It can return EINVAL instead.
This improves the stability of the system and DX of an inexperienced
programmer at a minor cost of a simple if statement.
Example call to:
error_t err = diskfs_lookup (node, ".", LOOKUP, &child, NULL, NULL);
Before this fix:
System crash, needs a restart...
After this fix:
err = EINVAL
---
libdiskfs/lookup.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/libdiskfs/lookup.c b/libdiskfs/lookup.c
index 201613c3..0f23cbe8 100644
--- a/libdiskfs/lookup.c
+++ b/libdiskfs/lookup.c
@@ -63,6 +63,7 @@
Return ENOTDIR if DP is not a directory.
Return EACCES if CRED isn't allowed to search DP.
+ Return EINVAL if CRED is 0.
Return EACCES if completing the operation will require writing
the directory and diskfs_checkdirmod won't allow the modification.
Return ENOENT if NAME isn't in the directory.
@@ -77,6 +78,9 @@ diskfs_lookup (struct node *dp, char *name, enum lookup_type
type,
error_t err;
struct node *cached;
+ if (!cred)
+ return EINVAL;
+
if (type == REMOVE || type == RENAME)
assert_backtrace (np);
--
2.52.0
