[PATCH 5.4 291/340] arm64: kexec_file: fix memory leakage in create_dtb() when fdt_open_into() fails

[Greg Kroah-Hartman]

From: qiuguorui1 <qiuguorui1@xxxxxxxxxx>

commit 656d1d58d8e0958d372db86c24f0b2ea36f50888 upstream.

in function create_dtb(), if fdt_open_into() fails, we need to vfree
buf before return.

Fixes: 52b2a8af7436 ("arm64: kexec_file: load initrd and device-tree")
Cc: stable@xxxxxxxxxxxxxxx # v5.0
Signed-off-by: qiuguorui1 <qiuguorui1@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210218125900.6810-1-qiuguorui1@xxxxxxxxxx
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/arm64/kernel/machine_kexec_file.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -150,8 +150,10 @@ static int create_dtb(struct kimage *ima
 
 		/* duplicate a device tree blob */
 		ret = fdt_open_into(initial_boot_params, buf, buf_size);
-		if (ret)
+		if (ret) {
+			vfree(buf);
 			return -EINVAL;
+		}
 
 		ret = setup_dtb(image, initrd_load_addr, initrd_len,
 				cmdline, buf);