diff options
| author | Masami Hiramatsu | 2020-10-15 23:55:25 +0900 |
|---|---|---|
| committer | Steven Rostedt (VMware) | 2021-02-11 16:31:57 -0500 |
| commit | a345a6718bd5689f7cff7715e902d8739e0d5beb (patch) | |
| tree | 5924d99849bd3cc4fc2072f69a46f377114cc807 /kernel/trace | |
| parent | 1600cbcf6944dee9f87f52cbceb0b6895c29efd0 (diff) | |
tracing: Add ptr-hash option to show the hashed pointer value
Add tracefs/options/hash-ptr option to show hashed pointer
value by %p in event printk format string.
For the security reason, normal printk will show the hashed
pointer value (encrypted by random number) with %p to printk
buffer to hide the real address. But the tracefs/trace always
shows real address for debug. To bridge those outputs, add an
option to switch the output format. Ftrace users can use it
to find the hashed value corresponding to the real address
in trace log.
Link: https://lkml.kernel.org/r/160277372504.29307.14909828808982012211.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace.c | 3 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 1 |
2 files changed, 4 insertions, 0 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 39f8a537196e..16e252d39016 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3558,6 +3558,9 @@ const char *trace_event_format(struct trace_iterator *iter, const char *fmt) if (WARN_ON_ONCE(!fmt)) return fmt; + if (iter->tr->trace_flags & TRACE_ITER_HASH_PTR) + return fmt; + p = fmt; new_fmt = q = iter->fmt; while (*p) { diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 6c3ea6f95e68..dec13ff66077 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1175,6 +1175,7 @@ extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, C(MARKERS, "markers"), \ C(EVENT_FORK, "event-fork"), \ C(PAUSE_ON_TRACE, "pause-on-trace"), \ + C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \ FUNCTION_FLAGS \ FGRAPH_FLAGS \ STACK_FLAGS \ |