FAILED: patch "[PATCH] tracing/probes: Fix to show a parse error for bad type for" failed to apply to 5.10-stable tree

The patch below does not apply to the 5.10-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 <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 8c427cc2fa73684ea140999e121b7b6c1c717632
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024021941-launch-unjustly-2fa8@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..

Possible dependencies:

8c427cc2fa73 ("tracing/probes: Fix to show a parse error for bad type for $comm") 27973e5c64b9 ("tracing/probes: Add string type check with BTF")
d157d7694460 ("tracing/probes: Support BTF field access from $retval")
c440adfbe302 ("tracing/probes: Support BTF based data structure field access") ebeed8d4a555 ("tracing/probes: Move finding func-proto API and getting func-param API to trace_btf") b1d1e90490b6 ("tracing/probes: Support BTF argument on module functions") 1f9f4f4777e7 ("tracing/probes: Fix to add NULL check for BTF APIs")
53431798f4bb ("tracing/probes: Fix tracepoint event with $arg* to fetch correct argument") fd26290ec89d ("tracing/probes: Add BTF retval type support")
18b1e870a496 ("tracing/probes: Add $arg* meta argument for all function args") b576e09701c7 ("tracing/probes: Support function parameters if BTF is available") 1b8b0cd754cd ("tracing/probes: Move event parameter fetching code to common parser") e2d0d7b2f42d ("tracing/probes: Add tracepoint support on fprobe_events") 334e5519c375 ("tracing/probes: Add fprobe events for tracing function entry and exit.") 30460c21ed40 ("tracing/probes: Avoid setting TPARG_FL_FENTRY and TPARG_FL_RETURN") d4505aa6afae ("tracing/probes: Reject symbol/symstr type for uprobe")
b26a124cbfa8 ("tracing/probes: Add symstr type for dynamic events")
61b304b73ab4 ("tracing/fprobe: Fix to check whether fprobe is registered correctly") 752be5c5c910 ("tracing/eprobe: Add eprobe filter support")
ab8384442ee5 ("tracing/probes: Have kprobes and uprobes use $COMM too")

thanks,

greg k-h

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

From 8c427cc2fa73684ea140999e121b7b6c1c717632 Mon Sep 17 00:00:00 2001
From: "Masami Hiramatsu (Google)" <[email protected]>
Date: Wed, 24 Jan 2024 00:02:34 +0900
Subject: [PATCH] tracing/probes: Fix to show a parse error for bad type for
$comm

Fix to show a parse error for bad type (non-string) for $comm/$COMM and immediate-string. With this fix, error_log file shows appropriate error message as below.

/sys/kernel/tracing # echo 'p vfs_read $comm:u32' >> kprobe_events
sh: write error: Invalid argument
/sys/kernel/tracing # echo 'p vfs_read \"hoge":u32' >> kprobe_events
sh: write error: Invalid argument
/sys/kernel/tracing # cat error_log

[   30.144183] trace_kprobe: error: $comm and immediate-string only accepts string type
  Command: p vfs_read $comm:u32
                            ^
[   62.618500] trace_kprobe: error: $comm and immediate-string only accepts string type
  Command: p vfs_read \"hoge":u32
                              ^

index 4dc74d73fc1d..c6da5923e5b9 100644
@@ -1159,9 +1159,12 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 	if (!(ctx->flags & TPARG_FL_TEVENT) &&
 	    (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")))
+		/* The type of $comm must be "string", and not an array type. */
+		if (parg->count || (t && strcmp(t, "string"))) {
+			trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0),
+					NEED_STRING_TYPE);
 			goto out;
+		}
 		parg->type = find_fetch_type("string", ctx->flags);
 	} else
 		parg->type = find_fetch_type(t, ctx->flags);

index 850d9ecb6765..c1877d018269 100644
@@ -515,7 +515,8 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
 	C(BAD_HYPHEN,		"Failed to parse single hyphen. Forgot '>'?"),	\
 	C(NO_BTF_FIELD,		"This field is not found."),	\
 	C(BAD_BTF_TID,		"Failed to get BTF type info."),\
-	C(BAD_TYPE4STR,		"This type does not fit for string."),
+	C(BAD_TYPE4STR,		"This type does not fit for string."),\
+	C(NEED_STRING_TYPE,	"$comm and immediate-string only accepts string type"),
 
 #undef C
 #define C(a, b)		TP_ERR_##a