initrd: use do_mount() instead of ksys_mount() (d4440aac) · Commits · 戴 / test

All three calls to ksys_mount() in initrd-related kernel code can be switched over to do_mount(): - the first and third arguments are const strings in the kernel, and do not need to be copied over from userspace; - the fifth argument is NULL, and therefore no page needs to be, copied over from userspace; - the second and fourth argument are passed through anyway. Signed-off-by:

Dominik Brodowski <linux@dominikbrodowski.net>

init/do_mounts_initrd.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -54,7 +54,7 @@ static int init_linuxrc(struct subprocess_info info, struct cred new)
		ksys_dup(0);
		/* move initrd over / and chdir/chroot in initrd root */
		ksys_chdir("/root");
		ksys_mount(".", "/", NULL, MS_MOVE, NULL);
		do_mount(".", "/", NULL, MS_MOVE, NULL);
		ksys_chroot(".");
		ksys_setsid();
		return 0;
		@@ -89,7 +89,7 @@ static void __init handle_initrd(void)
		current->flags &= ~PF_FREEZER_SKIP;

		/* move initrd to rootfs' /old */
		ksys_mount("..", ".", NULL, MS_MOVE, NULL);
		do_mount("..", ".", NULL, MS_MOVE, NULL);
		/* switch root and cwd back to / of rootfs */
		ksys_chroot("..");

		@@ -103,7 +103,7 @@ static void __init handle_initrd(void)
		mount_root();

		printk(KERN_NOTICE "Trying to move old root to /initrd ... ");
		error = ksys_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL);
		error = do_mount("/old", "/root/initrd", NULL, MS_MOVE, NULL);
		if (!error)
		printk("okay\n");
		else {

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