Patch "tracing/kprobes: Allow to create probe with a module name starting with a digit" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

tracing/kprobes: Allow to create probe with a module name starting with a digit

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
tracing-kprobes-allow-to-create-probe-with-a-module-name-starting-with-a-digit.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Sabrina Dubroca <[email protected]>
Date: Thu, 22 Jun 2017 11:24:42 +0200
Subject: tracing/kprobes: Allow to create probe with a module name starting with a digit

From: Sabrina Dubroca <[email protected]>

commit 9e52b32567126fe146f198971364f68d3bc5233f upstream.

Always try to parse an address, since kstrtoul() will safely fail when given a symbol as input. If that fails (which will be the case for a symbol), try to parse a symbol instead.

This allows creating a probe such as:

    p:probe/vlan_gro_receive 8021q:vlan_gro_receive+0

Which is necessary for this command to work:

perf probe -m 8021q -a vlan_gro_receive

---
 kernel/trace/trace_kprobe.c |   21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

@@ -667,30 +667,25 @@ static int create_trace_kprobe(int argc,
 		pr_info("Probe point is not specified.\n");
 		return -EINVAL;
 	}
-	if (isdigit(argv[1][0])) {
-		if (is_return) {
-			pr_info("Return probe point must be a symbol.\n");
-			return -EINVAL;
-		}
-		/* an address specified */
-		ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr);
-		if (ret) {
-			pr_info("Failed to parse address.\n");
-			return ret;
-		}
-	} else {
+
+	/* try to parse an address. if that fails, try to read the
+	 * input as a symbol. */
+	if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) {
 		/* a symbol specified */
 		symbol = argv[1];
 		/* TODO: support .init module functions */
 		ret = traceprobe_split_symbol_offset(symbol, &offset);
 		if (ret) {
-			pr_info("Failed to parse symbol.\n");
+			pr_info("Failed to parse either an address or a symbol.\n");
 			return ret;
 		}
 		if (offset && is_return) {
 			pr_info("Return probe must be used without offset.\n");
 			return -EINVAL;
 		}
+	} else if (is_return) {
+		pr_info("Return probe point must be a symbol.\n");
+		return -EINVAL;
 	}
 	argc -= 2; argv += 2;
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/tracing-kprobes-allow-to-create-probe-with-a-module-name-starting-with-a-digit.patch