summaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/stacktrace.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/kernel/stacktrace.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kernel/stacktrace.c')
-rw-r--r--arch/x86/kernel/stacktrace.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
new file mode 100644
index 0000000000..ee117fcf46
--- /dev/null
+++ b/arch/x86/kernel/stacktrace.c
@@ -0,0 +1,130 @@
+/*
+ * Stack trace management functions
+ *
+ * Copyright (C) 2006-2009 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ */
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/stacktrace.h>
+#include <linux/export.h>
+#include <linux/uaccess.h>
+#include <asm/stacktrace.h>
+#include <asm/unwind.h>
+
+void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
+ struct task_struct *task, struct pt_regs *regs)
+{
+ struct unwind_state state;
+ unsigned long addr;
+
+ if (regs && !consume_entry(cookie, regs->ip))
+ return;
+
+ for (unwind_start(&state, task, regs, NULL); !unwind_done(&state);
+ unwind_next_frame(&state)) {
+ addr = unwind_get_return_address(&state);
+ if (!addr || !consume_entry(cookie, addr))
+ break;
+ }
+}
+
+int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry,
+ void *cookie, struct task_struct *task)
+{
+ struct unwind_state state;
+ struct pt_regs *regs;
+ unsigned long addr;
+
+ for (unwind_start(&state, task, NULL, NULL);
+ !unwind_done(&state) && !unwind_error(&state);
+ unwind_next_frame(&state)) {
+
+ regs = unwind_get_entry_regs(&state, NULL);
+ if (regs) {
+ /* Success path for user tasks */
+ if (user_mode(regs))
+ return 0;
+
+ /*
+ * Kernel mode registers on the stack indicate an
+ * in-kernel interrupt or exception (e.g., preemption
+ * or a page fault), which can make frame pointers
+ * unreliable.
+ */
+ if (IS_ENABLED(CONFIG_FRAME_POINTER))
+ return -EINVAL;
+ }
+
+ addr = unwind_get_return_address(&state);
+
+ /*
+ * A NULL or invalid return address probably means there's some
+ * generated code which __kernel_text_address() doesn't know
+ * about.
+ */
+ if (!addr)
+ return -EINVAL;
+
+ if (!consume_entry(cookie, addr))
+ return -EINVAL;
+ }
+
+ /* Check for stack corruption */
+ if (unwind_error(&state))
+ return -EINVAL;
+
+ return 0;
+}
+
+/* Userspace stacktrace - based on kernel/trace/trace_sysprof.c */
+
+struct stack_frame_user {
+ const void __user *next_fp;
+ unsigned long ret_addr;
+};
+
+static int
+copy_stack_frame(const struct stack_frame_user __user *fp,
+ struct stack_frame_user *frame)
+{
+ int ret;
+
+ if (!__access_ok(fp, sizeof(*frame)))
+ return 0;
+
+ ret = 1;
+ pagefault_disable();
+ if (__get_user(frame->next_fp, &fp->next_fp) ||
+ __get_user(frame->ret_addr, &fp->ret_addr))
+ ret = 0;
+ pagefault_enable();
+
+ return ret;
+}
+
+void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
+ const struct pt_regs *regs)
+{
+ const void __user *fp = (const void __user *)regs->bp;
+
+ if (!consume_entry(cookie, regs->ip))
+ return;
+
+ while (1) {
+ struct stack_frame_user frame;
+
+ frame.next_fp = NULL;
+ frame.ret_addr = 0;
+ if (!copy_stack_frame(fp, &frame))
+ break;
+ if ((unsigned long)fp < regs->sp)
+ break;
+ if (!frame.ret_addr)
+ break;
+ if (!consume_entry(cookie, frame.ret_addr))
+ break;
+ fp = frame.next_fp;
+ }
+}
+