From 8b14d7b22c61f17ccb869e0047d9df6dd9f50a9f Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> Date: Sun, 28 Nov 2010 19:46:50 -0200 Subject: [PATCH] wmi: use memcmp instead of strncmp to compare GUIDs While looking for the duplicates in /sys/class/wmi/, I couldn't find them. The code that looks for duplicates uses strncmp in a binary GUID, which may contain zero bytes. The right function is memcmp, which is also used in another section of wmi code. It was finding 49142400-C6A3-40FA-BADB-8A2652834100 as a duplicate of 39142400-C6A3-40FA-BADB-8A2652834100. Since the first byte is the fourth printed, they were found as equal by strncmp. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> Signed-off-by: Matthew Garrett <mjg@redhat.com> Cc: stable@kernel.org --- drivers/platform/x86/wmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index 104b77c87ef5a..aecd9a9b549f0 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -755,7 +755,7 @@ static bool guid_already_parsed(const char *guid_string) struct wmi_block *wblock; list_for_each_entry(wblock, &wmi_block_list, list) - if (strncmp(wblock->gblock.guid, guid_string, 16) == 0) + if (memcmp(wblock->gblock.guid, guid_string, 16) == 0) return true; return false; -- GitLab