diff options
| -rw-r--r-- | fs/devpts/inode.c | 100 |
1 files changed, 22 insertions, 78 deletions
diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c index fb4da9d8913..70013dd8ec7 100644 --- a/fs/devpts/inode.c +++ b/fs/devpts/inode.c @@ -322,60 +322,21 @@ static int compare_init_pts_sb(struct super_block *s, void *p) } /* - * Safely parse the mount options in @data and update @opts. - * - * devpts ends up parsing options two times during mount, due to the - * two modes of operation it supports. The first parse occurs in - * devpts_get_sb() when determining the mode (single-instance or - * multi-instance mode). The second parse happens in devpts_remount() - * or new_pts_mount() depending on the mode. - * - * Parsing of options modifies the @data making subsequent parsing - * incorrect. So make a local copy of @data and parse it. - * - * Return: 0 On success, -errno on error - */ -static int safe_parse_mount_options(void *data, struct pts_mount_opts *opts) -{ - int rc; - void *datacp; - - if (!data) - return 0; - - /* Use kstrdup() ? */ - datacp = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!datacp) - return -ENOMEM; - - memcpy(datacp, data, PAGE_SIZE); - rc = parse_mount_options((char *)datacp, PARSE_MOUNT, opts); - kfree(datacp); - - return rc; -} - -/* * Mount a new (private) instance of devpts. PTYs created in this * instance are independent of the PTYs in other devpts instances. */ static int new_pts_mount(struct file_system_type *fs_type, int flags, - void *data, struct vfsmount *mnt) + void *data, struct pts_mount_opts *opts, struct vfsmount *mnt) { int err; struct pts_fs_info *fsi; - struct pts_mount_opts *opts; err = get_sb_nodev(fs_type, flags, data, devpts_fill_super, mnt); if (err) return err; fsi = DEVPTS_SB(mnt->mnt_sb); - opts = &fsi->mount_opts; - - err = parse_mount_options(data, PARSE_MOUNT, opts); - if (err) - goto fail; + memcpy(&fsi->mount_opts, opts, sizeof(opts)); err = mknod_ptmx(mnt->mnt_sb); if (err) @@ -391,28 +352,6 @@ fail: } /* - * Check if 'newinstance' mount option was specified in @data. - * - * Return: -errno on error (eg: invalid mount options specified) - * : 1 if 'newinstance' mount option was specified - * : 0 if 'newinstance' mount option was NOT specified - */ -static int is_new_instance_mount(void *data) -{ - int rc; - struct pts_mount_opts opts; - - if (!data) - return 0; - - rc = safe_parse_mount_options(data, &opts); - if (!rc) - rc = opts.newinstance; - - return rc; -} - -/* * get_init_pts_sb() * * This interface is needed to support multiple namespace semantics in @@ -434,10 +373,9 @@ static int is_new_instance_mount(void *data) * presence of the private namespace (i.e 'newinstance') super-blocks. */ static int get_init_pts_sb(struct file_system_type *fs_type, int flags, - void *data, struct vfsmount *mnt) + void *data, struct pts_mount_opts *opts, struct vfsmount *mnt) { struct super_block *s; - struct pts_mount_opts *opts; struct pts_fs_info *fsi; int error; @@ -455,11 +393,12 @@ static int get_init_pts_sb(struct file_system_type *fs_type, int flags, } s->s_flags |= MS_ACTIVE; } - fsi = DEVPTS_SB(s); - opts = &fsi->mount_opts; - parse_mount_options(data, PARSE_REMOUNT, opts); simple_set_mnt(mnt, s); + + fsi = DEVPTS_SB(mnt->mnt_sb); + memcpy(&fsi->mount_opts, opts, sizeof(opts)); + return 0; } @@ -469,11 +408,11 @@ static int get_init_pts_sb(struct file_system_type *fs_type, int flags, * kernel still allows multiple-instances. */ static int init_pts_mount(struct file_system_type *fs_type, int flags, - void *data, struct vfsmount *mnt) + void *data, struct pts_mount_opts *opts, struct vfsmount *mnt) { int err; - err = get_init_pts_sb(fs_type, flags, data, mnt); + err = get_init_pts_sb(fs_type, flags, data, opts, mnt); if (err) return err; @@ -490,17 +429,22 @@ static int init_pts_mount(struct file_system_type *fs_type, int flags, static int devpts_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, struct vfsmount *mnt) { - int new; - - new = is_new_instance_mount(data); - if (new < 0) - return new; + int error; + struct pts_mount_opts opts; - if (new) - return new_pts_mount(fs_type, flags, data, mnt); + memset(&opts, 0, sizeof(opts)); + if (data) { + error = parse_mount_options(data, PARSE_MOUNT, &opts); + if (error) + return error; + } - return init_pts_mount(fs_type, flags, data, mnt); + if (opts.newinstance) + return new_pts_mount(fs_type, flags, data, &opts, mnt); + else + return init_pts_mount(fs_type, flags, data, &opts, mnt); } + #else /* * This supports only the legacy single-instance semantics (no |