[PATCH 6.9 367/374] efi: libstub: only free priv.runtime_map when allocated

Greg Kroah-Hartman
2024-06-06T14:11:34Z

From: Hagar Hemdan <hagarhem@amazon.com>

commit 4b2543f7e1e6b91cfc8dd1696e3cdf01c3ac8974 upstream.

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")
Cc: <stable@vger.kernel.org>
Signed-off-by: Hagar Hemdan <hagarhem@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/firmware/efi/libstub/fdt.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -335,8 +335,8 @@ fail_free_new_fdt:

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;
}