From 01573e231f18eb2d99162747186f59511f56b64d Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Fri, 08 Dec 2023 10:40:48 +0000
Subject: [PATCH] 移去rt
---
kernel/arch/x86/kernel/dumpstack.c | 119 ++++++++++++++++++++++++++++++++++++++++++++---------------
1 files changed, 88 insertions(+), 31 deletions(-)
diff --git a/kernel/arch/x86/kernel/dumpstack.c b/kernel/arch/x86/kernel/dumpstack.c
index 2b58864..97aa900 100644
--- a/kernel/arch/x86/kernel/dumpstack.c
+++ b/kernel/arch/x86/kernel/dumpstack.c
@@ -29,8 +29,8 @@
static struct pt_regs exec_summary_regs;
-bool in_task_stack(unsigned long *stack, struct task_struct *task,
- struct stack_info *info)
+bool noinstr in_task_stack(unsigned long *stack, struct task_struct *task,
+ struct stack_info *info)
{
unsigned long *begin = task_stack_page(task);
unsigned long *end = task_stack_page(task) + THREAD_SIZE;
@@ -46,7 +46,8 @@
return true;
}
-bool in_entry_stack(unsigned long *stack, struct stack_info *info)
+/* Called from get_stack_info_noinstr - so must be noinstr too */
+bool noinstr in_entry_stack(unsigned long *stack, struct stack_info *info)
{
struct entry_stack *ss = cpu_entry_stack(smp_processor_id());
@@ -65,10 +66,35 @@
}
static void printk_stack_address(unsigned long address, int reliable,
- char *log_lvl)
+ const char *log_lvl)
{
touch_nmi_watchdog();
printk("%s %s%pB\n", log_lvl, reliable ? "" : "? ", (void *)address);
+}
+
+static int copy_code(struct pt_regs *regs, u8 *buf, unsigned long src,
+ unsigned int nbytes)
+{
+ if (!user_mode(regs))
+ return copy_from_kernel_nofault(buf, (u8 *)src, nbytes);
+
+ /* The user space code from other tasks cannot be accessed. */
+ if (regs != task_pt_regs(current))
+ return -EPERM;
+ /*
+ * Make sure userspace isn't trying to trick us into dumping kernel
+ * memory by pointing the userspace instruction pointer at it.
+ */
+ if (__chk_range_not_ok(src, nbytes, TASK_SIZE_MAX))
+ return -EINVAL;
+
+ /*
+ * Even if named copy_from_user_nmi() this can be invoked from
+ * other contexts and will not try to resolve a pagefault, which is
+ * the correct thing to do here as this code can be called from any
+ * context.
+ */
+ return copy_from_user_nmi(buf, (void __user *)src, nbytes);
}
/*
@@ -97,22 +123,20 @@
#define OPCODE_BUFSIZE (PROLOGUE_SIZE + 1 + EPILOGUE_SIZE)
u8 opcodes[OPCODE_BUFSIZE];
unsigned long prologue = regs->ip - PROLOGUE_SIZE;
- bool bad_ip;
- /*
- * Make sure userspace isn't trying to trick us into dumping kernel
- * memory by pointing the userspace instruction pointer at it.
- */
- bad_ip = user_mode(regs) &&
- __chk_range_not_ok(prologue, OPCODE_BUFSIZE, TASK_SIZE_MAX);
-
- if (bad_ip || probe_kernel_read(opcodes, (u8 *)prologue,
- OPCODE_BUFSIZE)) {
- printk("%sCode: Bad RIP value.\n", loglvl);
- } else {
+ switch (copy_code(regs, opcodes, prologue, sizeof(opcodes))) {
+ case 0:
printk("%sCode: %" __stringify(PROLOGUE_SIZE) "ph <%02x> %"
__stringify(EPILOGUE_SIZE) "ph\n", loglvl, opcodes,
opcodes[PROLOGUE_SIZE], opcodes + PROLOGUE_SIZE + 1);
+ break;
+ case -EPERM:
+ /* No access to the user space stack of other tasks. Ignore. */
+ break;
+ default:
+ printk("%sCode: Unable to access opcode bytes at RIP 0x%lx.\n",
+ loglvl, prologue);
+ break;
}
}
@@ -126,15 +150,15 @@
show_opcodes(regs, loglvl);
}
-void show_iret_regs(struct pt_regs *regs)
+void show_iret_regs(struct pt_regs *regs, const char *log_lvl)
{
- show_ip(regs, KERN_DEFAULT);
- printk(KERN_DEFAULT "RSP: %04x:%016lx EFLAGS: %08lx", (int)regs->ss,
+ show_ip(regs, log_lvl);
+ printk("%sRSP: %04x:%016lx EFLAGS: %08lx", log_lvl, (int)regs->ss,
regs->sp, regs->flags);
}
static void show_regs_if_on_stack(struct stack_info *info, struct pt_regs *regs,
- bool partial)
+ bool partial, const char *log_lvl)
{
/*
* These on_stack() checks aren't strictly necessary: the unwind code
@@ -146,7 +170,7 @@
* they can be printed in the right context.
