[igt-dev] [PATCH i-g-t v4 4/9] lib/igt_kmod: don't leak who from module unload routines

[Mauro Carvalho Chehab]

From: Mauro Carvalho Chehab <mchehab at kernel.org>

Add code to free allocated strings at the module unload routines
from igt_kmod.

Signed-off-by: Mauro Carvalho Chehab <mchehab at kernel.org>
---
 lib/igt_kmod.c        | 36 +++++++++++++++++++++++++-----------
 lib/igt_kmod.h        |  4 ++--
 tests/i915/perf_pmu.c |  4 +++-
 3 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/lib/igt_kmod.c b/lib/igt_kmod.c
index ca74c602ce66..3e9302686844 100644
--- a/lib/igt_kmod.c
+++ b/lib/igt_kmod.c
@@ -390,7 +390,7 @@ igt_i915_driver_load(const char *opts)
 	return 0;
 }
 
-static int igt_always_unload_audio_driver(const char **who)
+static int igt_always_unload_audio_driver(char **who)
 {
 	int ret;
 	const char *sound[] = {
@@ -401,8 +401,11 @@ static int igt_always_unload_audio_driver(const char **who)
 
 	for (const char **m = sound; *m; m++) {
 		if (igt_kmod_is_loaded(*m)) {
-			if (who)
-				*who = *m;
+			if (who) {
+				if (*who)
+					free(*who);
+				*who = strdup(*m);
+			}
 			if (igt_lsof_kill_audio_processes())
 				return EACCES;
 
@@ -544,7 +547,7 @@ static int linux_kernel_version(void)
 	return LINUX_VERSION(ver[0], ver[1], ver[2]);
 }
 
-int igt_audio_driver_unload(const char **who)
+int igt_audio_driver_unload(char **who)
 {
 	const char *drm_driver = "i915";
 	unsigned int num_mod, i, j;
@@ -583,8 +586,11 @@ int igt_audio_driver_unload(const char **who)
 	/* Recursively remove all drivers that depend on drm_driver */
 	for (j = 0; j < mod[i].num_required; j++) {
 		pos = mod[i].required_by[j];
-		if (who)
+		if (who) {
+			if (*who)
+				free(who);
 			*who = strdup(mod[pos].name);
+		}
 		/*
 		 * If a sound driver depends on drm_driver, kill audio processes
 		 * first, in order to make it possible to unload the driver
@@ -604,7 +610,7 @@ ret:
 	return ret;
 }
 
-int __igt_i915_driver_unload(const char **who)
+int __igt_i915_driver_unload(char **who)
 {
 	int ret;
 
@@ -631,8 +637,12 @@ int __igt_i915_driver_unload(const char **who)
 
 		ret = igt_kmod_unload(*m, 0);
 		if (ret) {
-			if (who)
-				*who = *m;
+			if (who) {
+				if (*who)
+					free(*who);
+
+				*who = strdup(*m);
+			}
 			return ret;
 		}
 	}
@@ -640,8 +650,11 @@ int __igt_i915_driver_unload(const char **who)
 	if (igt_kmod_is_loaded("i915")) {
 		ret = igt_kmod_unload("i915", 0);
 		if (ret) {
-			if (who)
-				*who = "i915";
+			if (who) {
+				if (*who)
+					free(*who);
+				*who = strdup("i915");
+			}
 			return ret;
 		}
 	}
@@ -658,7 +671,7 @@ int __igt_i915_driver_unload(const char **who)
 int
 igt_i915_driver_unload(void)
 {
-	const char *who;
+	char *who = NULL;
 	int ret;
 
 	ret = __igt_i915_driver_unload(&who);
@@ -667,6 +680,7 @@ igt_i915_driver_unload(void)
 		igt_kmod_list_loaded();
 		igt_lsof("/dev/dri");
 		igt_lsof("/dev/snd");
+		free(who);
 		return ret;
 	}
 
diff --git a/lib/igt_kmod.h b/lib/igt_kmod.h
index 15f0be31e8e4..f98dd29fb175 100644
--- a/lib/igt_kmod.h
+++ b/lib/igt_kmod.h
@@ -36,11 +36,11 @@ bool igt_kmod_has_param(const char *mod_name, const char *param);
 int igt_kmod_load(const char *mod_name, const char *opts);
 int igt_kmod_unload(const char *mod_name, unsigned int flags);
 
-int igt_audio_driver_unload(const char **whom);
+int igt_audio_driver_unload(char **whom);
 
 int igt_i915_driver_load(const char *opts);
 int igt_i915_driver_unload(void);
-int __igt_i915_driver_unload(const char **whom);
+int __igt_i915_driver_unload(char **whom);
 
 int igt_amdgpu_driver_load(const char *opts);
 int igt_amdgpu_driver_unload(void);
diff --git a/tests/i915/perf_pmu.c b/tests/i915/perf_pmu.c
index c48cc07df0d2..ce047eab8296 100644
--- a/tests/i915/perf_pmu.c
+++ b/tests/i915/perf_pmu.c
@@ -2047,7 +2047,7 @@ static void test_unload(unsigned int num_engines)
 		int fd[4 + num_engines * 3], i;
 		uint64_t *buf;
 		int count = 0, ret;
-		const char *who;
+		char *who = NULL;
 		int i915;
 
 		i915 = __drm_open_driver(DRIVER_INTEL);
@@ -2104,6 +2104,8 @@ static void test_unload(unsigned int num_engines)
 		pmu_read_multi(fd[0], count, buf);
 		ret = __igt_i915_driver_unload(&who);
 		igt_assert(ret != 0 && !strcmp(who, "i915"));
+		if (who)
+			free(who);
 		pmu_read_multi(fd[0], count, buf);
 
 		igt_debug("Close perf\n");
-- 
2.36.1