[PATCH] KDB: Fix incorrect treatment of numbers in the CLI

[Nir Lichtman]

Problem: In many cases, KDB treats invalid commands as numbers and
instead of printing a usage error, goes ahead and just prints the number
in hex

Example: This can be demonstrated when typing for example "aaazzz", this
confuses KDB into thinking this is the hexadecimal 0xAAA

Solution: Before assuming that the input from the user is a number,
check that it contains only characters that represent numbers.
Also, along the way, transition to using kstrtoul instead of
simple_strtoul (better practice as stated in the definition of the
function)

Signed-off-by: Nir Lichtman <nir@xxxxxxxxxxxx>
---
 kernel/debug/kdb/kdb_main.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index f5f7d7fb5936..4efdc4d25a59 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -402,18 +402,18 @@ static void kdb_printenv(void)
  */
 int kdbgetularg(const char *arg, unsigned long *value)
 {
-	char *endp;
 	unsigned long val;
 
-	val = simple_strtoul(arg, &endp, 0);
+	if ((strpbrk(arg, hex_asc) == NULL)
+	 && (strpbrk(arg, hex_asc_upper) == NULL))
+		return KDB_BADINT;
 
-	if (endp == arg) {
+	if (kstrtoul(arg, 0, &val) != 0) {
 		/*
 		 * Also try base 16, for us folks too lazy to type the
 		 * leading 0x...
 		 */
-		val = simple_strtoul(arg, &endp, 16);
-		if (endp == arg)
+		if (kstrtoul(arg, 16, &val) != 0)
 			return KDB_BADINT;
 	}
 
-- 
2.39.2