When copying a type from a source CTF container to a destination container,

ctf_add_type() first performs a by-name lookup of the type in the
destination container. If this lookup returns a forward declaration for an
enum, struct, or union, reset dst_type back to CTF_ERR, indicating that the
source type is not in fact present in the destination container. This
ensures that ctf_add_type() will also search the destination container's
dynamic type list for the source type.

Without this change, a pair of mutually recursive struct definitions could
cause infinite recursion in ctf_add_type() if the destination container
only contained forward declarations for the struct types: ctf_add_type()
recursively calls itself on each struct member's type, and the forward
declarations meant that the dynamic type list search would be skipped.

MFC after:	2 weeks
Sponsored by:	EMC / Isilon Storage Division

1 files changed, 7 insertions, 4 deletions

diff --git a/cddl/contrib/opensolaris/common/ctf/ctf_create.c b/cddl/contrib/opensolaris/common/ctf/ctf_create.c
index 679ed18..1c0988a 100644
--- a/cddl/contrib/opensolaris/common/ctf/ctf_create.c
+++ b/cddl/contrib/opensolaris/common/ctf/ctf_create.c
@@ -1313,10 +1313,13 @@ ctf_add_type(ctf_file_t *dst_fp, ctf_file_t *src_fp, ctf_id_t src_type)
 	 * unless dst_type is a forward declaration and src_type is a struct,
 	 * union, or enum (i.e. the definition of the previous forward decl).
 	 */
-	if (dst_type != CTF_ERR && dst_kind != kind && (
-	    dst_kind != CTF_K_FORWARD || (kind != CTF_K_ENUM &&
-	    kind != CTF_K_STRUCT && kind != CTF_K_UNION)))
-		return (ctf_set_errno(dst_fp, ECTF_CONFLICT));
+	if (dst_type != CTF_ERR && dst_kind != kind) {
+		if (dst_kind != CTF_K_FORWARD || (kind != CTF_K_ENUM &&
+		    kind != CTF_K_STRUCT && kind != CTF_K_UNION))
+			return (ctf_set_errno(dst_fp, ECTF_CONFLICT));
+		else
+			dst_type = CTF_ERR;
+	}
 
 	/*
 	 * If the non-empty name was not found in the appropriate hash, search