diff options
Diffstat (limited to 'fs/cifs/dfs_cache.c')
-rw-r--r-- | fs/cifs/dfs_cache.c | 136 |
1 files changed, 112 insertions, 24 deletions
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c index 7a8d41493aad..6ee849698962 100644 --- a/fs/cifs/dfs_cache.c +++ b/fs/cifs/dfs_cache.c @@ -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); @@ -490,16 +492,7 @@ static int add_cache_entry(const char *path, unsigned int hash, return 0; } -/* - * Find a DFS cache entry in hash table and optionally check prefix path against - * @path. - * Use whole path components in the match. - * Must be called with htable_rw_lock held. - * - * Return ERR_PTR(-ENOENT) if the entry is not found. - */ -static struct cache_entry *lookup_cache_entry(const char *path, - unsigned int *hash) +static struct cache_entry *__lookup_cache_entry(const char *path) { struct cache_entry *ce; unsigned int h; @@ -517,9 +510,75 @@ static struct cache_entry *lookup_cache_entry(const char *path, if (!found) ce = ERR_PTR(-ENOENT); + return ce; +} + +/* + * Find a DFS cache entry in hash table and optionally check prefix path against + * @path. + * Use whole path components in the match. + * Must be called with htable_rw_lock held. + * + * Return ERR_PTR(-ENOENT) if the entry is not found. + */ +static struct cache_entry *lookup_cache_entry(const char *path, unsigned int *hash) +{ + struct cache_entry *ce = ERR_PTR(-ENOENT); + unsigned int h; + int cnt = 0; + char *npath; + char *s, *e; + char sep; + + npath = kstrndup(path, strlen(path), GFP_KERNEL); + if (!npath) + return ERR_PTR(-ENOMEM); + + s = npath; + sep = *npath; + while ((s = strchr(s, sep)) && ++cnt < 3) + s++; + + if (cnt < 3) { + h = cache_entry_hash(path, strlen(path)); + ce = __lookup_cache_entry(path); + goto out; + } + /* + * Handle paths that have more than two path components and are a complete prefix of the DFS + * referral request path (@path). + * + * See MS-DFSC 3.2.5.5 "Receiving a Root Referral Request or Link Referral Request". + */ + h = cache_entry_hash(npath, strlen(npath)); + e = npath + strlen(npath) - 1; + while (e > s) { + char tmp; + + /* skip separators */ + while (e > s && *e == sep) + e--; + if (e == s) + goto out; + + tmp = *(e+1); + *(e+1) = 0; + + ce = __lookup_cache_entry(npath); + if (!IS_ERR(ce)) { + h = cache_entry_hash(npath, strlen(npath)); + break; + } + + *(e+1) = tmp; + /* backward until separator */ + while (e > s && *e != sep) + e--; + } +out: if (hash) *hash = h; - + kfree(npath); return ce; } @@ -773,6 +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); @@ -1263,23 +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; @@ -1288,13 +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; } |