[PATCH] efi: fix memory leak in krealloc failure handling

From: Kuan-Wei Chiu
Date: Sun Sep 24 2023 - 10:26:48 EST


In the previous code, there was a memory leak issue where the
previously allocated memory was not freed upon a failed krealloc
operation. This patch addresses the problem by releasing the old memory
before setting the pointer to NULL in case of a krealloc failure. This
ensures that memory is properly managed and avoids potential memory
leaks.

Signed-off-by: Kuan-Wei Chiu <visitorckw@xxxxxxxxx>
---
drivers/firmware/efi/efi.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index ce20a60676f0..1974f0ad32ba 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -273,9 +273,13 @@ static __init int efivar_ssdt_load(void)
if (status == EFI_NOT_FOUND) {
break;
} else if (status == EFI_BUFFER_TOO_SMALL) {
- name = krealloc(name, name_size, GFP_KERNEL);
- if (!name)
+ efi_char16_t *name_tmp =
+ krealloc(name, name_size, GFP_KERNEL);
+ if (!name_tmp) {
+ kfree(name);
return -ENOMEM;
+ }
+ name = name_tmp;
continue;
}

--
2.25.1