[PATCH v2 -next] of: unittest: fix null pointer dereferencing in of_unittest_find_node_by_name()

Ruan Jinjie posted 1 patch 2 years, 6 months ago
drivers/of/unittest.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
[PATCH v2 -next] of: unittest: fix null pointer dereferencing in of_unittest_find_node_by_name()
Posted by Ruan Jinjie 2 years, 6 months ago
when kmalloc() fail to allocate memory in kasprintf(), name
or full_name will be NULL, strcmp() will cause
null pointer dereference.

Fixes: 0d638a07d3a1 ("of: Convert to using %pOF instead of full_name")
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
---
v2:
- add fixes tag
---
 drivers/of/unittest.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index a406a12eb208..e5b0eea8011c 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -77,7 +77,7 @@ static void __init of_unittest_find_node_by_name(void)
 
 	np = of_find_node_by_path("/testcase-data");
 	name = kasprintf(GFP_KERNEL, "%pOF", np);
-	unittest(np && !strcmp("/testcase-data", name),
+	unittest(np && name && !strcmp("/testcase-data", name),
 		"find /testcase-data failed\n");
 	of_node_put(np);
 	kfree(name);
@@ -88,14 +88,14 @@ static void __init of_unittest_find_node_by_name(void)
 
 	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
 	name = kasprintf(GFP_KERNEL, "%pOF", np);
-	unittest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", name),
+	unittest(np && name && !strcmp("/testcase-data/phandle-tests/consumer-a", name),
 		"find /testcase-data/phandle-tests/consumer-a failed\n");
 	of_node_put(np);
 	kfree(name);
 
 	np = of_find_node_by_path("testcase-alias");
 	name = kasprintf(GFP_KERNEL, "%pOF", np);
-	unittest(np && !strcmp("/testcase-data", name),
+	unittest(np && name && !strcmp("/testcase-data", name),
 		"find testcase-alias failed\n");
 	of_node_put(np);
 	kfree(name);
@@ -106,7 +106,7 @@ static void __init of_unittest_find_node_by_name(void)
 
 	np = of_find_node_by_path("testcase-alias/phandle-tests/consumer-a");
 	name = kasprintf(GFP_KERNEL, "%pOF", np);
-	unittest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", name),
+	unittest(np && name && !strcmp("/testcase-data/phandle-tests/consumer-a", name),
 		"find testcase-alias/phandle-tests/consumer-a failed\n");
 	of_node_put(np);
 	kfree(name);
@@ -1533,6 +1533,8 @@ static void attach_node_and_children(struct device_node *np)
 	const char *full_name;
 
 	full_name = kasprintf(GFP_KERNEL, "%pOF", np);
+	if (!full_name)
+		return;
 
 	if (!strcmp(full_name, "/__local_fixups__") ||
 	    !strcmp(full_name, "/__fixups__")) {
-- 
2.34.1
Re: [PATCH v2 -next] of: unittest: fix null pointer dereferencing in of_unittest_find_node_by_name()
Posted by Rob Herring 2 years, 6 months ago
On Thu, 27 Jul 2023 16:02:46 +0800, Ruan Jinjie wrote:
> when kmalloc() fail to allocate memory in kasprintf(), name
> or full_name will be NULL, strcmp() will cause
> null pointer dereference.
> 
> Fixes: 0d638a07d3a1 ("of: Convert to using %pOF instead of full_name")
> Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
> ---
> v2:
> - add fixes tag
> ---
>  drivers/of/unittest.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 

Applied, thanks!