#ifndef _CIFSPROTO_H
#define _CIFSPROTO_H
#include <linux/nls.h>
+#include <linux/ctype.h>
#include "trace.h"
#ifdef CONFIG_CIFS_DFS_UPCALL
#include "dfs_cache.h"
extern struct TCP_Server_Info *
cifs_find_tcp_session(struct smb3_fs_context *ctx);
-extern void cifs_put_smb_ses(struct cifs_ses *ses);
+void __cifs_put_smb_ses(struct cifs_ses *ses);
extern struct cifs_ses *
cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx);
void cifs_put_tcon_super(struct super_block *sb);
int cifs_wait_for_server_reconnect(struct TCP_Server_Info *server, bool retry);
+/* Put references of @ses and @ses->dfs_root_ses */
+static inline void cifs_put_smb_ses(struct cifs_ses *ses)
+{
+ struct cifs_ses *rses = ses->dfs_root_ses;
+
+ __cifs_put_smb_ses(ses);
+ if (rses)
+ __cifs_put_smb_ses(rses);
+}
+
+/* Get an active reference of @ses and @ses->dfs_root_ses.
+ *
+ * NOTE: make sure to call this function when incrementing reference count of
+ * @ses to ensure that any DFS root session attached to it (@ses->dfs_root_ses)
+ * will also get its reference count incremented.
+ *
+ * cifs_put_smb_ses() will put both references, so call it when you're done.
+ */
+static inline void cifs_smb_ses_inc_refcount(struct cifs_ses *ses)
+{
+ lockdep_assert_held(&cifs_tcp_ses_lock);
+
+ ses->ses_count++;
+ if (ses->dfs_root_ses)
+ ses->dfs_root_ses->ses_count++;
+}
+
+static inline bool dfs_src_pathname_equal(const char *s1, const char *s2)
+{
+ if (strlen(s1) != strlen(s2))
+ return false;
+ for (; *s1; s1++, s2++) {
+ if (*s1 == '/' || *s1 == '\\') {
+ if (*s2 != '/' && *s2 != '\\')
+ return false;
+ } else if (tolower(*s1) != tolower(*s2))
+ return false;
+ }
+ return true;
+}
+
#endif /* _CIFSPROTO_H */
*/
}
-#ifdef CONFIG_CIFS_DFS_UPCALL
kfree(server->origin_fullpath);
kfree(server->leaf_fullpath);
-#endif
kfree(server);
length = atomic_dec_return(&tcpSesAllocCount);
return true;
}
-static bool dfs_src_pathname_equal(const char *s1, const char *s2)
-{
- if (strlen(s1) != strlen(s2))
- return false;
- for (; *s1; s1++, s2++) {
- if (*s1 == '/' || *s1 == '\\') {
- if (*s2 != '/' && *s2 != '\\')
- return false;
- } else if (tolower(*s1) != tolower(*s2))
- return false;
- }
- return true;
-}
-
/* this function must be called with srv_lock held */
-static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context *ctx,
- bool dfs_super_cmp)
+static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
(struct sockaddr *)&server->srcaddr))
return 0;
/*
- * When matching DFS superblocks, we only check for original source pathname as the
- * currently connected target might be different than the one parsed earlier in i.e.
- * mount.cifs(8).
+ * - Match for an DFS tcon (@server->origin_fullpath).
+ * - Match for an DFS root server connection (@server->leaf_fullpath).
+ * - If none of the above and @ctx->leaf_fullpath is set, then
+ * it is a new DFS connection.
+ * - If 'nodfs' mount option was passed, then match only connections
+ * that have no DFS referrals set
+ * (e.g. can't failover to other targets).
*/
- if (dfs_super_cmp) {
- if (!ctx->source || !server->origin_fullpath ||
- !dfs_src_pathname_equal(server->origin_fullpath, ctx->source))
- return 0;
- } else {
- /* Skip addr, hostname and port matching for DFS connections */
- if (server->leaf_fullpath) {
+ if (!ctx->nodfs) {
+ if (ctx->source && server->origin_fullpath) {
+ if (!dfs_src_pathname_equal(ctx->source,
+ server->origin_fullpath))
+ return 0;
+ } else if (server->leaf_fullpath) {
if (!ctx->leaf_fullpath ||
- strcasecmp(server->leaf_fullpath, ctx->leaf_fullpath))
+ strcasecmp(server->leaf_fullpath,
+ ctx->leaf_fullpath))
return 0;
- } else if (strcasecmp(server->hostname, ctx->server_hostname) ||
- !match_server_address(server, addr) ||
- !match_port(server, addr)) {
+ } else if (ctx->leaf_fullpath) {
return 0;
}
+ } else if (server->origin_fullpath || server->leaf_fullpath) {
+ return 0;
}
+ /*
+ * Match for a regular connection (address/hostname/port) which has no
+ * DFS referrals set.
