Commit 7548e1da authored by Paulo Alcantara's avatar Paulo Alcantara Committed by Steve French
Browse files

cifs: handle RESP_GET_DFS_REFERRAL.PathConsumed in reconnect 



Use PathConsumed field when parsing prefixes of referral paths that
either match a cache entry or are a complete prefix path of an
existing entry.

Signed-off-by: default avatarPaulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: default avatarAurelien Aptel <aaptel@suse.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent a5293035

fs/cifs/cifsproto.h

+1 −2
Original line number Diff line number Diff line
@@ -617,8 +617,7 @@ int smb2_parse_query_directory(struct cifs_tcon *tcon, struct kvec *rsp_iov, 


struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server);

void cifs_put_tcp_super(struct super_block *sb);

int update_super_prepath(struct cifs_tcon *tcon, const char *prefix,

			 size_t prefix_len);

int update_super_prepath(struct cifs_tcon *tcon, char *prefix);



#ifdef CONFIG_CIFS_DFS_UPCALL

static inline int get_dfs_path(const unsigned int xid, struct cifs_ses *ses,

fs/cifs/connect.c

+11 −6
Original line number Diff line number Diff line
@@ -5547,6 +5547,7 @@ int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const stru 
	size_t tcp_host_len;

	const char *dfs_host;

	size_t dfs_host_len;

	char *share = NULL, *prefix = NULL;



	tree = kzalloc(MAX_TREE_SIZE, GFP_KERNEL);

	if (!tree)
@@ -5569,11 +5570,12 @@ int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const stru 
	extract_unc_hostname(server->hostname, &tcp_host, &tcp_host_len);



	for (it = dfs_cache_get_tgt_iterator(&tl); it; it = dfs_cache_get_next_tgt(&tl, it)) {

		const char *share, *prefix;

		size_t share_len, prefix_len;

		bool target_match;



		rc = dfs_cache_get_tgt_share(it, &share, &share_len, &prefix, &prefix_len);

		kfree(share);

		kfree(prefix);



		rc = dfs_cache_get_tgt_share(tcon->dfs_path + 1, it, &share, &prefix);

		if (rc) {

			cifs_dbg(VFS, "%s: failed to parse target share %d\n",

				 __func__, rc);
@@ -5600,13 +5602,13 @@ int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const stru 
		}



		if (tcon->ipc) {

			scnprintf(tree, MAX_TREE_SIZE, "\\\\%.*s\\IPC$", (int)share_len, share);

			scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", share);

			rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);

		} else {

			scnprintf(tree, MAX_TREE_SIZE, "\\%.*s", (int)share_len, share);

			scnprintf(tree, MAX_TREE_SIZE, "\\%s", share);

			rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);

			if (!rc) {

				rc = update_super_prepath(tcon, prefix, prefix_len);

				rc = update_super_prepath(tcon, prefix);

				break;

			}

		}
@@ -5614,6 +5616,9 @@ int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const stru 
			break;

	}



	kfree(share);

	kfree(prefix);



	if (!rc) {

		if (it)

			rc = dfs_cache_noreq_update_tgthint(tcon->dfs_path + 1, it);

fs/cifs/dfs_cache.c

+44 −13
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 


struct cache_dfs_tgt {

	char *name;

	int path_consumed;

	struct list_head list;

};
@@ -350,7 +351,7 @@ static inline struct timespec64 get_expire_time(int ttl) 
}



/* Allocate a new DFS target */

static struct cache_dfs_tgt *alloc_target(const char *name)

static struct cache_dfs_tgt *alloc_target(const char *name, int path_consumed)

{

	struct cache_dfs_tgt *t;
@@ -362,6 +363,7 @@ static struct cache_dfs_tgt *alloc_target(const char *name) 
		kfree(t);

		return ERR_PTR(-ENOMEM);

	}

	t->path_consumed = path_consumed;

	INIT_LIST_HEAD(&t->list);

	return t;

}
@@ -384,7 +386,7 @@ static int copy_ref_data(const struct dfs_info3_param *refs, int numrefs, 
	for (i = 0; i < numrefs; i++) {

		struct cache_dfs_tgt *t;



		t = alloc_target(refs[i].node_name);

		t = alloc_target(refs[i].node_name, refs[i].path_consumed);

		if (IS_ERR(t)) {

			free_tgts(ce);

			return PTR_ERR(t);
@@ -830,6 +832,7 @@ static int get_targets(struct cache_entry *ce, struct dfs_cache_tgt_list *tl) 
			rc = -ENOMEM;

			goto err_free_it;

		}

		it->it_path_consumed = t->path_consumed;



		if (ce->tgthint == t)

			list_add(&it->it_list, head);
@@ -1320,23 +1323,26 @@ void dfs_cache_del_vol(const char *fullpath) 
/**

 * dfs_cache_get_tgt_share - parse a DFS target

 *

 * @path: DFS full path

 * @it: DFS target iterator.

