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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-18 09:30:18 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-18 09:30:18 -0700
commitb75d3886f34e194780239231aa973b283afa9a3a (patch)
tree0359727dc83d60c9c546b225a3f912e03dfab896 /arch/x86
parente0ed1c22d480a3b5ec5fce4e5399cf4481da95a6 (diff)
parent0130669966bf337b616d559d5405614c0a4ae313 (diff)
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar: "Four tooling fixes, two kprobes KASAN related fixes and an x86 PMU driver fix/cleanup" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf jit: Fix build issue on Ubuntu perf jevents: Handle events including .c and .o perf/x86/intel: Remove an inconsistent NULL check kprobes: Unpoison stack in jprobe_return() for KASAN kprobes: Avoid false KASAN reports during stack copy perf header: Set nr_numa_nodes only when we parsed all the data perf top: Fix refreshing hierarchy entries on TUI
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/events/intel/lbr.c4
-rw-r--r--arch/x86/kernel/kprobes/core.c11
2 files changed, 10 insertions, 5 deletions
diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c
index fc6cf21c535e..81b321ace8e0 100644
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -458,8 +458,8 @@ void intel_pmu_lbr_del(struct perf_event *event)
if (!x86_pmu.lbr_nr)
return;
- if (branch_user_callstack(cpuc->br_sel) && event->ctx &&
- event->ctx->task_ctx_data) {
+ if (branch_user_callstack(cpuc->br_sel) &&
+ event->ctx->task_ctx_data) {
task_ctx = event->ctx->task_ctx_data;
task_ctx->lbr_callstack_users--;
}
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;
}