From: Jan Klemkow <jan@openbsd.org>
Subject: Re: add missing M_PKTHDR check
To: tech@openbsd.org
Date: Thu, 14 Aug 2025 21:36:15 +0200

On Tue, Aug 12, 2025 at 08:59:25PM +0200, Jan Klemkow wrote:
> In all other archs _bus_dmamap_load_mbuf() checks the M_PKTHDR flag
> before using the m_pkthdr struct.

The reset of _dm_type and _dm_source should not depend on DIAGNOSTIC.

ok?

bye,
Jan

Index: arch/sparc64/sparc64/machdep.c
===================================================================
RCS file: /cvs/src/sys/arch/sparc64/sparc64/machdep.c,v
diff -u -p -r1.218 machdep.c
--- arch/sparc64/sparc64/machdep.c	22 May 2024 05:51:49 -0000	1.218
+++ arch/sparc64/sparc64/machdep.c	14 Aug 2025 19:29:55 -0000
@@ -957,6 +957,11 @@ _bus_dmamap_load_mbuf(bus_dma_tag_t t, b
  	map->dm_mapsize = 0;
  	map->dm_nsegs = 0;
 
+#ifdef DIAGNOSTIC
+	if ((m->m_flags & M_PKTHDR) == 0)
+		panic("_bus_dmamap_load_mbuf: no packet header");
+#endif
+
 	if (m->m_pkthdr.len > map->_dm_size)
 		return (EINVAL);
 
@@ -982,9 +987,10 @@ _bus_dmamap_load_mbuf(bus_dma_tag_t t, b
 #ifdef DIAGNOSTIC
 				printf("_bus_dmamap_load_mbuf: pmap_extract failed %lx\n",
 					vaddr);
+#endif
 				map->_dm_type = 0;
 				map->_dm_source = NULL;
-#endif
+
 				return EINVAL;
 			}
 
@@ -1014,8 +1020,7 @@ _bus_dmamap_load_mbuf(bus_dma_tag_t t, b
 		}
 	}
 
-	return (bus_dmamap_load_raw(t0, map, segs, i,
-			    (bus_size_t)len, flags));
+	return (bus_dmamap_load_raw(t0, map, segs, i, (bus_size_t)len, flags));
 }
 
 /*