diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-02-18 09:40:16 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-02-18 09:40:16 -0800 |
commit | 10f4902173130fcbb02a69566fefab35fc5f1f30 (patch) | |
tree | 51a570111e11bcdbbeb1520ee231dd749690b2ae /kernel/trace | |
parent | a3b22b9f11d9fbc48b0291ea92259a5a810e9438 (diff) | |
parent | 9e7382153f80ba45a0bbcd540fb77d4b15f6e966 (diff) |
Merge tag 'trace-v5.0-rc4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two more tracing fixes
- Have kprobes not use copy_from_user() to access kernel addresses,
because kprobes can legitimately poke at bad kernel memory, which
will fault. Copy from user code should never fault in kernel space.
Using probe_mem_read() can handle kernel address space faulting.
- Put back the entries counter in the tracing output that was
accidentally removed"
* tag 'trace-v5.0-rc4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix number of entries in trace header
kprobe: Do not use uaccess functions to access kernel memory that can fault
Diffstat (limited to 'kernel/trace')
-rw-r--r-- | kernel/trace/trace.c | 2 | ||||
-rw-r--r-- | kernel/trace/trace_kprobe.c | 10 |
2 files changed, 3 insertions, 9 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index c521b7347482..c4238b441624 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3384,6 +3384,8 @@ static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file const char tgid_space[] = " "; const char space[] = " "; + print_event_info(buf, m); + seq_printf(m, "# %s _-----=> irqs-off\n", tgid ? tgid_space : space); seq_printf(m, "# %s / _----=> need-resched\n", diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index d5fb09ebba8b..9eaf07f99212 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -861,22 +861,14 @@ static const struct file_operations kprobe_profile_ops = { static nokprobe_inline int fetch_store_strlen(unsigned long addr) { - mm_segment_t old_fs; int ret, len = 0; u8 c; - old_fs = get_fs(); - set_fs(KERNEL_DS); - pagefault_disable(); - do { - ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); + ret = probe_mem_read(&c, (u8 *)addr + len, 1); len++; } while (c && ret == 0 && len < MAX_STRING_SIZE); - pagefault_enable(); - set_fs(old_fs); - return (ret < 0) ? ret : len; } |