[PATCH] x86_64: Disallow kprobes on NMI handlers
A kprobe executes IRET early and that could cause NMI recursion
and stack corruption.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index 8bb0aed..ee1b2da 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -372,7 +372,7 @@
static DEFINE_SPINLOCK(die_lock);
static int die_owner = -1;
-unsigned long oops_begin(void)
+unsigned __kprobes long oops_begin(void)
{
int cpu = safe_smp_processor_id();
unsigned long flags;
@@ -391,7 +391,7 @@
return flags;
}
-void oops_end(unsigned long flags)
+void __kprobes oops_end(unsigned long flags)
{
die_owner = -1;
bust_spinlocks(0);
@@ -400,7 +400,7 @@
panic("Oops");
}
-void __die(const char * str, struct pt_regs * regs, long err)
+void __kprobes __die(const char * str, struct pt_regs * regs, long err)
{
static int die_counter;
printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff,++die_counter);
@@ -432,7 +432,7 @@
do_exit(SIGSEGV);
}
-void die_nmi(char *str, struct pt_regs *regs)
+void __kprobes die_nmi(char *str, struct pt_regs *regs)
{
unsigned long flags = oops_begin();
@@ -575,7 +575,8 @@
}
}
-static void mem_parity_error(unsigned char reason, struct pt_regs * regs)
+static __kprobes void
+mem_parity_error(unsigned char reason, struct pt_regs * regs)
{
printk("Uhhuh. NMI received. Dazed and confused, but trying to continue\n");
printk("You probably have a hardware problem with your RAM chips\n");
@@ -585,7 +586,8 @@
outb(reason, 0x61);
}
-static void io_check_error(unsigned char reason, struct pt_regs * regs)
+static __kprobes void
+io_check_error(unsigned char reason, struct pt_regs * regs)
{
printk("NMI: IOCK error (debug interrupt?)\n");
show_registers(regs);
@@ -598,7 +600,8 @@
outb(reason, 0x61);
}
-static void unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
+static __kprobes void
+unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
{ printk("Uhhuh. NMI received for unknown reason %02x.\n", reason);
printk("Dazed and confused, but trying to continue\n");
printk("Do you have a strange power saving mode enabled?\n");
@@ -606,7 +609,7 @@
/* Runs on IST stack. This code must keep interrupts off all the time.
Nested NMIs are prevented by the CPU. */
-asmlinkage void default_do_nmi(struct pt_regs *regs)
+asmlinkage __kprobes void default_do_nmi(struct pt_regs *regs)
{
unsigned char reason = 0;
int cpu;
@@ -658,7 +661,7 @@
/* Help handler running on IST stack to switch back to user stack
for scheduling or signal handling. The actual stack switch is done in
entry.S */
-asmlinkage struct pt_regs *sync_regs(struct pt_regs *eregs)
+asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
{
struct pt_regs *regs = eregs;
/* Did already sync */