2023-06-07 03:37:41 +00:00
|
|
|
From 9868ebc8e648e5791764a51567a23efae7170d9b Mon Sep 17 00:00:00 2001
|
|
|
|
|
From: HATAYAMA Daisuke <d.hatayama@fujitsu.com>
|
|
|
|
|
Date: Tue, 30 May 2023 19:38:35 +0900
|
2023-09-11 08:55:01 +00:00
|
|
|
Subject: [PATCH 06/30] Fix segfault in arm64_is_kernel_exception_frame() when
|
2023-06-07 03:37:41 +00:00
|
|
|
corrupt stack pointer address is given
|
|
|
|
|
|
|
|
|
|
Due to the corrupted mapping fixed by the previous commit,
|
|
|
|
|
arm64_is_kernel_exception_frame() can receive invalid stack pointer
|
|
|
|
|
address via the 2nd argument; different NT_PRSTATUS contains different
|
|
|
|
|
task's stack pointer address. However, macro STACK_OFFSET_TYPE() never
|
|
|
|
|
checks if a given address is within the range of the kernel stack of
|
|
|
|
|
the corresponding task and hence can result in referring to outside of
|
|
|
|
|
bt->stackbuf.
|
|
|
|
|
|
|
|
|
|
static int
|
|
|
|
|
arm64_is_kernel_exception_frame(struct bt_info *bt, ulong stkptr)
|
|
|
|
|
{
|
|
|
|
|
struct arm64_pt_regs *regs;
|
|
|
|
|
struct machine_specific *ms = machdep->machspec;
|
|
|
|
|
|
|
|
|
|
regs = (struct arm64_pt_regs *)&bt->stackbuf[(ulong)(STACK_OFFSET_TYPE(stkptr))];
|
|
|
|
|
|
|
|
|
|
=> if (INSTACK(regs->sp, bt) && INSTACK(regs->regs[29], bt) &&
|
|
|
|
|
!(regs->pstate & (0xffffffff00000000ULL | PSR_MODE32_BIT)) &&
|
|
|
|
|
is_kernel_text(regs->pc) &&
|
|
|
|
|
is_kernel_text(regs->regs[30] | ms->CONFIG_ARM64_KERNELPACMASK)) {
|
|
|
|
|
|
|
|
|
|
To fix this issue, check if the given stack pointer address points to
|
|
|
|
|
the range of the kernel stack of the corresponding task, and abort if
|
|
|
|
|
it turns out to be invalid.
|
|
|
|
|
|
|
|
|
|
Although the corrupted mapping has already been fixed, this fix is
|
|
|
|
|
still needed because corrupt stack pointer address can still be passed
|
|
|
|
|
here from different reasons. Consider, for example, that data on the
|
|
|
|
|
kernel stack can be modified abnormally due to any kernel bugs or
|
|
|
|
|
hardware issues.
|
|
|
|
|
|
|
|
|
|
Signed-off-by: HATAYAMA Daisuke <d.hatayama@fujitsu.com>
|
|
|
|
|
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
|
|
|
|
|
---
|
|
|
|
|
defs.h | 5 ++++-
|
|
|
|
|
1 file changed, 4 insertions(+), 1 deletion(-)
|
|
|
|
|
|
|
|
|
|
diff --git a/defs.h b/defs.h
|
|
|
|
|
index 6520d2f13f48..11fdc17e60d0 100644
|
|
|
|
|
--- a/defs.h
|
|
|
|
|
+++ b/defs.h
|
|
|
|
|
@@ -976,7 +976,10 @@ struct bt_info {
|
|
|
|
|
|
|
|
|
|
#define STACK_OFFSET_TYPE(OFF) \
|
|
|
|
|
(((ulong)(OFF) > STACKSIZE()) ? \
|
|
|
|
|
- (ulong)((ulong)(OFF) - (ulong)(bt->stackbase)) : (ulong)(OFF))
|
|
|
|
|
+ (((ulong)(OFF) < (ulong)(bt->stackbase) || (ulong)(OFF) >= (ulong)(bt->stackbase) + STACKSIZE()) ? \
|
|
|
|
|
+ error(FATAL, "invalid stack pointer is given\n") : \
|
|
|
|
|
+ (ulong)((ulong)(OFF) - (ulong)(bt->stackbase))) : \
|
|
|
|
|
+ (ulong)(OFF))
|
|
|
|
|
|
|
|
|
|
#define GET_STACK_ULONG(OFF) \
|
|
|
|
|
*((ulong *)((char *)(&bt->stackbuf[(ulong)(STACK_OFFSET_TYPE(OFF))])))
|
|
|
|
|
--
|
|
|
|
|
2.37.1
|
|
|
|
|
|