*/
if (!partial && on_stack(info, regs, sizeof(*regs))) {
- __show_regs(regs, SHOW_REGS_SHORT);
+ __show_regs(regs, SHOW_REGS_SHORT, log_lvl);
} else if (partial && on_stack(info, (void *)regs + IRET_FRAME_OFFSET,
IRET_FRAME_SIZE)) {
@@ -155,12 +179,12 @@
* full pt_regs might not have been saved yet. In that case
* just print the iret frame.
*/
- show_iret_regs(regs);
+ show_iret_regs(regs, log_lvl);
}
}
void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
- unsigned long *stack, char *log_lvl)
+ unsigned long *stack, const char *log_lvl)
{
struct unwind_state state;
struct stack_info stack_info = {0};
@@ -210,7 +234,7 @@
printk("%s <%s>\n", log_lvl, stack_name);
if (regs)
- show_regs_if_on_stack(&stack_info, regs, partial);
+ show_regs_if_on_stack(&stack_info, regs, partial, log_lvl);
/*
* Scan the stack, printing any text addresses we find. At the
@@ -271,7 +295,7 @@
/* if the frame has entry regs, print them */
regs = unwind_get_entry_regs(&state, &partial);
if (regs)
- show_regs_if_on_stack(&stack_info, regs, partial);
+ show_regs_if_on_stack(&stack_info, regs, partial, log_lvl);
}
if (stack_name)
@@ -279,7 +303,8 @@
}
}
-void show_stack(struct task_struct *task, unsigned long *sp)
+void show_stack(struct task_struct *task, unsigned long *sp,
+ const char *loglvl)
{
task = task ? : current;
@@ -290,7 +315,7 @@
if (!sp && task == current)
sp = get_stack_pointer(current, NULL);
- show_trace_log_lvl(task, NULL, sp, KERN_DEFAULT);
+ show_trace_log_lvl(task, NULL, sp, loglvl);
}
void show_stack_regs(struct pt_regs *regs)
@@ -344,7 +369,7 @@
oops_exit();
/* Executive summary in case the oops scrolled away */
- __show_regs(&exec_summary_regs, SHOW_REGS_ALL);
+ __show_regs(&exec_summary_regs, SHOW_REGS_ALL, KERN_DEFAULT);
if (!signr)
return;
@@ -365,21 +390,30 @@
}
NOKPROBE_SYMBOL(oops_end);
-int __die(const char *str, struct pt_regs *regs, long err)
+static void __die_header(const char *str, struct pt_regs *regs, long err)
{
+ const char *pr = "";
+
/* Save the regs of the first oops for the executive summary later. */
if (!die_counter)
exec_summary_regs = *regs;
+ if (IS_ENABLED(CONFIG_PREEMPTION))
+ pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
+
printk(KERN_DEFAULT
"%s: %04lx [#%d]%s%s%s%s%s\n", str, err & 0xffff, ++die_counter,
- IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
+ pr,
IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
IS_ENABLED(CONFIG_KASAN) ? " KASAN" : "",
IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION) ?
(boot_cpu_has(X86_FEATURE_PTI) ? " PTI" : " NOPTI") : "");
+}
+NOKPROBE_SYMBOL(__die_header);
+static int __die_body(const char *str, struct pt_regs *regs, long err)
+{
show_regs(regs);
print_modules();
@@ -388,6 +422,13 @@
return 1;
return 0;
+}
+NOKPROBE_SYMBOL(__die_body);
+
+int __die(const char *str, struct pt_regs *regs, long err)
+{
+ __die_header(str, regs, err);
+ return __die_body(str, regs, err);
}
NOKPROBE_SYMBOL(__die);
@@ -405,11 +446,27 @@
oops_end(flags, regs, sig);
}
+void die_addr(const char *str, struct pt_regs *regs, long err, long gp_addr)
+{
+ unsigned long flags = oops_begin();
+ int sig = SIGSEGV;
+
+ __die_header(str, regs, err);
+ if (gp_addr)
+ kasan_non_canonical_hook(gp_addr);
+ if (__die_body(str, regs, err))
+ sig = 0;
+ oops_end(flags, regs, sig);
+}
+
void show_regs(struct pt_regs *regs)
{
+ enum show_regs_mode print_kernel_regs;
+
show_regs_print_info(KERN_DEFAULT);
- __show_regs(regs, user_mode(regs) ? SHOW_REGS_USER : SHOW_REGS_ALL);
+ print_kernel_regs = user_mode(regs) ? SHOW_REGS_USER : SHOW_REGS_ALL;
+ __show_regs(regs, print_kernel_regs, KERN_DEFAULT);
/*
* When in-kernel, we also print out the stack at the time of the fault..
--
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