In descs_to_legacy(), the return value of malloc() is used without a
NULL check. If malloc() fails, dereferencing the resulting pointer
leads to a NULL pointer dereference. Add a NULL check and return 0 on
failure, consistent with the existing error handling at the start of
the function.

Signed-off-by: longlong yan <yanlonglong@kylinos.cn>
---
 tools/usb/ffs-test.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/usb/ffs-test.c b/tools/usb/ffs-test.c
index 22b938fbdfb7..5c9281cbbff1 100644
--- a/tools/usb/ffs-test.c
+++ b/tools/usb/ffs-test.c
@@ -293,6 +293,8 @@ static size_t descs_to_legacy(void **legacy, const void *descriptors_v2)
 
 		length = sizeof out->header + (descs_end - descs_start);
 		out = malloc(length);
+		if (!out)
+			return 0;
 		out->header.magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC);
 		out->header.length = cpu_to_le32(length);
 		out->header.fs_count = cpu_to_le32(fs_count);
-- 
2.43.0