Commit b56bce50 authored by Paulo Alcantara's avatar Paulo Alcantara Committed by Steve French
Browse files

cifs: set DFS root session in cifs_get_smb_ses() 



Set the DFS root session pointer earlier when creating a new SMB
session to prevent racing with smb2_reconnect(), cifs_reconnect_tcon()
and DFS cache refresher.

Signed-off-by: default avatarPaulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org # 6.2
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 05ce0448

fs/cifs/cifs_dfs_ref.c

+1 −0
Original line number Diff line number Diff line
@@ -179,6 +179,7 @@ static struct vfsmount *cifs_dfs_do_automount(struct path *path) 
	tmp.source = full_path;

	tmp.leaf_fullpath = NULL;

	tmp.UNC = tmp.prepath = NULL;

	tmp.dfs_root_ses = NULL;



	rc = smb3_fs_context_dup(ctx, &tmp);

	if (rc) {

fs/cifs/cifsglob.h

+0 −1
Original line number Diff line number Diff line
@@ -1749,7 +1749,6 @@ struct cifs_mount_ctx { 
	struct TCP_Server_Info *server;

	struct cifs_ses *ses;

	struct cifs_tcon *tcon;

	struct cifs_ses *root_ses;

	uuid_t mount_id;

	char *origin_fullpath, *leaf_fullpath;

};

fs/cifs/connect.c

+1 −0
Original line number Diff line number Diff line
@@ -2229,6 +2229,7 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx) 
	 * need to lock before changing something in the session.

	 */

	spin_lock(&cifs_tcp_ses_lock);

	ses->dfs_root_ses = ctx->dfs_root_ses;

	list_add(&ses->smb_ses_list, &server->smb_ses_list);

	spin_unlock(&cifs_tcp_ses_lock);

fs/cifs/dfs.c

+8 −11
Original line number Diff line number Diff line
@@ -95,25 +95,22 @@ static int get_session(struct cifs_mount_ctx *mnt_ctx, const char *full_path) 
	ctx->leaf_fullpath = (char *)full_path;

	rc = cifs_mount_get_session(mnt_ctx);

	ctx->leaf_fullpath = NULL;

	if (!rc) {

		struct cifs_ses *ses = mnt_ctx->ses;



		mutex_lock(&ses->session_mutex);

		ses->dfs_root_ses = mnt_ctx->root_ses;

		mutex_unlock(&ses->session_mutex);

	}

	return rc;

}



static void set_root_ses(struct cifs_mount_ctx *mnt_ctx)

{

	if (mnt_ctx->ses) {

	struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;

	struct cifs_ses *ses = mnt_ctx->ses;



	if (ses) {

		spin_lock(&cifs_tcp_ses_lock);

		mnt_ctx->ses->ses_count++;

		ses->ses_count++;

		spin_unlock(&cifs_tcp_ses_lock);

		dfs_cache_add_refsrv_session(&mnt_ctx->mount_id, mnt_ctx->ses);

		dfs_cache_add_refsrv_session(&mnt_ctx->mount_id, ses);

	}

	mnt_ctx->root_ses = mnt_ctx->ses;

	ctx->dfs_root_ses = mnt_ctx->ses;

}



static int get_dfs_conn(struct cifs_mount_ctx *mnt_ctx, const char *ref_path, const char *full_path,
@@ -260,7 +257,7 @@ int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs) 
	rc = get_session(mnt_ctx, NULL);

	if (rc)

		return rc;

	mnt_ctx->root_ses = mnt_ctx->ses;

	ctx->dfs_root_ses = mnt_ctx->ses;

	/*

	 * If called with 'nodfs' mount option, then skip DFS resolving.  Otherwise unconditionally

	 * try to get an DFS referral (even cached) to determine whether it is an DFS mount.

fs/cifs/dfs.h

+2 −1
Original line number Diff line number Diff line
@@ -22,9 +22,10 @@ static inline char *dfs_get_path(struct cifs_sb_info *cifs_sb, const char *path) 
static inline int dfs_get_referral(struct cifs_mount_ctx *mnt_ctx, const char *path,

				   struct dfs_info3_param *ref, struct dfs_cache_tgt_list *tl)

{

	struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;

	struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;



	return dfs_cache_find(mnt_ctx->xid, mnt_ctx->root_ses, cifs_sb->local_nls,

	return dfs_cache_find(mnt_ctx->xid, ctx->dfs_root_ses, cifs_sb->local_nls,

			      cifs_remap(cifs_sb), path, ref, tl);

}