Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull trivial vfs updates from Al Viro:
"A few cleanups + Neil's namespace_unlock() optimization"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
exec: make prepare_bprm_creds static
genheaders: %-<width>s had been there since v6; %-*s - since v7
VFS: use synchronize_rcu_expedited() in namespace_unlock()
iov_iter: reduce code duplication

fs/exec.c

···
  * Or, if exec fails before, free_bprm() should release ->cred and
  * and unlock.
  */
-int prepare_bprm_creds(struct linux_binprm *bprm)
+static int prepare_bprm_creds(struct linux_binprm *bprm)
 {
 	if (mutex_lock_interruptible(&current->signal->cred_guard_mutex))
 		return -ERESTARTNOINTR;

fs/namespace.c

···
 	if (likely(hlist_empty(&head)))
 		return;
 
-	synchronize_rcu();
+	synchronize_rcu_expedited();
 
 	group_pin_kill(&head);
 }

include/linux/binfmts.h

···
 extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm);
 extern int copy_strings_kernel(int argc, const char *const *argv,
 			       struct linux_binprm *bprm);
-extern int prepare_bprm_creds(struct linux_binprm *bprm);
 extern void install_exec_creds(struct linux_binprm *bprm);
 extern void set_binfmt(struct linux_binfmt *new);
 extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);

lib/iov_iter.c

···
 	return bytes;
 }
 
+static __wsum csum_and_memcpy(void *to, const void *from, size_t len,
+			      __wsum sum, size_t off)
+{
+	__wsum next = csum_partial_copy_nocheck(from, to, len, 0);
+	return csum_block_add(sum, next, off);
+}
+
 static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes,
 				__wsum *csum, struct iov_iter *i)
 {
 	struct pipe_inode_info *pipe = i->pipe;
 	size_t n, r;
 	size_t off = 0;
-	__wsum sum = *csum, next;
+	__wsum sum = *csum;
 	int idx;
 
 	if (!sanity(i))
···
 	for ( ; n; idx = next_idx(idx, pipe), r = 0) {
 		size_t chunk = min_t(size_t, n, PAGE_SIZE - r);
 		char *p = kmap_atomic(pipe->bufs[idx].page);
-		next = csum_partial_copy_nocheck(addr, p + r, chunk, 0);
-		sum = csum_block_add(sum, next, off);
+		sum = csum_and_memcpy(p + r, addr, chunk, sum, off);
 		kunmap_atomic(p);
 		i->idx = idx;
 		i->iov_offset = r + chunk;
···
 		err ? v.iov_len : 0;
 	}), ({
 		char *p = kmap_atomic(v.bv_page);
-		next = csum_partial_copy_nocheck(p + v.bv_offset,
-						 (to += v.bv_len) - v.bv_len,
-						 v.bv_len, 0);
+		sum = csum_and_memcpy((to += v.bv_len) - v.bv_len,
+				      p + v.bv_offset, v.bv_len,
+				      sum, off);
 		kunmap_atomic(p);
-		sum = csum_block_add(sum, next, off);
 		off += v.bv_len;
 	}),({
-		next = csum_partial_copy_nocheck(v.iov_base,
-						 (to += v.iov_len) - v.iov_len,
-						 v.iov_len, 0);
-		sum = csum_block_add(sum, next, off);
+		sum = csum_and_memcpy((to += v.iov_len) - v.iov_len,
+				      v.iov_base, v.iov_len,
+				      sum, off);
 		off += v.iov_len;
 	})
 	)
···
 		0;
 	}), ({
 		char *p = kmap_atomic(v.bv_page);
-		next = csum_partial_copy_nocheck(p + v.bv_offset,
-						 (to += v.bv_len) - v.bv_len,
-						 v.bv_len, 0);
+		sum = csum_and_memcpy((to += v.bv_len) - v.bv_len,
+				      p + v.bv_offset, v.bv_len,
+				      sum, off);
 		kunmap_atomic(p);
-		sum = csum_block_add(sum, next, off);
 		off += v.bv_len;
 	}),({
-		next = csum_partial_copy_nocheck(v.iov_base,
-						 (to += v.iov_len) - v.iov_len,
-						 v.iov_len, 0);
-		sum = csum_block_add(sum, next, off);
+		sum = csum_and_memcpy((to += v.iov_len) - v.iov_len,
+				      v.iov_base, v.iov_len,
+				      sum, off);
 		off += v.iov_len;
 	})
 	)
···
 		err ? v.iov_len : 0;
 	}), ({
 		char *p = kmap_atomic(v.bv_page);
-		next = csum_partial_copy_nocheck((from += v.bv_len) - v.bv_len,
-						 p + v.bv_offset,
-						 v.bv_len, 0);
+		sum = csum_and_memcpy(p + v.bv_offset,
+				      (from += v.bv_len) - v.bv_len,
+				      v.bv_len, sum, off);
 		kunmap_atomic(p);
-		sum = csum_block_add(sum, next, off);
 		off += v.bv_len;
 	}),({
-		next = csum_partial_copy_nocheck((from += v.iov_len) - v.iov_len,
-						 v.iov_base,
-						 v.iov_len, 0);
-		sum = csum_block_add(sum, next, off);
+		sum = csum_and_memcpy(v.iov_base,
+				     (from += v.iov_len) - v.iov_len,
+				     v.iov_len, sum, off);
 		off += v.iov_len;
 	})
 	)

