Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull module updates from Luis Chamberlain:
 "The biggest change here is in-kernel support for module decompression.
  This change is being made to help support LSMs like LoadPin as
  otherwise it loses link between the source of kernel module on the
  disk and binary blob that is being loaded into the kernel.

  kmod decompression is still done by userspace even with this is done,
  both because there are no measurable gains in not doing so and as it
  adds a secondary extra check for validating the module before loading
  it into the kernel.

  The rest of the changes are minor, the only other change worth
  mentionin there is Jessica Yu is now bowing out of maintenance of
  modules as she's taking a break from work.

  While there were other changes posted for modules, those have not yet
  received much review of testing so I'm not yet comfortable in merging
  any of those changes yet."

* 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  module: fix signature check failures when using in-kernel decompression
  kernel: Fix spelling mistake "compresser" -> "compressor"
  MAINTAINERS: add mailing lists for kmod and modules
  module.h: allow #define strings to work with MODULE_IMPORT_NS
  module: add in-kernel support for decompressing
  MAINTAINERS: Remove myself as modules maintainer
  module: Remove outdated comment

1 files changed, 29 insertions, 16 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 1038c013d8b2..24dab046e16c 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -958,7 +958,6 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 		}
 	}
 
-	/* Stop the machine so refcounts can't move and disable module. */
 	ret = try_stop_module(mod, flags, &forced);
 	if (ret != 0)
 		goto out;
@@ -2884,12 +2883,13 @@ static int module_sig_check(struct load_info *info, int flags)
 	const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
 	const char *reason;
 	const void *mod = info->hdr;
-
+	bool mangled_module = flags & (MODULE_INIT_IGNORE_MODVERSIONS |
+				       MODULE_INIT_IGNORE_VERMAGIC);
 	/*
-	 * Require flags == 0, as a module with version information
-	 * removed is no longer the module that was signed
+	 * Do not allow mangled modules as a module with version information
+	 * removed is no longer the module that was signed.
 	 */
-	if (flags == 0 &&
+	if (!mangled_module &&
 	    info->len > markerlen &&
 	    memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
 		/* We truncate the module to discard the signature */
@@ -3174,9 +3174,12 @@ out:
 	return err;
 }
 
-static void free_copy(struct load_info *info)
+static void free_copy(struct load_info *info, int flags)
 {
-	vfree(info->hdr);
+	if (flags & MODULE_INIT_COMPRESSED_FILE)
+		module_decompress_cleanup(info);
+	else
+		vfree(info->hdr);
 }
 
 static int rewrite_section_headers(struct load_info *info, int flags)
@@ -4125,7 +4128,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
 	}
 
 	/* Get rid of temporary copy. */
-	free_copy(info);
+	free_copy(info, flags);
 
 	/* Done! */
 	trace_module_load(mod);
@@ -4174,7 +4177,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
 
 	module_deallocate(mod, info);
  free_copy:
-	free_copy(info);
+	free_copy(info, flags);
 	return err;
 }
 
@@ -4201,7 +4204,8 @@ SYSCALL_DEFINE3(init_module, void __user *, umod,
 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
 {
 	struct load_info info = { };
-	void *hdr = NULL;
+	void *buf = NULL;
+	int len;
 	int err;
 
 	err = may_init_module();
@@ -4211,15 +4215,24 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
 	pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
 
 	if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
-		      |MODULE_INIT_IGNORE_VERMAGIC))
+		      |MODULE_INIT_IGNORE_VERMAGIC
+		      |MODULE_INIT_COMPRESSED_FILE))
 		return -EINVAL;
 
-	err = kernel_read_file_from_fd(fd, 0, &hdr, INT_MAX, NULL,
+	len = kernel_read_file_from_fd(fd, 0, &buf, INT_MAX, NULL,
 				       READING_MODULE);
-	if (err < 0)
-		return err;
-	info.hdr = hdr;
-	info.len = err;
+	if (len < 0)
+		return len;
+
+	if (flags & MODULE_INIT_COMPRESSED_FILE) {
+		err = module_decompress(&info, buf, len);
+		vfree(buf); /* compressed data is no longer needed */
+		if (err)
+			return err;
+	} else {
+		info.hdr = buf;
+		info.len = len;
+	}
 
 	return load_module(&info, uargs, flags);
 }