diff options
Diffstat (limited to 'arch/powerpc/kernel/perf_callchain.c')
| -rw-r--r-- | arch/powerpc/kernel/perf_callchain.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/perf_callchain.c b/arch/powerpc/kernel/perf_callchain.c index d05ae42..e80026c 100644 --- a/arch/powerpc/kernel/perf_callchain.c +++ b/arch/powerpc/kernel/perf_callchain.c @@ -154,8 +154,12 @@ static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret) ((unsigned long)ptr & 7)) return -EFAULT; - if (!__get_user_inatomic(*ret, ptr)) + pagefault_disable(); + if (!__get_user_inatomic(*ret, ptr)) { + pagefault_enable(); return 0; + } + pagefault_enable(); return read_user_stack_slow(ptr, ret, 8); } @@ -166,8 +170,12 @@ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) ((unsigned long)ptr & 3)) return -EFAULT; - if (!__get_user_inatomic(*ret, ptr)) + pagefault_disable(); + if (!__get_user_inatomic(*ret, ptr)) { + pagefault_enable(); return 0; + } + pagefault_enable(); return read_user_stack_slow(ptr, ret, 4); } @@ -235,7 +243,7 @@ static void perf_callchain_user_64(struct perf_callchain_entry *entry, sp = regs->gpr[1]; perf_callchain_store(entry, next_ip); - for (;;) { + while (entry->nr < PERF_MAX_STACK_DEPTH) { fp = (unsigned long __user *) sp; if (!valid_user_sp(sp, 1) || read_user_stack_64(fp, &next_sp)) return; @@ -294,11 +302,17 @@ static inline int current_is_64bit(void) */ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) { + int rc; + if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) || ((unsigned long)ptr & 3)) return -EFAULT; - return __get_user_inatomic(*ret, ptr); + pagefault_disable(); + rc = __get_user_inatomic(*ret, ptr); + pagefault_enable(); + + return rc; } static inline void perf_callchain_user_64(struct perf_callchain_entry *entry, |