[PATCH net-next 1/2] tools: ynl: check for null ptr on dump free

Static analysis detected code paths where freeing a dump list after early
errors when creating the corresponding dump list like in ynl_exec_dump()
can result in a null pointer dereference since the first node in the
ynl_dump_state would still be zero initialized. To prevent this potential
problem updated the ynl c generation script to check for a NULL pointer
before continuing to free the nodes in a dump list.

Signed-off-by: Thaison Phan <[email protected]>
---
 tools/net/ynl/pyynl/ynl_gen_c.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen_c.py
index cdc3646f2642..2fd68c738075 100755
--- a/tools/net/ynl/pyynl/ynl_gen_c.py
+++ b/tools/net/ynl/pyynl/ynl_gen_c.py
@@ -2747,7 +2747,7 @@ def print_dump_type_free(ri):
     ri.cw.block_start()
     ri.cw.p(f"{sub_type} *next = rsp;")
     ri.cw.nl()
-    ri.cw.block_start(line='while ((void *)next != YNL_LIST_END)')
+    ri.cw.block_start(line='while (next && (void *)next != YNL_LIST_END)')
     _free_type_members_iter(ri, ri.struct['reply'])
     ri.cw.p('rsp = next;')
     ri.cw.p('next = rsp->next;')
-- 
2.55.0.571.g244d577d93-goog