3 files changed, 47 insertions, 21 deletions

diff --git a/sys/kern/link_elf.c b/sys/kern/link_elf.c
index ebd203858b66..45edd186e6ce 100644
--- a/sys/kern/link_elf.c
+++ b/sys/kern/link_elf.c
@@ -155,7 +155,7 @@ static int	link_elf_search_symbol(linker_file_t, caddr_t,
 		    c_linker_sym_t *, long *);
 
 static void	link_elf_unload_file(linker_file_t);
-static void	link_elf_unload_preload(linker_file_t);
+static void	link_elf_unload_preload(elf_file_t);
 static int	link_elf_lookup_set(linker_file_t, const char *,
 		    void ***, void ***, int *);
 static int	link_elf_each_function_name(linker_file_t,
@@ -799,10 +799,10 @@ parse_vnet(elf_file_t ef)
 
 /*
  * Apply the specified protection to the loadable segments of a preloaded linker
- * file.
+ * file.  If "reset" is not set, the original segment protections are ORed in.
  */
 static int
-preload_protect(elf_file_t ef, vm_prot_t prot)
+preload_protect1(elf_file_t ef, vm_prot_t prot, bool reset)
 {
 #if defined(__aarch64__) || defined(__amd64__)
 	Elf_Ehdr *hdr;
@@ -818,13 +818,16 @@ preload_protect(elf_file_t ef, vm_prot_t prot)
 		if (phdr->p_type != PT_LOAD)
 			continue;
 
-		nprot = prot | VM_PROT_READ;
-		if ((phdr->p_flags & PF_W) != 0)
-			nprot |= VM_PROT_WRITE;
-		if ((phdr->p_flags & PF_X) != 0)
-			nprot |= VM_PROT_EXECUTE;
+		nprot = VM_PROT_NONE;
+		if (!reset) {
+			nprot = VM_PROT_READ;
+			if ((phdr->p_flags & PF_W) != 0)
+				nprot |= VM_PROT_WRITE;
+			if ((phdr->p_flags & PF_X) != 0)
+				nprot |= VM_PROT_EXECUTE;
+		}
 		error = pmap_change_prot((vm_offset_t)ef->address +
-		    phdr->p_vaddr, round_page(phdr->p_memsz), nprot);
+		    phdr->p_vaddr, round_page(phdr->p_memsz), prot | nprot);
 		if (error != 0)
 			break;
 	}
@@ -834,6 +837,18 @@ preload_protect(elf_file_t ef, vm_prot_t prot)
 #endif
 }
 
+static int
+preload_protect(elf_file_t ef, vm_prot_t prot)
+{
+	return (preload_protect1(ef, prot, false));
+}
+
+static int
+preload_protect_reset(elf_file_t ef, vm_prot_t prot)
+{
+	return (preload_protect1(ef, prot, true));
+}
+
 #ifdef __arm__
 /*
  * Locate the ARM exception/unwind table info for DDB and stack(9) use by
@@ -1396,7 +1411,7 @@ link_elf_unload_file(linker_file_t file)
 	elf_cpu_unload_file(file);
 
 	if (ef->preloaded) {
-		link_elf_unload_preload(file);
+		link_elf_unload_preload(ef);
 		return;
 	}
 
@@ -1417,11 +1432,16 @@ link_elf_unload_file(linker_file_t file)
 }
 
 static void
-link_elf_unload_preload(linker_file_t file)
+link_elf_unload_preload(elf_file_t ef)
 {
+	/*
+	 * Reset mapping protections to their original state.  This affects the
+	 * direct map alias of the module mapping as well.
+	 */
+	preload_protect_reset(ef, VM_PROT_RW);
 
-	if (file->pathname != NULL)
-		preload_delete_name(file->pathname);
+	if (ef->lf.pathname != NULL)
+		preload_delete_name(ef->lf.pathname);
 }
 
 static const char *
diff --git a/sys/kern/link_elf_obj.c b/sys/kern/link_elf_obj.c
index a3a53a39bfd6..4128baa5a909 100644
--- a/sys/kern/link_elf_obj.c
+++ b/sys/kern/link_elf_obj.c
@@ -1305,6 +1305,20 @@ link_elf_unload_file(linker_file_t file)
 				vnet_data_free(ef->progtab[i].addr,
 				    ef->progtab[i].size);
 #endif
+			else if (ef->preloaded) {
+				vm_offset_t start, end;
+
+				start = (vm_offset_t)ef->progtab[i].addr;
+				end = start + ef->progtab[i].size;
+
+				/*
+				 * Reset mapping protections to their original
+				 * state.  This affects the direct map alias of
+				 * the module mapping as well.
+				 */
+				link_elf_protect_range(ef, trunc_page(start),
+				    round_page(end), VM_PROT_RW);
+			}
 		}
 	}
 	if (ef->preloaded) {
diff --git a/sys/vm/vm_kern.c b/sys/vm/vm_kern.c
index ac327aa37b72..626632b74add 100644
--- a/sys/vm/vm_kern.c
+++ b/sys/vm/vm_kern.c
@@ -953,14 +953,6 @@ kmem_bootstrap_free(vm_offset_t start, vm_size_t size)
 	end = trunc_page(start + size);
 	start = round_page(start);
 
-#ifdef __amd64__
-	/*
-	 * Preloaded files do not have execute permissions by default on amd64.
-	 * Restore the default permissions to ensure that the direct map alias
-	 * is updated.
-	 */
-	pmap_change_prot(start, end - start, VM_PROT_RW);
-#endif
 	for (va = start; va < end; va += PAGE_SIZE) {
 		pa = pmap_kextract(va);
 		m = PHYS_TO_VM_PAGE(pa);