+ */
+ if (!server->origin_fullpath && !server->leaf_fullpath &&
+ (strcasecmp(server->hostname, ctx->server_hostname) ||
+ !match_server_address(server, addr) ||
+ !match_port(server, addr)))
+ return 0;
+
if (!match_security(server, ctx))
return 0;
* Skip ses channels since they're only handled in lower layers
* (e.g. cifs_send_recv).
*/
- if (CIFS_SERVER_IS_CHAN(server) || !match_server(server, ctx, false)) {
+ if (CIFS_SERVER_IS_CHAN(server) || !match_server(server, ctx)) {
spin_unlock(&server->srv_lock);
continue;
}
static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
- struct cifs_ses *ses;
+ struct cifs_ses *ses, *ret = NULL;
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
continue;
}
spin_lock(&ses->chan_lock);
- if (!match_session(ses, ctx)) {
+ if (match_session(ses, ctx)) {
spin_unlock(&ses->chan_lock);
spin_unlock(&ses->ses_lock);
- continue;
+ ret = ses;
+ break;
}
spin_unlock(&ses->chan_lock);
spin_unlock(&ses->ses_lock);
-
- ++ses->ses_count;
- spin_unlock(&cifs_tcp_ses_lock);
- return ses;
}
+ if (ret)
+ cifs_smb_ses_inc_refcount(ret);
spin_unlock(&cifs_tcp_ses_lock);
- return NULL;
+ return ret;
}
-void cifs_put_smb_ses(struct cifs_ses *ses)
+void __cifs_put_smb_ses(struct cifs_ses *ses)
{
unsigned int rc, xid;
unsigned int chan_count;
*/
spin_lock(&cifs_tcp_ses_lock);
ses->dfs_root_ses = ctx->dfs_root_ses;
+ if (ses->dfs_root_ses)
+ ses->dfs_root_ses->ses_count++;
list_add(&ses->smb_ses_list, &server->smb_ses_list);
spin_unlock(&cifs_tcp_ses_lock);
}
/* this function must be called with tc_lock held */
-static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx, bool dfs_super_cmp)
+static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
+ struct TCP_Server_Info *server = tcon->ses->server;
+
if (tcon->status == TID_EXITING)
return 0;
- /* Skip UNC validation when matching DFS superblocks */
- if (!dfs_super_cmp && strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE))
+ /* Skip UNC validation when matching DFS connections or superblocks */
+ if (!server->origin_fullpath && !server->leaf_fullpath &&
+ strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE))
return 0;
if (tcon->seal != ctx->seal)
return 0;
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
spin_lock(&tcon->tc_lock);
- if (!match_tcon(tcon, ctx, false)) {
+ if (!match_tcon(tcon, ctx)) {
spin_unlock(&tcon->tc_lock);
continue;
}
return 1;
}
-static int
-match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
+static int match_prepath(struct super_block *sb,
+ struct TCP_Server_Info *server,
+ struct cifs_mnt_data *mnt_data)
{
+ struct smb3_fs_context *ctx = mnt_data->ctx;
struct cifs_sb_info *old = CIFS_SB(sb);
struct cifs_sb_info *new = mnt_data->cifs_sb;
bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
new->prepath;
+ if (server->origin_fullpath &&
+ dfs_src_pathname_equal(server->origin_fullpath, ctx->source))
+ return 1;
+
if (old_set && new_set && !strcmp(new->prepath, old->prepath))
return 1;
else if (!old_set && !new_set)
struct cifs_ses *ses;
struct cifs_tcon *tcon;
struct tcon_link *tlink;
- bool dfs_super_cmp;
int rc = 0;
spin_lock(&cifs_tcp_ses_lock);
ses = tcon->ses;
tcp_srv = ses->server;
- dfs_super_cmp = IS_ENABLED(CONFIG_CIFS_DFS_UPCALL) && tcp_srv->origin_fullpath;
