lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20200129143829.509193973@goodmis.org>
Date:   Wed, 29 Jan 2020 09:38:04 -0500
From:   Steven Rostedt <rostedt@...dmis.org>
To:     linux-kernel@...r.kernel.org
Cc:     Ingo Molnar <mingo@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Tom Zanussi <zanussi@...nel.org>
Subject: [for-next][PATCH 2/5] tracing: Simplify assignment parsing for hist triggers

From: Tom Zanussi <zanussi@...nel.org>

In the process of adding better error messages for sorting, I realized
that strsep was being used incorrectly and some of the error paths I
was expecting to be hit weren't and just fell through to the common
invalid key error case.

It also became obvious that for keyword assignments, it wasn't
necessary to save the full assignment and reparse it later, and having
a common empty-assignment check would also make more sense in terms of
error processing.

Change the code to fix these problems and simplify it for new error
message changes in a subsequent patch.

Link: http://lkml.kernel.org/r/1c3ef0b6655deaf345f6faee2584a0298ac2d743.1561743018.git.zanussi@kernel.org

Fixes: e62347d24534 ("tracing: Add hist trigger support for user-defined sorting ('sort=' param)")
Fixes: 7ef224d1d0e3 ("tracing: Add 'hist' event trigger command")
Fixes: a4072fe85ba3 ("tracing: Add a clock attribute for hist triggers")
Reported-by: Masami Hiramatsu <mhiramat@...nel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@...nel.org>
Signed-off-by: Tom Zanussi <zanussi@...nel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@...dmis.org>
---
 kernel/trace/trace_events_hist.c | 70 ++++++++++++--------------------
 1 file changed, 27 insertions(+), 43 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 117a1202a6b9..bf2bcb8d7725 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -2039,12 +2039,6 @@ static int parse_map_size(char *str)
 	unsigned long size, map_bits;
 	int ret;
 
-	strsep(&str, "=");
-	if (!str) {
-		ret = -EINVAL;
-		goto out;
-	}
-
 	ret = kstrtoul(str, 0, &size);
 	if (ret)
 		goto out;
@@ -2104,25 +2098,25 @@ static int parse_action(char *str, struct hist_trigger_attrs *attrs)
 static int parse_assignment(struct trace_array *tr,
 			    char *str, struct hist_trigger_attrs *attrs)
 {
-	int ret = 0;
+	int len, ret = 0;
 
-	if ((str_has_prefix(str, "key=")) ||
-	    (str_has_prefix(str, "keys="))) {
-		attrs->keys_str = kstrdup(str, GFP_KERNEL);
+	if ((len = str_has_prefix(str, "key=")) ||
+	    (len = str_has_prefix(str, "keys="))) {
+		attrs->keys_str = kstrdup(str + len, GFP_KERNEL);
 		if (!attrs->keys_str) {
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if ((str_has_prefix(str, "val=")) ||
-		   (str_has_prefix(str, "vals=")) ||
-		   (str_has_prefix(str, "values="))) {
-		attrs->vals_str = kstrdup(str, GFP_KERNEL);
+	} else if ((len = str_has_prefix(str, "val=")) ||
+		   (len = str_has_prefix(str, "vals=")) ||
+		   (len = str_has_prefix(str, "values="))) {
+		attrs->vals_str = kstrdup(str + len, GFP_KERNEL);
 		if (!attrs->vals_str) {
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if (str_has_prefix(str, "sort=")) {
-		attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
+	} else if ((len = str_has_prefix(str, "sort="))) {
+		attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL);
 		if (!attrs->sort_key_str) {
 			ret = -ENOMEM;
 			goto out;
@@ -2133,12 +2127,8 @@ static int parse_assignment(struct trace_array *tr,
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if (str_has_prefix(str, "clock=")) {
-		strsep(&str, "=");
-		if (!str) {
-			ret = -EINVAL;
-			goto out;
-		}
+	} else if ((len = str_has_prefix(str, "clock="))) {
+		str += len;
 
 		str = strstrip(str);
 		attrs->clock = kstrdup(str, GFP_KERNEL);
@@ -2146,8 +2136,8 @@ static int parse_assignment(struct trace_array *tr,
 			ret = -ENOMEM;
 			goto out;
 		}
-	} else if (str_has_prefix(str, "size=")) {
-		int map_bits = parse_map_size(str);
+	} else if ((len = str_has_prefix(str, "size="))) {
+		int map_bits = parse_map_size(str + len);
 
 		if (map_bits < 0) {
 			ret = map_bits;
@@ -2187,8 +2177,14 @@ parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str)
 
 	while (trigger_str) {
 		char *str = strsep(&trigger_str, ":");
+		char *rhs;
 
-		if (strchr(str, '=')) {
+		rhs = strchr(str, '=');
+		if (rhs) {
+			if (!strlen(++rhs)) {
+				ret = -EINVAL;
+				goto free;
+			}
 			ret = parse_assignment(tr, str, attrs);
 			if (ret)
 				goto free;
@@ -4522,10 +4518,6 @@ static int create_val_fields(struct hist_trigger_data *hist_data,
 	if (!fields_str)
 		goto out;
 
-	strsep(&fields_str, "=");
-	if (!fields_str)
-		goto out;
-
 	for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
 		     j < TRACING_MAP_VALS_MAX; i++) {
 		field_str = strsep(&fields_str, ",");
@@ -4620,10 +4612,6 @@ static int create_key_fields(struct hist_trigger_data *hist_data,
 	if (!fields_str)
 		goto out;
 
-	strsep(&fields_str, "=");
-	if (!fields_str)
-		goto out;
-
 	for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
 		field_str = strsep(&fields_str, ",");
 		if (!field_str)
@@ -4781,12 +4769,6 @@ static int create_sort_keys(struct hist_trigger_data *hist_data)
 	if (!fields_str)
 		goto out;
 
-	strsep(&fields_str, "=");
-	if (!fields_str) {
-		ret = -EINVAL;
-		goto out;
-	}
-
 	for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
 		struct hist_field *hist_field;
 		char *field_str, *field_name;
@@ -4795,9 +4777,11 @@ static int create_sort_keys(struct hist_trigger_data *hist_data)
 		sort_key = &hist_data->sort_keys[i];
 
 		field_str = strsep(&fields_str, ",");
-		if (!field_str) {
-			if (i == 0)
-				ret = -EINVAL;
+		if (!field_str)
+			break;
+
+		if (!*field_str) {
+			ret = -EINVAL;
 			break;
 		}
 
@@ -4807,7 +4791,7 @@ static int create_sort_keys(struct hist_trigger_data *hist_data)
 		}
 
 		field_name = strsep(&field_str, ".");
-		if (!field_name) {
+		if (!field_name || !*field_name) {
 			ret = -EINVAL;
 			break;
 		}
-- 
2.24.1


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