 * @share: tree name.

 * @share_len: length of tree name.

 * @prefix: prefix path.

 * @prefix_len: length of prefix path.

 *

 * Return zero if target was parsed correctly, otherwise non-zero.

 */

int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it,

			    const char **share, size_t *share_len,

			    const char **prefix, size_t *prefix_len)

int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it,

			    char **share, char **prefix)

{

	char *s, sep;

	char *s, sep, *p;

	size_t len;

	size_t plen1, plen2;



	if (!it || !share || !share_len || !prefix || !prefix_len)

	if (!it || !path || !share || !prefix || strlen(path) < it->it_path_consumed)

		return -EINVAL;



	*share = NULL;

	*prefix = NULL;



	sep = it->it_name[0];

	if (sep != '\\' && sep != '/')

		return -EINVAL;
@@ -1345,13 +1351,38 @@ int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it, 
	if (!s)

		return -EINVAL;



	/* point to prefix in target node */

	s = strchrnul(s + 1, sep);



	*share = it->it_name;

	*share_len = s - it->it_name;

	*prefix = *s ? s + 1 : s;

	*prefix_len = &it->it_name[strlen(it->it_name)] - *prefix;

	/* extract target share */

	*share = kstrndup(it->it_name, s - it->it_name, GFP_KERNEL);

	if (!*share)

		return -ENOMEM;



	/* skip separator */

	if (*s)

		s++;

	/* point to prefix in DFS path */

	p = path + it->it_path_consumed;

	if (*p == sep)

		p++;



	/* merge prefix paths from DFS path and target node */

	plen1 = it->it_name + strlen(it->it_name) - s;

	plen2 = path + strlen(path) - p;

	if (plen1 || plen2) {

		len = plen1 + plen2 + 2;

		*prefix = kmalloc(len, GFP_KERNEL);

		if (!*prefix) {

			kfree(*share);

			*share = NULL;

			return -ENOMEM;

		}

		if (plen1)

			scnprintf(*prefix, len, "%.*s%c%.*s", (int)plen1, s, sep, (int)plen2, p);

		else

			strscpy(*prefix, p, len);

	}

	return 0;

}

fs/cifs/dfs_cache.h

+3 −4
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ struct dfs_cache_tgt_list { 


struct dfs_cache_tgt_iterator {

	char *it_name;

	int it_path_consumed;

	struct list_head it_list;

};
@@ -48,10 +49,8 @@ extern int dfs_cache_add_vol(char *mntdata, struct smb_vol *vol, 
extern int dfs_cache_update_vol(const char *fullpath,

				struct TCP_Server_Info *server);

extern void dfs_cache_del_vol(const char *fullpath);



extern int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it,

				   const char **share, size_t *share_len,

				   const char **prefix, size_t *prefix_len);

extern int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it,

				   char **share, char **prefix);



static inline struct dfs_cache_tgt_iterator *

dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl,

fs/cifs/misc.c

+3 −4
Original line number Diff line number Diff line
@@ -1164,8 +1164,7 @@ static inline void cifs_put_tcon_super(struct super_block *sb) 
}

#endif



int update_super_prepath(struct cifs_tcon *tcon, const char *prefix,

			 size_t prefix_len)

int update_super_prepath(struct cifs_tcon *tcon, char *prefix)

{

	struct super_block *sb;

	struct cifs_sb_info *cifs_sb;
@@ -1179,8 +1178,8 @@ int update_super_prepath(struct cifs_tcon *tcon, const char *prefix, 


	kfree(cifs_sb->prepath);



	if (*prefix && prefix_len) {

		cifs_sb->prepath = kstrndup(prefix, prefix_len, GFP_ATOMIC);

	if (prefix && *prefix) {

		cifs_sb->prepath = kstrndup(prefix, strlen(prefix), GFP_ATOMIC);

		if (!cifs_sb->prepath) {

			rc = -ENOMEM;

			goto out;