[RFC PATCH v2 3/8] arm64: Terminate the stack trace at TASK_FRAME and EL0_FRAME
From: <hidden>
Date: 2021-03-15 16:59:20
Also in:
linux-arm-kernel, lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
From: "Madhavan T. Venkataraman" <redacted> Implement the following checks in the unwinder to detect the terminating frame reliably: - The frame must end in task_pt_regs(task)->stackframe. - The frame type must be either TASK_FRAME or EL0_FRAME. Signed-off-by: Madhavan T. Venkataraman <redacted> --- arch/arm64/kernel/stacktrace.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index ad20981dfda4..504cd161339d 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c@@ -43,16 +43,22 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) { unsigned long fp = frame->fp; struct stack_info info; + struct pt_regs *regs; - /* Terminal record; nothing to unwind */ - if (!fp) - return -ENOENT; + if (!tsk) + tsk = current; + regs = task_pt_regs(tsk); - if (fp & 0xf) + /* Terminal record, nothing to unwind */ + if (fp == (unsigned long) regs->stackframe) { + if (regs->frame_type == TASK_FRAME || + regs->frame_type == EL0_FRAME) + return -ENOENT; return -EINVAL; + } - if (!tsk) - tsk = current; + if (!fp || fp & 0xf) + return -EINVAL; if (!on_accessible_stack(tsk, fp, &info)) return -EINVAL;
--
2.25.1