From db65dd60fb11e3d38dbdd9a2e2f64d6ea7ef7576 Mon Sep 17 00:00:00 2001 From: Arthur Heymans Date: Fri, 25 Nov 2022 13:36:26 +0100 Subject: [PATCH] cpu/x86/mp_init.c: Improve AP entry point Make sure that a pointer exists before dereferencing it. Change-Id: I1a9833bb9686451224249efe599346f64dc37874 Signed-off-by: Arthur Heymans Reviewed-on: https://review.coreboot.org/c/coreboot/+/70011 Tested-by: build bot (Jenkins) Reviewed-by: Elyes Haouas --- src/cpu/x86/mp_init.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/src/cpu/x86/mp_init.c b/src/cpu/x86/mp_init.c index acc1323967..f00418547e 100644 --- a/src/cpu/x86/mp_init.c +++ b/src/cpu/x86/mp_init.c @@ -182,9 +182,16 @@ static asmlinkage void ap_init(unsigned int index) enable_lapic(); setup_lapic_interrupts(); - struct device *dev = g_cpu_bus->children; - for (unsigned int i = index; i > 0; i--) - dev = dev->sibling; + struct device *dev; + int i = 0; + for (dev = g_cpu_bus->children; dev; dev = dev->sibling) + if (i++ == index) + break; + + if (!dev) { + printk(BIOS_ERR, "Could not find allocated device for index %u\n", index); + return; + } set_cpu_info(index, dev);