efi: pstore: Drop efivar lock when efi_pstore_open() returns with an error

[PATCH] efi: pstore: Drop efivar lock when efi_pstore_open() returns with an error

Posted by Thomas Huth 1 month, 2 weeks ago

From: Thomas Huth <thuth@redhat.com>

If kzalloc fails, the function returns -ENOMEM without calling
efivar_unlock(). Since open() returned  an error, the calling site
in pstore_get_backend_records() won't call the close() function, so
the lock is never released. Thus drop the lock in case of errors here.

Fixes: 859748255b434 ("efi: pstore: Omit efivars caching EFI varstore access layer")
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 drivers/firmware/efi/efi-pstore.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c
index a253b61449459..a5db3534f0a63 100644
--- a/drivers/firmware/efi/efi-pstore.c
+++ b/drivers/firmware/efi/efi-pstore.c
@@ -60,8 +60,10 @@ static int efi_pstore_open(struct pstore_info *psi)
 		return err;
 
 	psi->data = kzalloc(record_size, GFP_KERNEL);
-	if (!psi->data)
+	if (!psi->data) {
+		efivar_unlock();
 		return -ENOMEM;
+	}
 
 	return 0;
 }
-- 
2.53.0

Re: [PATCH] efi: pstore: Drop efivar lock when efi_pstore_open() returns with an error

Posted by Ard Biesheuvel 1 month, 2 weeks ago

Hi Thomas,

On Mon, 27 Apr 2026, at 17:56, Thomas Huth wrote:
> From: Thomas Huth <thuth@redhat.com>
>
> If kzalloc fails, the function returns -ENOMEM without calling
> efivar_unlock(). Since open() returned  an error, the calling site
> in pstore_get_backend_records() won't call the close() function, so
> the lock is never released. Thus drop the lock in case of errors here.
>
> Fixes: 859748255b434 ("efi: pstore: Omit efivars caching EFI varstore 
> access layer")
> Assisted-by: Claude:claude-opus-4-6
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>  drivers/firmware/efi/efi-pstore.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>

Queued in efi/urgent - thanks.

> diff --git a/drivers/firmware/efi/efi-pstore.c 
> b/drivers/firmware/efi/efi-pstore.c
> index a253b61449459..a5db3534f0a63 100644
> --- a/drivers/firmware/efi/efi-pstore.c
> +++ b/drivers/firmware/efi/efi-pstore.c
> @@ -60,8 +60,10 @@ static int efi_pstore_open(struct pstore_info *psi)
>  		return err;
> 
>  	psi->data = kzalloc(record_size, GFP_KERNEL);
> -	if (!psi->data)
> +	if (!psi->data) {
> +		efivar_unlock();
>  		return -ENOMEM;
> +	}
> 
>  	return 0;
>  }
> -- 
> 2.53.0