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From: Hagar Hemdan <hagarhem@amazon.com>
To:
CC: Maximilian Heyne <mheyne@amazon.de>, Pratyush Yadav <ptyadav@amazon.de>,
	Norbert Manthey <nmanthey@amazon.de>, <stable@vger.kernel.org>, Hagar Hemdan
	<hagarhem@amazon.com>, Ard Biesheuvel <ardb@kernel.org>,
	<linux-efi@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH] efi: libstub: only free priv.runtime_map when allocated
Date: Tue, 23 Apr 2024 13:36:33 +0000
Message-ID: <20240423133635.19679-1-hagarhem@amazon.com>
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priv.runtime_map is only allocated when efi_novamap is not set.
Otherwise, it is an uninitialized value.
In the error path, it is freed unconditionally.
Avoid passing an uninitialized value to free_pool.
Free priv.runtime_map only when it was allocated.

This bug was discovered and resolved using Coverity Static Analysis
Security Testing (SAST) by Synopsys, Inc.

Fixes: f80d26043af9 ("efi: libstub: avoid efi_get_memory_map() for allocating the virt map")
Signed-off-by: Hagar Hemdan <hagarhem@amazon.com>
---
 drivers/firmware/efi/libstub/fdt.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index 70e9789ff9de..6a337f1f8787 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -335,8 +335,8 @@ efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
 
 fail:
 	efi_free(fdt_size, fdt_addr);
-
-	efi_bs_call(free_pool, priv.runtime_map);
+	if (!efi_novamap)
+		efi_bs_call(free_pool, priv.runtime_map);
 
 	return EFI_LOAD_ERROR;
 }
-- 
2.40.1