diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/kernel/stacktrace.c | 40 | ||||
| -rw-r--r-- | arch/arm/lib/call_with_stack.S | 2 |
2 files changed, 35 insertions, 7 deletions
diff --git a/arch/arm/kernel/stacktrace.c b/arch/arm/kernel/stacktrace.c index d0fa2037460a..af87040b0353 100644 --- a/arch/arm/kernel/stacktrace.c +++ b/arch/arm/kernel/stacktrace.c @@ -9,6 +9,8 @@ #include <asm/stacktrace.h> #include <asm/traps.h> +#include "reboot.h" + #if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) /* * Unwind the current stack frame and store the new register values in the @@ -39,29 +41,53 @@ * Note that with framepointer enabled, even the leaf functions have the same * prologue and epilogue, therefore we can ignore the LR value in this case. */ -int notrace unwind_frame(struct stackframe *frame) + +extern unsigned long call_with_stack_end; + +static int frame_pointer_check(struct stackframe *frame) { unsigned long high, low; unsigned long fp = frame->fp; + unsigned long pc = frame->pc; + + /* + * call_with_stack() is the only place we allow SP to jump from one + * stack to another, with FP and SP pointing to different stacks, + * skipping the FP boundary check at this point. + */ + if (pc >= (unsigned long)&call_with_stack && + pc < (unsigned long)&call_with_stack_end) + return 0; /* only go to a higher address on the stack */ low = frame->sp; high = ALIGN(low, THREAD_SIZE); -#ifdef CONFIG_CC_IS_CLANG /* check current frame pointer is within bounds */ +#ifdef CONFIG_CC_IS_CLANG if (fp < low + 4 || fp > high - 4) return -EINVAL; - - frame->sp = frame->fp; - frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp)); - frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 4)); #else - /* check current frame pointer is within bounds */ if (fp < low + 12 || fp > high - 4) return -EINVAL; +#endif + + return 0; +} + +int notrace unwind_frame(struct stackframe *frame) +{ + unsigned long fp = frame->fp; + + if (frame_pointer_check(frame)) + return -EINVAL; /* restore the registers from the stack frame */ +#ifdef CONFIG_CC_IS_CLANG + frame->sp = frame->fp; + frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp)); + frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 4)); +#else frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp - 12)); frame->sp = READ_ONCE_NOCHECK(*(unsigned long *)(fp - 8)); frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp - 4)); diff --git a/arch/arm/lib/call_with_stack.S b/arch/arm/lib/call_with_stack.S index 0a268a6c513c..5030d4e8d126 100644 --- a/arch/arm/lib/call_with_stack.S +++ b/arch/arm/lib/call_with_stack.S @@ -46,4 +46,6 @@ UNWIND( .setfp fpreg, sp ) pop {fpreg, pc} UNWIND( .fnend ) #endif + .globl call_with_stack_end +call_with_stack_end: ENDPROC(call_with_stack) |