From: Michael Jeanson <mjeanson@efficios.com>
Date: Fri, 16 Oct 2020 19:44:36 +0000 (-0400)
Subject: fix: pthread_setname_np fails on longer tread names
X-Git-Tag: v2.13.0-rc1~474
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=f2db7517e508d970c8a5bebfb05334dc5ee72b87;p=lttng-ust.git

fix: pthread_setname_np fails on longer tread names

When supplied with a thread name of more than 16 bytes including the
null terminating byte pthread_setname_np will fail with ERANGE,
replicate this behavior in the compat wrappers.

Change-Id: I91ac35a400a39c297e49fcab83b4f345b7ad92d0
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/liblttng-ust/compat.h b/liblttng-ust/compat.h
index 69761880..a941b9a1 100644
--- a/liblttng-ust/compat.h
+++ b/liblttng-ust/compat.h
@@ -23,6 +23,7 @@
 
 #include <pthread.h>
 #include <errno.h>
+#include <string.h>
 
 #include <lttng/ust-abi.h>
 
@@ -59,6 +60,11 @@ int lttng_pthread_getname_np(char *name, size_t len)
 static inline
 int lttng_pthread_setname_np(const char *name)
 {
+	/* Replicate pthread_setname_np's behavior */
+	if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
+		return ERANGE;
+	}
+
 	pthread_set_name_np(pthread_self(), name);
 	return 0;
 }
@@ -77,6 +83,10 @@ int lttng_pthread_getname_np(char *name, size_t len)
 static inline
 int lttng_pthread_setname_np(const char *name)
 {
+	/* Replicate pthread_setname_np's behavior */
+	if (strnlen(name, LTTNG_UST_ABI_PROCNAME_LEN) >= LTTNG_UST_ABI_PROCNAME_LEN) {
+		return ERANGE;
+	}
 	return prctl(PR_SET_NAME, name, 0, 0, 0);
 }