On Fri, Sep 17, 2021 at 09:13:23AM -0400, Vivek Goyal wrote:
> --- redhat-linux.orig/init/do_mounts.c 2021-09-15 08:46:33.801689806 -0400
> +++ redhat-linux/init/do_mounts.c 2021-09-17 08:44:40.781430167 -0400
> @@ -338,20 +338,19 @@ __setup("rootflags=", root_data_setup);
> __setup("rootfstype=", fs_names_setup);
> __setup("rootdelay=", root_delay_setup);
>
> -static int __init split_fs_names(char *page, char *names)
> +/* This can return zero length strings. Caller should check */
> +static int __init split_fs_names(char *page, size_t size, char *names)
> {
> - int count = 0;
> + int count = 1;
> char *p = page;
>
> - strcpy(p, root_fs_names);
> + strlcpy(p, root_fs_names, size);
> while (*p++) {
> - if (p[-1] == ',')
> + if (p[-1] == ',') {
> p[-1] = '\0';
> + count++;
> + }
> }
> - *p = '\0';
> -
> - for (p = page; *p; p += strlen(p)+1)
> - count++;
>
> return count;
> }
> @@ -404,12 +403,16 @@ void __init mount_block_root(char *name,
> scnprintf(b, BDEVNAME_SIZE, "unknown-block(%u,%u)",
> MAJOR(ROOT_DEV), MINOR(ROOT_DEV));
> if (root_fs_names)
> - num_fs = split_fs_names(fs_names, root_fs_names);
> + num_fs = split_fs_names(fs_names, PAGE_SIZE, root_fs_names);
> else
> num_fs = list_bdev_fs_names(fs_names, PAGE_SIZE);
> retry:
> for (i = 0, p = fs_names; i < num_fs; i++, p += strlen(p)+1) {
> - int err = do_mount_root(name, p, flags, root_mount_data);
> + int err;
> +
> + if (!*p)
> + continue;
> + err = do_mount_root(name, p, flags, root_mount_data);
> switch (err) {
> case 0:
> goto out;
> @@ -543,10 +546,12 @@ static int __init mount_nodev_root(void)
> fs_names = (void *)__get_free_page(GFP_KERNEL);
> if (!fs_names)
> return -EINVAL;
> - num_fs = split_fs_names(fs_names, root_fs_names);
> + num_fs = split_fs_names(fs_names, PAGE_SIZE, root_fs_names);
>
> for (i = 0, fstype = fs_names; i < num_fs;
> i++, fstype += strlen(fstype) + 1) {
> + if (!*fstype)
> + continue;
> if (!fs_is_nodev(fstype))
> continue;
> err = do_mount_root(root_device_name, fstype, root_mountflags,
Applied.
