[PATCH 4.19 041/113] ipmi: ipmi_si_hardcode.c: init si_type array to fix a crash

[Greg Kroah-Hartman]

[ Upstream commit a885bcfd152f97b25005298ab2d6b741aed9b49c ]

The intended behavior of function ipmi_hardcode_init_one() is to default
to kcs interface when no type argument is presented when initializing
ipmi with hard coded addresses.

However, the array of char pointers allocated on the stack by function
ipmi_hardcode_init() was not inited to zeroes, so it contained stack
debris.

Consequently, passing the cruft stored in this array to function
ipmi_hardcode_init_one() caused a crash when it was unable to detect
that the char * being passed was nonsense and tried to access the
address specified by the bogus pointer.

The fix is simply to initialize the si_type array to zeroes, so if
there were no type argument given to at the command line, function
ipmi_hardcode_init_one() could properly default to the kcs interface.

Signed-off-by: Tony Camuso <tcamuso@xxxxxxxxxx>
Message-Id: <1554837603-40299-1-git-send-email-tcamuso@xxxxxxxxxx>
Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/char/ipmi/ipmi_si_hardcode.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/char/ipmi/ipmi_si_hardcode.c b/drivers/char/ipmi/ipmi_si_hardcode.c
index 9ae2405c28bbd..0c28e872ad3ae 100644
--- a/drivers/char/ipmi/ipmi_si_hardcode.c
+++ b/drivers/char/ipmi/ipmi_si_hardcode.c
@@ -200,6 +200,8 @@ void __init ipmi_hardcode_init(void)
 	char *str;
 	char *si_type[SI_MAX_PARMS];
 
+	memset(si_type, 0, sizeof(si_type));
+
 	/* Parse out the si_type string into its components. */
 	str = si_type_str;
 	if (*str != '\0') {
-- 
2.20.1