Commit 9ccecae8 authored by Ronnie Sahlberg's avatar Ronnie Sahlberg Committed by Steve French
Browse files

cifs: we do not allow changing username/password/unc/... during remount 



Signed-off-by: default avatarRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent d6a78783

fs/cifs/cifsfs.c

+1 −1
Original line number Diff line number Diff line
@@ -493,7 +493,7 @@ cifs_show_options(struct seq_file *s, struct dentry *root) 


	if (tcon->no_lease)

		seq_puts(s, ",nolease");

	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER)

	if (cifs_sb->ctx->multiuser)

		seq_puts(s, ",multiuser");

	else if (tcon->ses->user_name)

		seq_show_option(s, "username", tcon->ses->user_name);

fs/cifs/fs_context.c

+50 −3
Original line number Diff line number Diff line
@@ -632,10 +632,51 @@ static int smb3_verify_reconfigure_ctx(struct smb3_fs_context *new_ctx, 
		cifs_dbg(VFS, "can not change sec during remount\n");

		return -EINVAL;

	}

	if (new_ctx->multiuser != old_ctx->multiuser) {

		cifs_dbg(VFS, "can not change multiuser during remount\n");

		return -EINVAL;

	}

	if (new_ctx->UNC &&

	    (!old_ctx->UNC || strcmp(new_ctx->UNC, old_ctx->UNC))) {

		cifs_dbg(VFS, "can not change UNC during remount\n");

		return -EINVAL;

	}

	if (new_ctx->username &&

	    (!old_ctx->username || strcmp(new_ctx->username, old_ctx->username))) {

		cifs_dbg(VFS, "can not change username during remount\n");

		return -EINVAL;

	}

	if (new_ctx->password &&

	    (!old_ctx->password || strcmp(new_ctx->password, old_ctx->password))) {

		cifs_dbg(VFS, "can not change password during remount\n");

		return -EINVAL;

	}

	if (new_ctx->domainname &&

	    (!old_ctx->domainname || strcmp(new_ctx->domainname, old_ctx->domainname))) {

		cifs_dbg(VFS, "can not change domainname during remount\n");

		return -EINVAL;

	}

	if (new_ctx->nodename &&

	    (!old_ctx->nodename || strcmp(new_ctx->nodename, old_ctx->nodename))) {

		cifs_dbg(VFS, "can not change nodename during remount\n");

		return -EINVAL;

	}

	if (new_ctx->iocharset &&

	    (!old_ctx->iocharset || strcmp(new_ctx->iocharset, old_ctx->iocharset))) {

		cifs_dbg(VFS, "can not change iocharset during remount\n");

		return -EINVAL;

	}



	return 0;

}



#define STEAL_STRING(cifs_sb, ctx, field)				\

do {									\

	kfree(ctx->field);						\

	ctx->field = cifs_sb->ctx->field;				\

	cifs_sb->ctx->field = NULL;					\

} while (0)



static int smb3_reconfigure(struct fs_context *fc)

{

	struct smb3_fs_context *ctx = smb3_fc2context(fc);
@@ -648,10 +689,16 @@ static int smb3_reconfigure(struct fs_context *fc) 
		return rc;



	/*

	 * Steal the UNC from the old and to be destroyed context.

	 * We can not change UNC/username/password/domainname/nodename/iocharset

	 * during reconnect so ignore what we have in the new context and

	 * just use what we already have in cifs_sb->ctx.

	 */

	ctx->UNC = cifs_sb->ctx->UNC;

	cifs_sb->ctx->UNC = NULL;

	STEAL_STRING(cifs_sb, ctx, UNC);

	STEAL_STRING(cifs_sb, ctx, username);

	STEAL_STRING(cifs_sb, ctx, password);

	STEAL_STRING(cifs_sb, ctx, domainname);

	STEAL_STRING(cifs_sb, ctx, nodename);

	STEAL_STRING(cifs_sb, ctx, iocharset);



	smb3_cleanup_fs_context_contents(cifs_sb->ctx);

	rc = smb3_fs_context_dup(cifs_sb->ctx, ctx);

fs/cifs/fs_context.h

+1 −1
Original line number Diff line number Diff line
@@ -149,7 +149,6 @@ struct smb3_fs_context { 
	bool uid_specified;

	bool gid_specified;

	bool sloppy;

	char *nodename;

	bool got_ip;

	bool got_version;

	bool got_rsize;
@@ -161,6 +160,7 @@ struct smb3_fs_context { 
	char *password;

	char *domainname;

	char *UNC;

	char *nodename;

	char *iocharset;  /* local code page for mapping to and from Unicode */

	char source_rfc1001_name[RFC1001_NAME_LEN_WITH_NULL]; /* clnt nb name */

	char target_rfc1001_name[RFC1001_NAME_LEN_WITH_NULL]; /* srvr nb name */