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Diffstat (limited to 'fs/smb/client/dfs.c')
-rw-r--r--fs/smb/client/dfs.c51
1 files changed, 24 insertions, 27 deletions
diff --git a/fs/smb/client/dfs.c b/fs/smb/client/dfs.c
index 449c598300..3ec965547e 100644
--- a/fs/smb/client/dfs.c
+++ b/fs/smb/client/dfs.c
@@ -66,33 +66,20 @@ static int get_session(struct cifs_mount_ctx *mnt_ctx, const char *full_path)
}
/*
- * Track individual DFS referral servers used by new DFS mount.
- *
- * On success, their lifetime will be shared by final tcon (dfs_ses_list).
- * Otherwise, they will be put by dfs_put_root_smb_sessions() in cifs_mount().
+ * Get an active reference of @ses so that next call to cifs_put_tcon() won't
+ * release it as any new DFS referrals must go through its IPC tcon.
*/
-static int add_root_smb_session(struct cifs_mount_ctx *mnt_ctx)
+static void 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 cifs_ses *ses = mnt_ctx->ses;
if (ses) {
- root_ses = kmalloc(sizeof(*root_ses), GFP_KERNEL);
- if (!root_ses)
- return -ENOMEM;
-
- INIT_LIST_HEAD(&root_ses->list);
-
spin_lock(&cifs_tcp_ses_lock);
cifs_smb_ses_inc_refcount(ses);
spin_unlock(&cifs_tcp_ses_lock);
- root_ses->ses = ses;
- list_add_tail(&root_ses->list, &mnt_ctx->dfs_ses_list);
}
- /* Select new DFS referral server so that new referrals go through it */
ctx->dfs_root_ses = ses;
- return 0;
}
static inline int parse_dfs_target(struct smb3_fs_context *ctx,
@@ -185,11 +172,8 @@ again:
continue;
}
- if (is_refsrv) {
- rc = add_root_smb_session(mnt_ctx);
- if (rc)
- goto out;
- }
+ if (is_refsrv)
+ add_root_smb_session(mnt_ctx);
rc = ref_walk_advance(rw);
if (!rc) {
@@ -232,6 +216,7 @@ static int __dfs_mount_share(struct cifs_mount_ctx *mnt_ctx)
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
struct cifs_tcon *tcon;
char *origin_fullpath;
+ bool new_tcon = true;
int rc;
origin_fullpath = dfs_get_path(cifs_sb, ctx->source);
@@ -239,6 +224,18 @@ static int __dfs_mount_share(struct cifs_mount_ctx *mnt_ctx)
return PTR_ERR(origin_fullpath);
rc = dfs_referral_walk(mnt_ctx);
+ if (!rc) {
+ /*
+ * Prevent superblock from being created with any missing
+ * connections.
+ */
+ if (WARN_ON(!mnt_ctx->server))
+ rc = -EHOSTDOWN;
+ else if (WARN_ON(!mnt_ctx->ses))
+ rc = -EACCES;
+ else if (WARN_ON(!mnt_ctx->tcon))
+ rc = -ENOENT;
+ }
if (rc)
goto out;
@@ -247,15 +244,14 @@ static int __dfs_mount_share(struct cifs_mount_ctx *mnt_ctx)
if (!tcon->origin_fullpath) {
tcon->origin_fullpath = origin_fullpath;
origin_fullpath = NULL;
+ } else {
+ new_tcon = false;
}
spin_unlock(&tcon->tc_lock);
- if (list_empty(&tcon->dfs_ses_list)) {
- list_replace_init(&mnt_ctx->dfs_ses_list, &tcon->dfs_ses_list);
+ if (new_tcon) {
queue_delayed_work(dfscache_wq, &tcon->dfs_cache_work,
dfs_cache_get_ttl() * HZ);
- } else {
- dfs_put_root_smb_sessions(&mnt_ctx->dfs_ses_list);
}
out:
@@ -298,7 +294,6 @@ int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs)
if (rc)
return rc;
- ctx->dfs_root_ses = mnt_ctx->ses;
/*
* If called with 'nodfs' mount option, then skip DFS resolving. Otherwise unconditionally
* try to get an DFS referral (even cached) to determine whether it is an DFS mount.
@@ -324,7 +319,9 @@ int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs)
*isdfs = true;
add_root_smb_session(mnt_ctx);
- return __dfs_mount_share(mnt_ctx);
+ rc = __dfs_mount_share(mnt_ctx);
+ dfs_put_root_smb_sessions(mnt_ctx);
+ return rc;
}
/* Update dfs referral path of superblock */