNEL);
>  	if (!ascii_buf)
> -		goto out;
> +		return ERR_PTR(-ENOMEM);
>  
>  	ascii_buf[asciiblob_len] = '\0';
>  
> @@ -288,7 +288,6 @@ static char *datablob_format(struct encrypted_key_payload *epayload,
>  	bufp = &ascii_buf[len];
>  	for (i = 0; i < (asciiblob_len - len) / 2; i++)
>  		bufp = hex_byte_pack(bufp, iv[i]);
> -out:
>  	return ascii_buf;
>  }
>  
> @@ -932,8 +931,8 @@ static long encrypted_read(const struct key *key, char *buffer,
>  		goto out;
>  
>  	ascii_buf = datablob_format(epayload, asciiblob_len);
> -	if (!ascii_buf) {
> -		ret = -ENOMEM;
> +	if (IS_ERR(ascii_buf)) {
> +		ret = PTR_ERR(ascii_buf);
>  		goto out;
>  	}
>  
> -- 
> 2.51.0
> 

No thank you as this does not really fix anything.

BR, Jarkko

Re: [PATCH] KEYS: encrypted: Return early on allocation failure and drop goto

Posted by Serge E. Hallyn 3 months, 1 week ago

On Wed, Oct 29, 2025 at 05:31:56PM +0100, Thorsten Blum wrote:
> Return ERR_PTR(-ENOMEM) immediately if memory allocation fails, instead
> of using goto and returning a NULL pointer, and remove the now-unused
> 'out' label.
> 
> At the call site, check 'ascii_buf' with IS_ERR() and propagate the
> error code returned by datablob_format().
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>

It seems like purely personal preference, but I don't see any
error in it, so in that sense

Reviewed-by: Serge Hallyn <serge@hallyn.com>


> ---
>  security/keys/encrypted-keys/encrypted.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
> index be1f2118447c..25df00b7dbe9 100644
> --- a/security/keys/encrypted-keys/encrypted.c
> +++ b/security/keys/encrypted-keys/encrypted.c
> @@ -276,7 +276,7 @@ static char *datablob_format(struct encrypted_key_payload *epayload,
>  
>  	ascii_buf = kmalloc(asciiblob_len + 1, GFP_KERNEL);
>  	if (!ascii_buf)
> -		goto out;
> +		return ERR_PTR(-ENOMEM);
>  
>  	ascii_buf[asciiblob_len] = '\0';
>  
> @@ -288,7 +288,6 @@ static char *datablob_format(struct encrypted_key_payload *epayload,
>  	bufp = &ascii_buf[len];
>  	for (i = 0; i < (asciiblob_len - len) / 2; i++)
>  		bufp = hex_byte_pack(bufp, iv[i]);
> -out:
>  	return ascii_buf;
>  }
>  
> @@ -932,8 +931,8 @@ static long encrypted_read(const struct key *key, char *buffer,
>  		goto out;
>  
>  	ascii_buf = datablob_format(epayload, asciiblob_len);
> -	if (!ascii_buf) {
> -		ret = -ENOMEM;
> +	if (IS_ERR(ascii_buf)) {
> +		ret = PTR_ERR(ascii_buf);
>  		goto out;
>  	}
>  
> -- 
> 2.51.0