From: Arvind Sankar <nivedita@alum.mit.edu>
Date: Mon, 18 May 2020 15:07:05 -0400
Subject: efi/printf: Handle null string input
Patch-mainline: v5.8-rc1
Git-commit: fb031937a86874e6d663542bdbd83e310c13610e
References: jsc#SLE-16407
Print "(null)" for 's' if the input is a NULL pointer.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-14-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
drivers/firmware/efi/libstub/vsprintf.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/drivers/firmware/efi/libstub/vsprintf.c
+++ b/drivers/firmware/efi/libstub/vsprintf.c
@@ -14,6 +14,7 @@
#include <linux/compiler.h>
#include <linux/ctype.h>
+#include <linux/limits.h>
#include <linux/string.h>
static int skip_atoi(const char **s)
@@ -356,7 +357,11 @@ int vsprintf(char *buf, const char *fmt,
continue;
case 's':
+ if (precision < 0)
+ precision = INT_MAX;
s = va_arg(args, char *);
+ if (!s)
+ s = precision < 6 ? "" : "(null)";
len = strnlen(s, precision);
if (!(flags & LEFT))