diff options
author | Li Huafei <lihuafei1@huawei.com> | 2022-08-26 09:06:22 +0100 |
---|---|---|
committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-10-04 11:09:47 +0100 |
commit | 5854e4d8530e6ed4c2532a71a6b0474e199d44dd (patch) | |
tree | 459e56c09936983f81f6f3f029dab44a4820d791 | |
parent | 09cffecaa7703fd4c54b25f6c21c3a93e87c2e8f (diff) | |
download | linux-5854e4d8530e6ed4c2532a71a6b0474e199d44dd.tar.bz2 |
ARM: 9233/1: stacktrace: Skip frame pointer boundary check for call_with_stack()
When using the frame pointer unwinder, it was found that the stack trace
output of stack_trace_save() is incomplete if the stack contains
call_with_stack():
[0x7f00002c] dump_stack_task+0x2c/0x90 [hrtimer]
[0x7f0000a0] hrtimer_hander+0x10/0x18 [hrtimer]
[0x801a67f0] __hrtimer_run_queues+0x1b0/0x3b4
[0x801a7350] hrtimer_run_queues+0xc4/0xd8
[0x801a597c] update_process_times+0x3c/0x88
[0x801b5a98] tick_periodic+0x50/0xd8
[0x801b5bf4] tick_handle_periodic+0x24/0x84
[0x8010ffc4] twd_handler+0x38/0x48
[0x8017d220] handle_percpu_devid_irq+0xa8/0x244
[0x80176e9c] generic_handle_domain_irq+0x2c/0x3c
[0x8052e3a8] gic_handle_irq+0x7c/0x90
[0x808ab15c] generic_handle_arch_irq+0x60/0x80
[0x8051191c] call_with_stack+0x1c/0x20
For the frame pointer unwinder, unwind_frame() checks stackframe::fp by
stackframe::sp. Since call_with_stack() switches the SP from one stack
to another, stackframe::fp and stackframe: :sp will point to different
stacks, so we can no longer check stackframe::fp by stackframe::sp. Skip
checking stackframe::fp at this point to avoid this problem.
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Reviewed-by: Linus Waleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
-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) |