Protect dtrace_getpcstack() from a NULL stack pointer in a trap frame
Found when trying to use lockstat on a POWER9, the stack pointer (r1) could be NULL, and result in a NULL pointer dereference, crashing the kernel.
This commit is contained in:
parent
8b20f97570
commit
5e91185bb1
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=334370
@ -98,6 +98,7 @@ static __inline uintptr_t
|
||||
dtrace_next_sp(uintptr_t sp)
|
||||
{
|
||||
vm_offset_t callpc;
|
||||
uintptr_t *r1;
|
||||
struct trapframe *frame;
|
||||
|
||||
#ifdef __powerpc64__
|
||||
@ -114,7 +115,10 @@ dtrace_next_sp(uintptr_t sp)
|
||||
callpc + OFFSET == (vm_offset_t) &asttrapexit)) {
|
||||
/* Access the trap frame */
|
||||
frame = (struct trapframe *)(sp + FRAME_OFFSET);
|
||||
return (*(uintptr_t *)(frame->fixreg[1]));
|
||||
r1 = (uintptr_t *)frame->fixreg[1];
|
||||
if (r1 == NULL)
|
||||
return (0);
|
||||
return (*r1);
|
||||
}
|
||||
|
||||
return (*(uintptr_t*)sp);
|
||||
|
Loading…
Reference in New Issue
Block a user