[GIT PULL] tracing: Three more updates for 4.12

[GIT PULL] tracing: Three more updates for 4.12

[Steven Rostedt]

Linus,

These are three simple changes.

The first one is just a switch from using strcpy() to strlcpy(). Someone
thought that it may cause an overflow bug, but since it only copies comms
into a pre-allocated array of TASK_COMM_LEN, and no comm should ever
be bigger than that, nor not end with a nul character, this change is more
of a safety precaution than fixing anything that is actually broken.

The other two changes are simply cleaning and optimizing some code.

Note, I added these on top of the commit that you merged. That way, I
was able to test these patches along with your merge changes.

Please pull the latest trace-v4.12-2 tree, which can be found at:


  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
trace-v4.12-2

Tag SHA1: 3c4613102e8eb14cdc740cc662dea4be03205cd8
Head SHA1: 77c0eddeeeee14bf0fb0c0bb97e782981bbcf084


Amey Telawane (1):
      tracing: Use strlcpy() instead of strcpy() in __trace_find_cmdline()

Dan Carpenter (1):
      ftrace: Remove an unneeded condition

Steven Rostedt (VMware) (1):
      ftrace: Simplify ftrace_match_record() even more

----
 kernel/trace/ftrace.c | 20 +++++++++-----------
 kernel/trace/trace.c  |  2 +-
 2 files changed, 10 insertions(+), 12 deletions(-)
---------------------------
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 00077a57b746..39dca4e86a94 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3631,22 +3631,20 @@ ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g,
 		/* blank module name to match all modules */
 		if (!mod_g->len) {
 			/* blank module globbing: modname xor exclude_mod */
-			if ((!exclude_mod) != (!modname))
+			if (!exclude_mod != !modname)
 				goto func_match;
 			return 0;
 		}
 
-		/* not matching the module */
-		if (!modname || !mod_matches) {
-			if (exclude_mod)
-				goto func_match;
-			else
-				return 0;
-		}
-
-		if (mod_matches && exclude_mod)
+		/*
+		 * exclude_mod is set to trace everything but the given
+		 * module. If it is set and the module matches, then
+		 * return 0. If it is not set, and the module doesn't match
+		 * also return 0. Otherwise, check the function to see if
+		 * that matches.
+		 */
+		if (!mod_matches == !exclude_mod)
 			return 0;
-
 func_match:
 		/* blank search means to match all funcs in the mod */
 		if (!func_g->len)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 80eda7d254ed..4ad4420b33d6 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1976,7 +1976,7 @@ static void __trace_find_cmdline(int pid, char comm[])
 
 	map = savedcmd->map_pid_to_cmdline[pid];
 	if (map != NO_CMDLINE_MAP)
-		strcpy(comm, get_saved_cmdlines(map));
+		strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN);
 	else
 		strcpy(comm, "<...>");
 }