diff options
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event.c | 44 | ||||
| -rw-r--r-- | arch/x86/kernel/dumpstack.h | 5 |
2 files changed, 44 insertions, 5 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index bd28cf9d8a82..53ea4cf1a878 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -28,6 +28,7 @@ #include <asm/apic.h> #include <asm/stacktrace.h> #include <asm/nmi.h> +#include <asm/compat.h> static u64 perf_event_mask __read_mostly; @@ -1630,14 +1631,42 @@ copy_from_user_nmi(void *to, const void __user *from, unsigned long n) return len; } -static int copy_stack_frame(const void __user *fp, struct stack_frame *frame) +#ifdef CONFIG_COMPAT +static inline int +perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry) { - unsigned long bytes; + /* 32-bit process in 64-bit kernel. */ + struct stack_frame_ia32 frame; + const void __user *fp; + + if (!test_thread_flag(TIF_IA32)) + return 0; + + fp = compat_ptr(regs->bp); + while (entry->nr < PERF_MAX_STACK_DEPTH) { + unsigned long bytes; + frame.next_frame = 0; + frame.return_address = 0; - bytes = copy_from_user_nmi(frame, fp, sizeof(*frame)); + bytes = copy_from_user_nmi(&frame, fp, sizeof(frame)); + if (bytes != sizeof(frame)) + break; + + if (fp < compat_ptr(regs->sp)) + break; - return bytes == sizeof(*frame); + callchain_store(entry, frame.return_address); + fp = compat_ptr(frame.next_frame); + } + return 1; } +#else +static inline int +perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry) +{ + return 0; +} +#endif static void perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry) @@ -1653,11 +1682,16 @@ perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry) callchain_store(entry, PERF_CONTEXT_USER); callchain_store(entry, regs->ip); + if (perf_callchain_user32(regs, entry)) + return; + while (entry->nr < PERF_MAX_STACK_DEPTH) { + unsigned long bytes; frame.next_frame = NULL; frame.return_address = 0; - if (!copy_stack_frame(fp, &frame)) + bytes = copy_from_user_nmi(&frame, fp, sizeof(frame)); + if (bytes != sizeof(frame)) break; if ((unsigned long)fp < regs->sp) diff --git a/arch/x86/kernel/dumpstack.h b/arch/x86/kernel/dumpstack.h index 29e5f7c845b2..e39e77168a37 100644 --- a/arch/x86/kernel/dumpstack.h +++ b/arch/x86/kernel/dumpstack.h @@ -30,6 +30,11 @@ struct stack_frame { unsigned long return_address; }; +struct stack_frame_ia32 { + u32 next_frame; + u32 return_address; +}; + static inline unsigned long rewind_frame_pointer(int n) { struct stack_frame *frame; |