From: Masami Hiramatsu <mhiramat@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Andreas Ziegler <andreas.ziegler@fau.de>,
Masami Hiramatsu <mhiramat@kernel.org>,
Ingo Molnar <mingo@redhat.com>,
linux-kernel@vger.kernel.org
Subject: [PATCH v2 3/3] tracing: probeevent: Fix to make the type of $comm string
Date: Fri, 18 Jan 2019 13:45:22 +0900 [thread overview]
Message-ID: <154778672210.19927.871647535916796323.stgit@devbox> (raw)
In-Reply-To: <154778663676.19927.12774448308165809570.stgit@devbox>
Fix to make the type of $comm "string".
If we set the other type to $comm argument, it shows
meaningless value or wrong data. Currently probe events
allow us to set string array type (e.g. ":string[2]"), or
other digit types like x8 on $comm. But since clearly
$comm is just a string data, it should not be fetched
by other types including array.
Fixes: 35abb67de744 ("tracing: expose current->comm to [ku]probe events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
---
kernel/trace/trace_probe.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 9962cb5da8ac..44f078cda0ac 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -405,13 +405,14 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
return -E2BIG;
}
}
- /*
- * The default type of $comm should be "string", and it can't be
- * dereferenced.
- */
- if (!t && strcmp(arg, "$comm") == 0)
+
+ /* Since $comm can not be dereferred, we can find $comm by strcmp */
+ if (strcmp(arg, "$comm") == 0) {
+ /* The type of $comm must be "string", and not an array. */
+ if (parg->count || (t && strcmp(t, "string")))
+ return -EINVAL;
parg->type = find_fetch_type("string");
- else
+ } else
parg->type = find_fetch_type(t);
if (!parg->type) {
pr_info("Unsupported type: %s\n", t);
prev parent reply other threads:[~2019-01-18 4:45 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-18 4:43 [PATCH v2 0/3] tracing: probeevent: Fix probe argument parser and handler Masami Hiramatsu
2019-01-18 4:44 ` [PATCH v2 1/3] tracing: uprobes: Re-enable $comm support for uprobe events Masami Hiramatsu
2019-01-23 8:40 ` Steven Rostedt
2019-01-24 1:43 ` Masami Hiramatsu
2019-01-24 2:09 ` Steven Rostedt
2019-01-24 3:03 ` Masami Hiramatsu
2019-02-06 20:52 ` Steven Rostedt
2019-02-08 0:42 ` Masami Hiramatsu
2019-01-18 4:44 ` [PATCH v2 2/3] tracing: probeevent: Do not accumulate on ret variable Masami Hiramatsu
2019-01-18 4:45 ` Masami Hiramatsu [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=154778672210.19927.871647535916796323.stgit@devbox \
--to=mhiramat@kernel.org \
--cc=andreas.ziegler@fau.de \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=rostedt@goodmis.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).