From d438fabce7860df3cb9337776be6f90b59ced8ed Mon Sep 17 00:00:00 2001 From: Marco Elver Date: Thu, 25 Feb 2021 17:19:08 -0800 Subject: kfence: use pt_regs to generate stack trace on faults Instead of removing the fault handling portion of the stack trace based on the fault handler's name, just use struct pt_regs directly. Change kfence_handle_page_fault() to take a struct pt_regs, and plumb it through to kfence_report_error() for out-of-bounds, use-after-free, or invalid access errors, where pt_regs is used to generate the stack trace. If the kernel is a DEBUG_KERNEL, also show registers for more information. Link: https://lkml.kernel.org/r/20201105092133.2075331-1-elver@google.com Signed-off-by: Marco Elver Suggested-by: Mark Rutland Acked-by: Mark Rutland Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Jann Horn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/include/asm/kfence.h | 6 ------ arch/x86/mm/fault.c | 2 +- 2 files changed, 1 insertion(+), 7 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/kfence.h b/arch/x86/include/asm/kfence.h index a0659dbd93ea..97bbb4a9083a 100644 --- a/arch/x86/include/asm/kfence.h +++ b/arch/x86/include/asm/kfence.h @@ -16,12 +16,6 @@ #include #include -/* - * The page fault handler entry function, up to which the stack trace is - * truncated in reports. - */ -#define KFENCE_SKIP_ARCH_FAULT_HANDLER "asm_exc_page_fault" - /* Force 4K pages for __kfence_pool. */ static inline bool arch_kfence_init_pool(void) { diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 99fe6d3e690d..38868b4ce8b0 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -682,7 +682,7 @@ page_fault_oops(struct pt_regs *regs, unsigned long error_code, efi_crash_gracefully_on_page_fault(address); /* Only not-present faults should be handled by KFENCE. */ - if (!(error_code & X86_PF_PROT) && kfence_handle_page_fault(address)) + if (!(error_code & X86_PF_PROT) && kfence_handle_page_fault(address, regs)) return; oops: -- cgit v1.2.3