From a769b05eeed7accc4019a1ed9799dd72067f1ce8 Mon Sep 17 00:00:00 2001
From: Khazhismel Kumykov <khazhy@chromium.org>
Date: Tue, 17 Jan 2023 17:02:12 -0800
Subject: [PATCH] gsmi: fix null-deref in gsmi_get_variable
Git-commit: a769b05eeed7accc4019a1ed9799dd72067f1ce8
Patch-mainline: v6.2-rc5
References: git-fixes
We can get EFI variables without fetching the attribute, so we must
allow for that in gsmi.
commit 859748255b43 ("efi: pstore: Omit efivars caching EFI varstore
access layer") added a new get_variable call with attr=NULL, which
triggers panic in gsmi.
Fixes: 74c5b31c6618 ("driver: Google EFI SMI")
Cc: stable <stable@kernel.org>
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Link: https://lore.kernel.org/r/20230118010212.1268474-1-khazhy@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/firmware/google/gsmi.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/google/gsmi.c
index 4e2575dfeb90..871bedf533a8 100644
--- a/drivers/firmware/google/gsmi.c
+++ b/drivers/firmware/google/gsmi.c
@@ -361,9 +361,10 @@ static efi_status_t gsmi_get_variable(efi_char16_t *name,
memcpy(data, gsmi_dev.data_buf->start, *data_size);
/* All variables are have the following attributes */
- *attr = EFI_VARIABLE_NON_VOLATILE |
- EFI_VARIABLE_BOOTSERVICE_ACCESS |
- EFI_VARIABLE_RUNTIME_ACCESS;
+ if (attr)
+ *attr = EFI_VARIABLE_NON_VOLATILE |
+ EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_RUNTIME_ACCESS;
}
spin_unlock_irqrestore(&gsmi_dev.lock, flags);
--
2.35.3