scripts/selinux/genheaders/genheaders.c

···
 #include "classmap.h"
 #include "initial_sid_to_string.h"
 
-#define max(x, y) (((int)(x) > (int)(y)) ? x : y)
-
 const char *progname;
 
 static void usage(void)
···
 
 int main(int argc, char *argv[])
 {
-	int i, j, k;
+	int i, j;
 	int isids_len;
 	FILE *fout;
-	const char *needle = "SOCKET";
-	char *substr;
 
 	progname = argv[0];
 
···
 
 	for (i = 0; secclass_map[i].name; i++) {
 		struct security_class_mapping *map = &secclass_map[i];
-		fprintf(fout, "#define SECCLASS_%s", map->name);
-		for (j = 0; j < max(1, 40 - strlen(map->name)); j++)
-			fprintf(fout, " ");
-		fprintf(fout, "%2d\n", i+1);
+		fprintf(fout, "#define SECCLASS_%-39s %2d\n", map->name, i+1);
 	}
 
 	fprintf(fout, "\n");
 
 	for (i = 1; i < isids_len; i++) {
 		const char *s = initial_sid_to_string[i];
-		fprintf(fout, "#define SECINITSID_%s", s);
-		for (j = 0; j < max(1, 40 - strlen(s)); j++)
-			fprintf(fout, " ");
-		fprintf(fout, "%2d\n", i);
+		fprintf(fout, "#define SECINITSID_%-39s %2d\n", s, i);
 	}
 	fprintf(fout, "\n#define SECINITSID_NUM %d\n", i-1);
 	fprintf(fout, "\nstatic inline bool security_is_socket_class(u16 kern_tclass)\n");
···
 	fprintf(fout, "\tbool sock = false;\n\n");
 	fprintf(fout, "\tswitch (kern_tclass) {\n");
 	for (i = 0; secclass_map[i].name; i++) {
+		static char s[] = "SOCKET";
 		struct security_class_mapping *map = &secclass_map[i];
-		substr = strstr(map->name, needle);
-		if (substr && strcmp(substr, needle) == 0)
+		int len = strlen(map->name), l = sizeof(s) - 1;
+		if (len >= l && memcmp(map->name + len - l, s, l) == 0)
 			fprintf(fout, "\tcase SECCLASS_%s:\n", map->name);
 	}
 	fprintf(fout, "\t\tsock = true;\n");
···
 
 	for (i = 0; secclass_map[i].name; i++) {
 		struct security_class_mapping *map = &secclass_map[i];
+		int len = strlen(map->name);
 		for (j = 0; map->perms[j]; j++) {
 			if (j >= 32) {
 				fprintf(stderr, "Too many permissions to fit into an access vector at (%s, %s).\n",
 					map->name, map->perms[j]);
 				exit(5);
 			}
-			fprintf(fout, "#define %s__%s", map->name,
-				map->perms[j]);
-			for (k = 0; k < max(1, 40 - strlen(map->name) - strlen(map->perms[j])); k++)
-				fprintf(fout, " ");
-			fprintf(fout, "0x%08xU\n", (1<<j));
+			fprintf(fout, "#define %s__%-*s 0x%08xU\n", map->name,
+				39-len, map->perms[j], 1U<<j);
 		}
 	}