write in 30M

hc

2024-02-20 ea08eeccae9297f7aabd2ef7f0c2517ac4549acc

 kernel/fs/binfmt_misc.c
..
..
@@ -1,3 +1,4 @@
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+// SPDX-License-Identifier: GPL-2.0-only
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 /*
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  * binfmt_misc.c
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  *
..
..
@@ -22,6 +23,7 @@
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 #include <linux/pagemap.h>
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 #include <linux/namei.h>
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 #include <linux/mount.h>
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+#include <linux/fs_context.h>
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 #include <linux/syscalls.h>
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 #include <linux/fs.h>
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 #include <linux/uaccess.h>
..
..
@@ -42,10 +44,10 @@
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 static int enabled = 1;
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45
 
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 enum {Enabled, Magic};
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-#define MISC_FMT_PRESERVE_ARGV0 (1 << 31)
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-#define MISC_FMT_OPEN_BINARY (1 << 30)
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-#define MISC_FMT_CREDENTIALS (1 << 29)
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-#define MISC_FMT_OPEN_FILE (1 << 28)
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+#define MISC_FMT_PRESERVE_ARGV0 (1UL << 31)
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+#define MISC_FMT_OPEN_BINARY (1UL << 30)
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+#define MISC_FMT_CREDENTIALS (1UL << 29)
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+#define MISC_FMT_OPEN_FILE (1UL << 28)
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 typedef struct {
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 	struct list_head list;
..
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@@ -132,7 +134,6 @@
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 	Node *fmt;
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 	struct file *interp_file = NULL;
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 	int retval;
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-	int fd_binary = -1;
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 	retval = -ENOEXEC;
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 	if (!enabled)
..
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@@ -158,51 +159,25 @@
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 			goto ret;
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 	}
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161
 
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-	if (fmt->flags & MISC_FMT_OPEN_BINARY) {
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+	if (fmt->flags & MISC_FMT_OPEN_BINARY)
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+		bprm->have_execfd = 1;
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-		/* if the binary should be opened on behalf of the
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-		 * interpreter than keep it open and assign descriptor
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-		 * to it
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-		 */
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-		fd_binary = get_unused_fd_flags(0);
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-		if (fd_binary < 0) {
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-			retval = fd_binary;
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-			goto ret;
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-		}
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-		fd_install(fd_binary, bprm->file);
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-
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-		/* if the binary is not readable than enforce mm->dumpable=0
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-		   regardless of the interpreter's permissions */
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-		would_dump(bprm, bprm->file);
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-
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-		allow_write_access(bprm->file);
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-		bprm->file = NULL;
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-
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-		/* mark the bprm that fd should be passed to interp */
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-		bprm->interp_flags |= BINPRM_FLAGS_EXECFD;
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-		bprm->interp_data = fd_binary;
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-
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-	} else {
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-		allow_write_access(bprm->file);
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-		fput(bprm->file);
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-		bprm->file = NULL;
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-	}
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 	/* make argv[1] be the path to the binary */
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-	retval = copy_strings_kernel(1, &bprm->interp, bprm);
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+	retval = copy_string_kernel(bprm->interp, bprm);
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 	if (retval < 0)
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-		goto error;
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+		goto ret;
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 	bprm->argc++;
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170
 
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 	/* add the interp as argv[0] */
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-	retval = copy_strings_kernel(1, &fmt->interpreter, bprm);
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+	retval = copy_string_kernel(fmt->interpreter, bprm);
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 	if (retval < 0)
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-		goto error;
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+		goto ret;
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 	bprm->argc++;
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 	/* Update interp in case binfmt_script needs it. */
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 	retval = bprm_change_interp(fmt->interpreter, bprm);
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 	if (retval < 0)
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-		goto error;
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+		goto ret;
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 	if (fmt->flags & MISC_FMT_OPEN_FILE) {
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 		interp_file = file_clone_open(fmt->interp_file);
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@@ -213,38 +188,16 @@
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 	}
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 	retval = PTR_ERR(interp_file);
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190
 	if (IS_ERR(interp_file))
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-		goto error;
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+		goto ret;
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192
 
218
-	bprm->file = interp_file;
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-	if (fmt->flags & MISC_FMT_CREDENTIALS) {
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-		loff_t pos = 0;
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+	bprm->interpreter = interp_file;
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+	if (fmt->flags & MISC_FMT_CREDENTIALS)
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+		bprm->execfd_creds = 1;
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196
 
222
-		/*
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-		 * No need to call prepare_binprm(), it's already been
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-		 * done.  bprm->buf is stale, update from interp_file.
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-		 */
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-		memset(bprm->buf, 0, BINPRM_BUF_SIZE);
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-		retval = kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE,
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-				&pos);
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-	} else
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-		retval = prepare_binprm(bprm);
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-
232
-	if (retval < 0)
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-		goto error;
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-
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-	retval = search_binary_handler(bprm);
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-	if (retval < 0)
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-		goto error;
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-
197
+	retval = 0;
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198
 ret:
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 	dput(fmt->dentry);
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200
 	return retval;
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-error:
243
-	if (fd_binary > 0)
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-		ksys_close(fd_binary);
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-	bprm->interp_flags = 0;
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-	bprm->interp_data = 0;
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-	goto ret;
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201
 }
249
202
 
250
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 /* Command parsers */
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..
@@ -819,7 +772,7 @@
819
772
 	.evict_inode	= bm_evict_inode,
820
773
 };
821
774
 
822
-static int bm_fill_super(struct super_block *sb, void *data, int silent)
775
+static int bm_fill_super(struct super_block *sb, struct fs_context *fc)
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 {
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777
 	int err;
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 	static const struct tree_descr bm_files[] = {
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..
@@ -834,10 +787,19 @@
834
787
 	return err;
835
788
 }
836
789
 
837
-static struct dentry *bm_mount(struct file_system_type *fs_type,
838
-	int flags, const char *dev_name, void *data)
790
+static int bm_get_tree(struct fs_context *fc)
839
791
 {
840
-	return mount_single(fs_type, flags, data, bm_fill_super);
792
+	return get_tree_single(fc, bm_fill_super);
793
+}
794
+
795
+static const struct fs_context_operations bm_context_ops = {
796
+	.get_tree	= bm_get_tree,
797
+};
798
+
799
+static int bm_init_fs_context(struct fs_context *fc)
800
+{
801
+	fc->ops = &bm_context_ops;
802
+	return 0;
841
803
 }
842
804
 
843
805
 static struct linux_binfmt misc_format = {
..
..
@@ -848,7 +810,7 @@
848
810
 static struct file_system_type bm_fs_type = {
849
811
 	.owner		= THIS_MODULE,
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812
 	.name		= "binfmt_misc",
851
-	.mount		= bm_mount,
813
+	.init_fs_context = bm_init_fs_context,
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814
 	.kill_sb	= kill_litter_super,
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815
 };
854
816
 MODULE_ALIAS_FS("binfmt_misc");
..
..
@@ -870,3 +832,4 @@
870
832
 core_initcall(init_misc_binfmt);
871
833
 module_exit(exit_misc_binfmt);
872
834
 MODULE_LICENSE("GPL");
835
+MODULE_IMPORT_NS(ANDROID_GKI_VFS_EXPORT_ONLY);