6.1-stable review patch. If anyone has any objections, please let me know.
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From: Paulo Alcantara pc@cjr.nz
[ Upstream commit 9fd29a5bae6e8f94b410374099a6fddb253d2d5f ]
Use filesystem context support to handle dfs links.
Signed-off-by: Paulo Alcantara (SUSE) pc@cjr.nz Signed-off-by: Steve French stfrench@microsoft.com Stable-dep-of: efc0b0bcffcb ("smb: propagate error code of extract_sharename()") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/smb/client/cifs_dfs_ref.c | 100 ++++++++++++++--------------------- 1 file changed, 40 insertions(+), 60 deletions(-)
diff --git a/fs/smb/client/cifs_dfs_ref.c b/fs/smb/client/cifs_dfs_ref.c index b0864da9ef434..020e71fe1454e 100644 --- a/fs/smb/client/cifs_dfs_ref.c +++ b/fs/smb/client/cifs_dfs_ref.c @@ -258,61 +258,23 @@ char *cifs_compose_mount_options(const char *sb_mountdata, goto compose_mount_options_out; }
-/** - * cifs_dfs_do_mount - mounts specified path using DFS full path - * - * Always pass down @fullpath to smb3_do_mount() so we can use the root server - * to perform failover in case we failed to connect to the first target in the - * referral. - * - * @mntpt: directory entry for the path we are trying to automount - * @cifs_sb: parent/root superblock - * @fullpath: full path in UNC format - */ -static struct vfsmount *cifs_dfs_do_mount(struct dentry *mntpt, - struct cifs_sb_info *cifs_sb, - const char *fullpath) -{ - struct vfsmount *mnt; - char *mountdata; - char *devname; - - devname = kstrdup(fullpath, GFP_KERNEL); - if (!devname) - return ERR_PTR(-ENOMEM); - - convert_delimiter(devname, '/'); - - /* TODO: change to call fs_context_for_mount(), fill in context directly, call fc_mount */ - - /* See afs_mntpt_do_automount in fs/afs/mntpt.c for an example */ - - /* strip first '' from fullpath */ - mountdata = cifs_compose_mount_options(cifs_sb->ctx->mount_options, - fullpath + 1, NULL, NULL); - if (IS_ERR(mountdata)) { - kfree(devname); - return (struct vfsmount *)mountdata; - } - - mnt = vfs_submount(mntpt, &cifs_fs_type, devname, mountdata); - kfree(mountdata); - kfree(devname); - return mnt; -} - /* * Create a vfsmount that we can automount */ -static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt) +static struct vfsmount *cifs_dfs_do_automount(struct path *path) { + int rc; + struct dentry *mntpt = path->dentry; + struct fs_context *fc; struct cifs_sb_info *cifs_sb; - void *page; + void *page = NULL; + struct smb3_fs_context *ctx, *cur_ctx; + struct smb3_fs_context tmp; char *full_path; struct vfsmount *mnt;
- cifs_dbg(FYI, "in %s\n", __func__); - BUG_ON(IS_ROOT(mntpt)); + if (IS_ROOT(mntpt)) + return ERR_PTR(-ESTALE);
/* * The MSDFS spec states that paths in DFS referral requests and @@ -321,29 +283,47 @@ static struct vfsmount *cifs_dfs_do_automount(struct dentry *mntpt) * gives us the latter, so we must adjust the result. */ cifs_sb = CIFS_SB(mntpt->d_sb); - if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) { - mnt = ERR_PTR(-EREMOTE); - goto cdda_exit; - } + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) + return ERR_PTR(-EREMOTE); + + cur_ctx = cifs_sb->ctx; + + fc = fs_context_for_submount(path->mnt->mnt_sb->s_type, mntpt); + if (IS_ERR(fc)) + return ERR_CAST(fc); + + ctx = smb3_fc2context(fc);
page = alloc_dentry_path(); /* always use tree name prefix */ full_path = build_path_from_dentry_optional_prefix(mntpt, page, true); if (IS_ERR(full_path)) { mnt = ERR_CAST(full_path); - goto free_full_path; + goto out; }
- convert_delimiter(full_path, '\'); + convert_delimiter(full_path, '/'); cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
- mnt = cifs_dfs_do_mount(mntpt, cifs_sb, full_path); - cifs_dbg(FYI, "%s: cifs_dfs_do_mount:%s , mnt:%p\n", __func__, full_path + 1, mnt); + tmp = *cur_ctx; + tmp.source = full_path; + tmp.UNC = tmp.prepath = NULL; + + rc = smb3_fs_context_dup(ctx, &tmp); + if (rc) { + mnt = ERR_PTR(rc); + goto out; + } + + rc = smb3_parse_devname(full_path, ctx); + if (!rc) + mnt = fc_mount(fc); + else + mnt = ERR_PTR(rc);
-free_full_path: +out: + put_fs_context(fc); free_dentry_path(page); -cdda_exit: - cifs_dbg(FYI, "leaving %s\n" , __func__); return mnt; }
@@ -354,9 +334,9 @@ struct vfsmount *cifs_dfs_d_automount(struct path *path) { struct vfsmount *newmnt;
- cifs_dbg(FYI, "in %s\n", __func__); + cifs_dbg(FYI, "%s: %pd\n", __func__, path->dentry);
- newmnt = cifs_dfs_do_automount(path->dentry); + newmnt = cifs_dfs_do_automount(path); if (IS_ERR(newmnt)) { cifs_dbg(FYI, "leaving %s [automount failed]\n" , __func__); return newmnt;