FreeBSD: Fix memory leaks in kstats

Ryan Moeller · Ryan Moeller · commit 415e1b428d1e · 2021-03-17T12:02:19.000-04:00
Free the kstat object from the correct malloc zone if allocating data
for a non-virtual kstat fails.

Free the data allocated for non-virtual kstats when deleting the object.

Signed-off-by: Ryan Moeller &lt;ryan@iXsystems.com&gt;
diff --git a/module/os/freebsd/spl/spl_kstat.c b/module/os/freebsd/spl/spl_kstat.c
@@ -304,7 +304,7 @@ __kstat_create(const char *module, int instance, const char *name,
 	} else {
 		ksp->ks_data = kmem_zalloc(ksp->ks_data_size, KM_SLEEP);
 		if (ksp->ks_data == NULL) {
-			kmem_free(ksp, sizeof (*ksp));
+			free(ksp, M_KSTAT);
 			ksp = NULL;
 		}
 	}
@@ -509,6 +509,8 @@ kstat_delete(kstat_t *ksp)
 	sysctl_ctx_free(&ksp->ks_sysctl_ctx);
 	ksp->ks_lock = NULL;
 	mutex_destroy(&ksp->ks_private_lock);
+	if (!(ksp->ks_flags & KSTAT_FLAG_VIRTUAL))
+		kmem_free(ksp->ks_data, ksp->ks_data_size);
 	free(ksp, M_KSTAT);
 }
 

Original file line number	Diff line number	Diff line change
`@@ -304,7 +304,7 @@ __kstat_create(const char module, int instance, const char name,`
`304`	`304`	`} else {`
`305`	`305`	`ksp->ks_data = kmem_zalloc(ksp->ks_data_size, KM_SLEEP);`
`306`	`306`	`if (ksp->ks_data == NULL) {`
`307`		`- kmem_free(ksp, sizeof (*ksp));`
	`307`	`+ free(ksp, M_KSTAT);`
`308`	`308`	`ksp = NULL;`
`309`	`309`	`}`
`310`	`310`	`}`
`@@ -509,6 +509,8 @@ kstat_delete(kstat_t *ksp)`
`509`	`509`	`sysctl_ctx_free(&ksp->ks_sysctl_ctx);`
`510`	`510`	`ksp->ks_lock = NULL;`
`511`	`511`	`mutex_destroy(&ksp->ks_private_lock);`
	`512`	`+ if (!(ksp->ks_flags & KSTAT_FLAG_VIRTUAL))`
	`513`	`+ kmem_free(ksp->ks_data, ksp->ks_data_size);`
`512`	`514`	`free(ksp, M_KSTAT);`
`513`	`515`	`}`
`514`	`516`