[tip: x86/misc] tools/x86/kcpuid: Check last token too

[tip-bot2 for Borislav Petkov]

The following commit has been merged into the x86/misc branch of tip:

Commit-ID:     e20f67026b5ead2afc5627e98b45e6b65e7fb38c
Gitweb:        https://git.kernel.org/tip/e20f67026b5ead2afc5627e98b45e6b65e7fb38c
Author:        Borislav Petkov <bp@xxxxxxx>
AuthorDate:    Mon, 15 Mar 2021 13:08:35 +01:00
Committer:     Borislav Petkov <bp@xxxxxxx>
CommitterDate: Thu, 18 Mar 2021 11:36:01 +01:00

tools/x86/kcpuid: Check last token too

Input lines like

  0x8000001E,     0, EAX,   31:0, Extended APIC ID

where the short name is missing lead to a segfault because the loop
takes the long name for the short name and tokens[5] becomes NULL which
explodes later in strcpy().

Check its value too before further processing.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Acked-by: Feng Tang <feng.tang@xxxxxxxxx>
Link: https://lkml.kernel.org/r/20210315125901.30315-1-bp@xxxxxxxxx
---
 tools/arch/x86/kcpuid/kcpuid.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/arch/x86/kcpuid/kcpuid.c b/tools/arch/x86/kcpuid/kcpuid.c
index 6048da3..dae7551 100644
--- a/tools/arch/x86/kcpuid/kcpuid.c
+++ b/tools/arch/x86/kcpuid/kcpuid.c
@@ -324,6 +324,8 @@ static int parse_line(char *line)
 		str = NULL;
 	}
 	tokens[5] = strtok(str, "\n");
+	if (!tokens[5])
+		goto err_exit;
 
 	/* index/main-leaf */
 	index = strtoull(tokens[0], NULL, 0);