-
ctx = mnt_data->ctx;
spin_lock(&tcp_srv->srv_lock);
spin_lock(&ses->ses_lock);
spin_lock(&ses->chan_lock);
spin_lock(&tcon->tc_lock);
- if (!match_server(tcp_srv, ctx, dfs_super_cmp) ||
+ if (!match_server(tcp_srv, ctx) ||
!match_session(ses, ctx) ||
- !match_tcon(tcon, ctx, dfs_super_cmp) ||
- !match_prepath(sb, mnt_data)) {
+ !match_tcon(tcon, ctx) ||
+ !match_prepath(sb, tcp_srv, mnt_data)) {
rc = 0;
goto out;
}
error:
dfs_put_root_smb_sessions(&mnt_ctx.dfs_ses_list);
- kfree(mnt_ctx.origin_fullpath);
- kfree(mnt_ctx.leaf_fullpath);
cifs_mount_put_conns(&mnt_ctx);
return rc;
}
return rc;
}
-static int get_root_smb_session(struct cifs_mount_ctx *mnt_ctx)
+static int add_root_smb_session(struct cifs_mount_ctx *mnt_ctx)
{
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
struct dfs_root_ses *root_ses;
{
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
struct dfs_info3_param ref = {};
- bool is_refsrv = false;
+ bool is_refsrv;
int rc, rc2;
rc = dfs_cache_get_tgt_referral(ref_path + 1, tit, &ref);
dfs_cache_noreq_update_tgthint(ref_path + 1, tit);
if (rc == -EREMOTE && is_refsrv) {
- rc2 = get_root_smb_session(mnt_ctx);
+ rc2 = add_root_smb_session(mnt_ctx);
if (rc2)
rc = rc2;
}
int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs)
{
- struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+ struct cifs_ses *ses;
+ char *source = ctx->source;
+ bool nodfs = ctx->nodfs;
int rc;
*isdfs = false;
-
+ /* Temporarily set @ctx->source to NULL as we're not matching DFS
+ * superblocks yet. See cifs_match_super() and match_server().
+ */
+ ctx->source = NULL;
rc = get_session(mnt_ctx, NULL);
if (rc)
- return rc;
+ goto out;
+
ctx->dfs_root_ses = mnt_ctx->ses;
/*
* If called with 'nodfs' mount option, then skip DFS resolving. Otherwise unconditionally
* Skip prefix path to provide support for DFS referrals from w2k8 servers which don't seem
* to respond with PATH_NOT_COVERED to requests that include the prefix.
*/
- if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) ||
- dfs_get_referral(mnt_ctx, ctx->UNC + 1, NULL, NULL)) {
+ if (!nodfs) {
+ rc = dfs_get_referral(mnt_ctx, ctx->UNC + 1, NULL, NULL);
+ if (rc) {
+ if (rc != -ENOENT && rc != -EOPNOTSUPP)
+ goto out;
+ nodfs = true;
+ }
+ }
+ if (nodfs) {
rc = cifs_mount_get_tcon(mnt_ctx);
- if (rc)
- return rc;
-
- rc = cifs_is_path_remote(mnt_ctx);
- if (!rc || rc != -EREMOTE)
- return rc;
+ if (!rc)
+ rc = cifs_is_path_remote(mnt_ctx);
+ goto out;
}
*isdfs = true;
- rc = get_root_smb_session(mnt_ctx);
- if (rc)
- return rc;
-
- return __dfs_mount_share(mnt_ctx);
+ /*
+ * Prevent DFS root session of being put in the first call to
+ * cifs_mount_put_conns(). If another DFS root server was not found
+ * while chasing the referrals (@ctx->dfs_root_ses == @ses), then we
+ * can safely put extra refcount of @ses.
+ */
+ ses = mnt_ctx->ses;
+ mnt_ctx->ses = NULL;
+ mnt_ctx->server = NULL;
+ rc = __dfs_mount_share(mnt_ctx);
+ if (ses == ctx->dfs_root_ses)
+ cifs_put_smb_ses(ses);
+out:
+ /*
+ * Restore previous value of @ctx->source so DFS superblock can be
+ * matched in cifs_match_super().
+ */
+ ctx->source = source;
+ return rc;
}
/* Update dfs referral path of superblock */
projects / linux.git / commitdiff