FAILED: patch "[PATCH] tracing/probes: Have kprobes and uprobes use $COMM too" failed to apply to 4.19-stable tree

FAILED: patch "[PATCH] tracing/probes: Have kprobes and uprobes use $COMM too" failed to apply to 4.19-stable tree

[gregkh]

The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From ab8384442ee512fc0fc72deeb036110843d0e7ff Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
Date: Sat, 20 Aug 2022 09:43:21 -0400
Subject: [PATCH] tracing/probes: Have kprobes and uprobes use $COMM too

Both $comm and $COMM can be used to get current->comm in eprobes and the
filtering and histogram logic. Make kprobes and uprobes consistent in this
regard and allow both $comm and $COMM as well. Currently kprobes and
uprobes only handle $comm, which is inconsistent with the other utilities,
and can be confusing to users.

Link: https://lkml.kernel.org/r/20220820134401.317014913@goodmis.org
Link: https://lore.kernel.org/all/20220820220442.776e1ddaf8836e82edb34d01@kernel.org/

Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Fixes: 533059281ee5 ("tracing: probeevent: Introduce new argument fetching code")
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 4daabbb8b772..36dff277de46 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -314,7 +314,7 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t,
 			}
 		} else
 			goto inval_var;
-	} else if (strcmp(arg, "comm") == 0) {
+	} else if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) {
 		code->op = FETCH_OP_COMM;
 #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
 	} else if (((flags & TPARG_FL_MASK) ==
@@ -625,7 +625,8 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 	 * we can find those by strcmp. But ignore for eprobes.
 	 */
 	if (!(flags & TPARG_FL_TPOINT) &&
-	    (strcmp(arg, "$comm") == 0 || strncmp(arg, "\\\"", 2) == 0)) {
+	    (strcmp(arg, "$comm") == 0 || strcmp(arg, "$COMM") == 0 ||
+	     strncmp(arg, "\\\"", 2) == 0)) {
 		/* The type of $comm must be "string", and not an array. */
 		if (parg->count || (t && strcmp(t, "string")))
 			goto out;

Re: FAILED: patch "[PATCH] tracing/probes: Have kprobes and uprobes use $COMM too" failed to apply to 4.19-stable tree

[Steven Rostedt]

This is the backport for 4.19.

-- Steve

------------------ original commit in Linus's tree ------------------

>From ab8384442ee512fc0fc72deeb036110843d0e7ff Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
Date: Sat, 20 Aug 2022 09:43:21 -0400
Subject: [PATCH] tracing/probes: Have kprobes and uprobes use $COMM too

Both $comm and $COMM can be used to get current->comm in eprobes and the
filtering and histogram logic. Make kprobes and uprobes consistent in this
regard and allow both $comm and $COMM as well. Currently kprobes and
uprobes only handle $comm, which is inconsistent with the other utilities,
and can be confusing to users.

Link: https://lkml.kernel.org/r/20220820134401.317014913@goodmis.org
Link: https://lore.kernel.org/all/20220820220442.776e1ddaf8836e82edb34d01@kernel.org/

Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Fixes: 533059281ee5 ("tracing: probeevent: Introduce new argument fetching code")
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

---
 kernel/trace/trace_probe.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Index: linux-test.git/kernel/trace/trace_probe.c
===================================================================
--- linux-test.git.orig/kernel/trace/trace_probe.c	2022-08-22 12:13:58.964843406 -0400
+++ linux-test.git/kernel/trace/trace_probe.c	2022-08-22 12:15:44.808843824 -0400
@@ -361,7 +361,7 @@ static int parse_probe_vars(char *arg, c
 			}
 		} else
 			ret = -EINVAL;
-	} else if (strcmp(arg, "comm") == 0) {
+	} else if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) {
 		if (strcmp(t->name, "string") != 0 &&
 		    strcmp(t->name, "string_size") != 0)
 			return -EINVAL;
@@ -544,7 +544,7 @@ int traceprobe_parse_probe_arg(char *arg
 	 * The default type of $comm should be "string", and it can't be
 	 * dereferenced.
 	 */
-	if (!t && strcmp(arg, "$comm") == 0)
+	if (!t && (strcmp(arg, "$comm") == 0 || strcmp(arg, "$COMM") == 0))
 		t = "string";
 	parg->type = find_fetch_type(t, ftbl);
 	if (!parg->type) {

Re: FAILED: patch "[PATCH] tracing/probes: Have kprobes and uprobes use $COMM too" failed to apply to 4.19-stable tree

[Greg KH]

On Mon, Aug 22, 2022 at 12:37:27PM -0400, Steven Rostedt wrote:
> 
> This is the backport for 4.19.

All backports now queued up, thanks.

greg k-h