Hi Linus,
Please pull the following KUnit fixes update for Linux 6.11-rc7.
This kunit update for Linux 6.11-rc7 consist of one single fix to
a use-after-free bug resulting from kunit_driver_create() failing
to copy the driver name leaving it on the stack or freeing it.
diff is attached.
thanks,
-- Shuah
----------------------------------------------------------------
The following changes since commit 8400291e289ee6b2bf9779ff1c83a291501f017b:
Linux 6.11-rc1 (2024-07-28 14:19:55 -0700)
are available in the Git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest tags/linux_kselftest-kunit-fixes-6.11-rc7
for you to fetch changes up to f2c6dbd220170c2396fb019ead67fbada1e23ebd:
kunit: Device wrappers should also manage driver name (2024-08-26 07:03:46 -0600)
----------------------------------------------------------------
linux_kselftest-kunit-fixes-6.11-rc7
This kunit update for Linux 6.11-rc7 consist of one single fix to
a use-after-free bug resulting from kunit_driver_create() failing
to copy the driver name leaving it on the stack or freeing it.
----------------------------------------------------------------
David Gow (1):
kunit: Device wrappers should also manage driver name
include/kunit/test.h | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
lib/kunit/device.c | 7 +++++--
lib/kunit/test.c | 19 +++++++++++++++++++
3 files changed, 72 insertions(+), 2 deletions(-)
----------------------------------------------------------------diff --git a/include/kunit/test.h b/include/kunit/test.h
index e2a1f0928e8b..5ac237c949a0 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -28,6 +28,7 @@
#include <linux/types.h>
#include <asm/rwonce.h>
+#include <asm/sections.h>
/* Static key: true if any KUnit tests are currently running */
DECLARE_STATIC_KEY_FALSE(kunit_running);
@@ -480,6 +481,53 @@ static inline void *kunit_kcalloc(struct kunit *test, size_t n, size_t size, gfp
return kunit_kmalloc_array(test, n, size, gfp | __GFP_ZERO);
}
+
+/**
+ * kunit_kfree_const() - conditionally free test managed memory
+ * @x: pointer to the memory
+ *
+ * Calls kunit_kfree() only if @x is not in .rodata section.
+ * See kunit_kstrdup_const() for more information.
+ */
+void kunit_kfree_const(struct kunit *test, const void *x);
+
+/**
+ * kunit_kstrdup() - Duplicates a string into a test managed allocation.
+ *
+ * @test: The test context object.
+ * @str: The NULL-terminated string to duplicate.
+ * @gfp: flags passed to underlying kmalloc().
+ *
+ * See kstrdup() and kunit_kmalloc_array() for more information.
+ */
+static inline char *kunit_kstrdup(struct kunit *test, const char *str, gfp_t gfp)
+{
+ size_t len;
+ char *buf;
+
+ if (!str)
+ return NULL;
+
+ len = strlen(str) + 1;
+ buf = kunit_kmalloc(test, len, gfp);
+ if (buf)
+ memcpy(buf, str, len);
+ return buf;
+}
+
+/**
+ * kunit_kstrdup_const() - Conditionally duplicates a string into a test managed allocation.
+ *
+ * @test: The test context object.
+ * @str: The NULL-terminated string to duplicate.
+ * @gfp: flags passed to underlying kmalloc().
+ *
+ * Calls kunit_kstrdup() only if @str is not in the rodata section. Must be freed with
+ * kunit_kfree_const() -- not kunit_kfree().
+ * See kstrdup_const() and kunit_kmalloc_array() for more information.
+ */
+const char *kunit_kstrdup_const(struct kunit *test, const char *str, gfp_t gfp);
+
/**
* kunit_vm_mmap() - Allocate KUnit-tracked vm_mmap() area
* @test: The test context object.
diff --git a/lib/kunit/device.c b/lib/kunit/device.c
index 25c81ed465fb..520c1fccee8a 100644
--- a/lib/kunit/device.c
+++ b/lib/kunit/device.c
@@ -89,7 +89,7 @@ struct device_driver *kunit_driver_create(struct kunit *test, const char *name)
if (!driver)
return ERR_PTR(err);
- driver->name = name;
+ driver->name = kunit_kstrdup_const(test, name, GFP_KERNEL);
driver->bus = &kunit_bus_type;
driver->owner = THIS_MODULE;
@@ -192,8 +192,11 @@ void kunit_device_unregister(struct kunit *test, struct device *dev)
const struct device_driver *driver = to_kunit_device(dev)->driver;
kunit_release_action(test, device_unregister_wrapper, dev);
- if (driver)
+ if (driver) {
+ const char *driver_name = driver->name;
kunit_release_action(test, driver_unregister_wrapper, (void *)driver);
+ kunit_kfree_const(test, driver_name);
+ }
}
EXPORT_SYMBOL_GPL(kunit_device_unregister);
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index e8b1b52a19ab..089c832e3cdb 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -874,6 +874,25 @@ void kunit_kfree(struct kunit *test, const void *ptr)
}
EXPORT_SYMBOL_GPL(kunit_kfree);
+void kunit_kfree_const(struct kunit *test, const void *x)
+{
+#if !IS_MODULE(CONFIG_KUNIT)
+ if (!is_kernel_rodata((unsigned long)x))
+#endif
+ kunit_kfree(test, x);
+}
+EXPORT_SYMBOL_GPL(kunit_kfree_const);
+
+const char *kunit_kstrdup_const(struct kunit *test, const char *str, gfp_t gfp)
+{
+#if !IS_MODULE(CONFIG_KUNIT)
+ if (is_kernel_rodata((unsigned long)str))
+ return str;
+#endif
+ return kunit_kstrdup(test, str, gfp);
+}
+EXPORT_SYMBOL_GPL(kunit_kstrdup_const);
+
void kunit_cleanup(struct kunit *test)
{
struct kunit_resource *res;
