The trace functions use a buffer to manipulate strings that will be
written to tracefs files. These buffers are defined with a magic number
of 1024, which is a common source of vulnerabilities.

Replace the magic number 1024 with the MAX_PATH macro to make the code
safer and more readable. While at it, replace other instances of the
magic number with ARRAY_SIZE() when the buffer is locally defined.

Signed-off-by: Wander Lairson Costa <[email protected]>
---
 tools/tracing/rtla/src/osnoise.c    |  4 ++--
 tools/tracing/rtla/src/timerlat_u.c |  4 ++--
 tools/tracing/rtla/src/trace.c      | 20 ++++++++++----------
 3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/tools/tracing/rtla/src/osnoise.c b/tools/tracing/rtla/src/osnoise.c
index 5075e0f485c77..d502cbbcea91b 100644
--- a/tools/tracing/rtla/src/osnoise.c
+++ b/tools/tracing/rtla/src/osnoise.c
@@ -52,7 +52,7 @@ char *osnoise_get_cpus(struct osnoise_context *context)
 int osnoise_set_cpus(struct osnoise_context *context, char *cpus)
 {
        char *orig_cpus = osnoise_get_cpus(context);
-       char buffer[1024];
+       char buffer[MAX_PATH];
        int retval;
 
        if (!orig_cpus)
@@ -62,7 +62,7 @@ int osnoise_set_cpus(struct osnoise_context *context, char 
*cpus)
        if (!context->curr_cpus)
                return -1;
 
-       snprintf(buffer, 1024, "%s\n", cpus);
+       snprintf(buffer, ARRAY_SIZE(buffer), "%s\n", cpus);
 
        debug_msg("setting cpus to %s from %s", cpus, context->orig_cpus);
 
diff --git a/tools/tracing/rtla/src/timerlat_u.c 
b/tools/tracing/rtla/src/timerlat_u.c
index 01dbf9a6b5a51..52977e725c79c 100644
--- a/tools/tracing/rtla/src/timerlat_u.c
+++ b/tools/tracing/rtla/src/timerlat_u.c
@@ -32,7 +32,7 @@
 static int timerlat_u_main(int cpu, struct timerlat_u_params *params)
 {
        struct sched_param sp = { .sched_priority = 95 };
-       char buffer[1024];
+       char buffer[MAX_PATH];
        int timerlat_fd;
        cpu_set_t set;
        int retval;
@@ -87,7 +87,7 @@ static int timerlat_u_main(int cpu, struct timerlat_u_params 
*params)
 
        /* add should continue with a signal handler */
        while (true) {
-               retval = read(timerlat_fd, buffer, 1024);
+               retval = read(timerlat_fd, buffer, ARRAY_SIZE(buffer));
                if (retval < 0)
                        break;
        }
diff --git a/tools/tracing/rtla/src/trace.c b/tools/tracing/rtla/src/trace.c
index 813f4368f104b..658a6e94edfba 100644
--- a/tools/tracing/rtla/src/trace.c
+++ b/tools/tracing/rtla/src/trace.c
@@ -330,7 +330,7 @@ int trace_event_add_trigger(struct trace_events *event, 
char *trigger)
 static void trace_event_disable_filter(struct trace_instance *instance,
                                       struct trace_events *tevent)
 {
-       char filter[1024];
+       char filter[MAX_PATH];
        int retval;
 
        if (!tevent->filter)
@@ -342,7 +342,7 @@ static void trace_event_disable_filter(struct 
trace_instance *instance,
        debug_msg("Disabling %s:%s filter %s\n", tevent->system,
                  tevent->event ? : "*", tevent->filter);
 
-       snprintf(filter, 1024, "!%s\n", tevent->filter);
+       snprintf(filter, ARRAY_SIZE(filter), "!%s\n", tevent->filter);
 
        retval = tracefs_event_file_write(instance->inst, tevent->system,
                                          tevent->event, "filter", filter);
@@ -361,7 +361,7 @@ static void trace_event_save_hist(struct trace_instance 
*instance,
 {
        int retval, index, out_fd;
        mode_t mode = 0644;
-       char path[1024];
+       char path[MAX_PATH];
        char *hist;
 
        if (!tevent)
@@ -376,7 +376,7 @@ static void trace_event_save_hist(struct trace_instance 
*instance,
        if (retval)
                return;
 
-       snprintf(path, 1024, "%s_%s_hist.txt", tevent->system, tevent->event);
+       snprintf(path, ARRAY_SIZE(path), "%s_%s_hist.txt", tevent->system, 
tevent->event);
 
        printf("  Saving event %s:%s hist to %s\n", tevent->system, 
tevent->event, path);
 
@@ -408,7 +408,7 @@ static void trace_event_save_hist(struct trace_instance 
*instance,
 static void trace_event_disable_trigger(struct trace_instance *instance,
                                        struct trace_events *tevent)
 {
-       char trigger[1024];
+       char trigger[MAX_PATH];
        int retval;
 
        if (!tevent->trigger)
@@ -422,7 +422,7 @@ static void trace_event_disable_trigger(struct 
trace_instance *instance,
 
        trace_event_save_hist(instance, tevent);
 
-       snprintf(trigger, 1024, "!%s\n", tevent->trigger);
+       snprintf(trigger, ARRAY_SIZE(trigger), "!%s\n", tevent->trigger);
 
        retval = tracefs_event_file_write(instance->inst, tevent->system,
                                          tevent->event, "trigger", trigger);
@@ -461,7 +461,7 @@ void trace_events_disable(struct trace_instance *instance,
 static int trace_event_enable_filter(struct trace_instance *instance,
                                     struct trace_events *tevent)
 {
-       char filter[1024];
+       char filter[MAX_PATH];
        int retval;
 
        if (!tevent->filter)
@@ -473,7 +473,7 @@ static int trace_event_enable_filter(struct trace_instance 
*instance,
                return 1;
        }
 
-       snprintf(filter, 1024, "%s\n", tevent->filter);
+       snprintf(filter, ARRAY_SIZE(filter), "%s\n", tevent->filter);
 
        debug_msg("Enabling %s:%s filter %s\n", tevent->system,
                  tevent->event ? : "*", tevent->filter);
@@ -496,7 +496,7 @@ static int trace_event_enable_filter(struct trace_instance 
*instance,
 static int trace_event_enable_trigger(struct trace_instance *instance,
                                      struct trace_events *tevent)
 {
-       char trigger[1024];
+       char trigger[MAX_PATH];
        int retval;
 
        if (!tevent->trigger)
@@ -508,7 +508,7 @@ static int trace_event_enable_trigger(struct trace_instance 
*instance,
                return 1;
        }
 
-       snprintf(trigger, 1024, "%s\n", tevent->trigger);
+       snprintf(trigger, ARRAY_SIZE(trigger), "%s\n", tevent->trigger);
 
        debug_msg("Enabling %s:%s trigger %s\n", tevent->system,
                  tevent->event ? : "*", tevent->trigger);
-- 
2.51.1


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