Commit 046462ab authored by Sean Finney's avatar Sean Finney Committed by Steve French
Browse files

cifs: Simplify handling of submount options in cifs_mount. 



With CONFIG_DFS_UPCALL enabled, maintain the submount options in
cifs_sb->mountdata, simplifying the code just a bit as well as making
corner-case allocation problems less likely.

Reviewed-by: default avatarJeff Layton <jlayton@redhat.com>
Signed-off-by: default avatarSean Finney <seanius@seanius.net>
Signed-off-by: default avatarPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: default avatarSteve French <sfrench@us.ibm.com>
parent b946845a

fs/cifs/connect.c

+11 −13
Original line number Diff line number Diff line
@@ -2788,9 +2788,9 @@ build_unc_path_to_root(const struct smb_vol *volume_info, 
/*

 * Perform a dfs referral query for a share and (optionally) prefix

 *

 * If a referral is found, mount_data will be set to point at a newly

 * allocated string containing updated options for the submount.

 * Otherwise it will be left untouched.

 * If a referral is found, cifs_sb->mountdata will be (re-)allocated

 * to a string containing updated options for the submount.  Otherwise it

 * will be left untouched.

 *

 * Returns the rc from get_dfs_path to the caller, which can be used to

 * determine whether there were referrals.
@@ -2798,7 +2798,7 @@ build_unc_path_to_root(const struct smb_vol *volume_info, 
static int

expand_dfs_referral(int xid, struct cifsSesInfo *pSesInfo,

		    struct smb_vol *volume_info, struct cifs_sb_info *cifs_sb,

		    char **mount_data, int check_prefix)

		    int check_prefix)

{

	int rc;

	unsigned int num_referrals = 0;
@@ -2826,11 +2826,14 @@ expand_dfs_referral(int xid, struct cifsSesInfo *pSesInfo, 
		free_dfs_info_array(referrals, num_referrals);

		kfree(fake_devname);



		if (cifs_sb->mountdata != NULL)

			kfree(cifs_sb->mountdata);



		if (IS_ERR(mdata)) {

			rc = PTR_ERR(mdata);

			mdata = NULL;

		}

		*mount_data = mdata;

		cifs_sb->mountdata = mdata;

	}

	kfree(full_path);

	return rc;
@@ -2853,6 +2856,7 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb, 
#ifdef CONFIG_CIFS_DFS_UPCALL

	int referral_walks_count = 0;

try_mount_again:

	mount_data = cifs_sb->mountdata;



	/* cleanup activities if we're chasing a referral */

	if (referral_walks_count) {
@@ -2986,7 +2990,7 @@ remote_path_check: 
	 */

	if (referral_walks_count == 0) {

		int refrc = expand_dfs_referral(xid, pSesInfo, volume_info,

						cifs_sb, &mount_data, false);

						cifs_sb, false);

		if (!refrc) {

			referral_walks_count++;

			goto try_mount_again;
@@ -3028,17 +3032,13 @@ remote_path_check: 
			convert_delimiter(cifs_sb->prepath,

					CIFS_DIR_SEP(cifs_sb));



		if (mount_data != mount_data_global)

			kfree(mount_data);



		rc = expand_dfs_referral(xid, pSesInfo, volume_info, cifs_sb,

					 &mount_data, true);

					 true);



		if (!rc) {

			referral_walks_count++;

			goto try_mount_again;

		}

		mount_data = NULL;

		goto mount_fail_check;

#else /* No DFS support, return error on mount */

		rc = -EOPNOTSUPP;
@@ -3072,8 +3072,6 @@ remote_path_check: 
mount_fail_check:

	/* on error free sesinfo and tcon struct if needed */

	if (rc) {

		if (mount_data != mount_data_global)

			kfree(mount_data);

		/* If find_unc succeeded then rc == 0 so we can not end */

		/* up accidentally freeing someone elses tcon struct */

		if (tcon)

CRA Git | Maintained and supported by SUSTech CRA and CCSE