X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fkprobes%2Fcore.c;h=d9d8d16b69db89df63b5ff33a4e597fcf4e5eba6;hb=0ea67fae9e80bfd69713b51ba3fa53879be5383b;hp=28cee019209ce7f7fd9ec160e4409fecf000819f;hpb=d8bfb96a2e3c42f91a9944a19638c043cb86dd8f;p=cascardo%2Flinux.git

diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 28cee019209c..d9d8d16b69db 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -50,6 +50,7 @@
 #include <linux/kallsyms.h>
 #include <linux/ftrace.h>
 #include <linux/frame.h>
+#include <linux/kasan.h>
 
 #include <asm/text-patching.h>
 #include <asm/cacheflush.h>
@@ -1057,9 +1058,10 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
 	 * tailcall optimization. So, to be absolutely safe
 	 * we also save and restore enough stack bytes to cover
 	 * the argument area.
+	 * Use __memcpy() to avoid KASAN stack out-of-bounds reports as we copy
+	 * raw stack chunk with redzones:
 	 */
-	memcpy(kcb->jprobes_stack, (kprobe_opcode_t *)addr,
-	       MIN_STACK_SIZE(addr));
+	__memcpy(kcb->jprobes_stack, (kprobe_opcode_t *)addr, MIN_STACK_SIZE(addr));
 	regs->flags &= ~X86_EFLAGS_IF;
 	trace_hardirqs_off();
 	regs->ip = (unsigned long)(jp->entry);
@@ -1080,6 +1082,9 @@ void jprobe_return(void)
 {
 	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
 
+	/* Unpoison stack redzones in the frames we are going to jump over. */
+	kasan_unpoison_stack_above_sp_to(kcb->jprobe_saved_sp);
+
 	asm volatile (
 #ifdef CONFIG_X86_64
 			"       xchg   %%rbx,%%rsp	\n"
@@ -1118,7 +1123,7 @@ int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
 		/* It's OK to start function graph tracing again */
 		unpause_graph_tracing();
 		*regs = kcb->jprobe_saved_regs;
-		memcpy(saved_sp, kcb->jprobes_stack, MIN_STACK_SIZE(saved_sp));
+		__memcpy(saved_sp, kcb->jprobes_stack, MIN_STACK_SIZE(saved_sp));
 		preempt_enable_no_resched();
 		return 1;
 	}