4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
[ Upstream commit 0dad3a3014a0b9e72521ff44f17e0054f43dcdea ]
If mce_device_init() fails then the mce device pointer is NULL and the
AMD mce code happily dereferences it.
Add a sanity check.
Reported-by: Markus Trippelsdorf <markus@xxxxxxxxxxxxxxx>
Reported-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/mcheck/mce_amd.c | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -955,6 +955,9 @@ static int threshold_create_bank(unsigne
const char *name = get_name(bank, NULL);
int err = 0;
+ if (!dev)
+ return -ENODEV;
+
if (is_shared_bank(bank)) {
nb = node_to_amd_nb(amd_get_nb_id(cpu));