diff options
| -rw-r--r-- | fs/cifs/cifsglob.h | 1 | ||||
| -rw-r--r-- | fs/cifs/cifsproto.h | 44 | ||||
| -rw-r--r-- | fs/cifs/connect.c | 114 | ||||
| -rw-r--r-- | fs/cifs/dfs.c | 62 | ||||
| -rw-r--r-- | fs/cifs/ioctl.c | 2 | ||||
| -rw-r--r-- | fs/cifs/smb2pdu.c | 4 |
6 files changed, 147 insertions, 80 deletions
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 9c5cd332ce14..414685c5d530 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -1756,7 +1756,6 @@ struct cifs_mount_ctx { struct TCP_Server_Info *server; struct cifs_ses *ses; struct cifs_tcon *tcon; - char *origin_fullpath, *leaf_fullpath; struct list_head dfs_ses_list; }; diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index e2eff66eefab..c1c704990b98 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -8,6 +8,7 @@ #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" @@ -572,7 +573,7 @@ extern int E_md4hash(const unsigned char *passwd, unsigned char *p16, 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); @@ -696,4 +697,45 @@ struct super_block *cifs_get_tcon_super(struct cifs_tcon *tcon); 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 */ diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 9a730efbce32..eeeed6fda13b 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -996,10 +996,8 @@ static void clean_demultiplex_info(struct TCP_Server_Info *server) */ } -#ifdef CONFIG_CIFS_DFS_UPCALL kfree(server->origin_fullpath); kfree(server->leaf_fullpath); -#endif kfree(server); length = atomic_dec_return(&tcpSesAllocCount); @@ -1387,23 +1385,8 @@ match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx) 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; @@ -1434,27 +1417,41 @@ static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context * (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; @@ -1485,7 +1482,7 @@ cifs_find_tcp_session(struct smb3_fs_context *ctx) * 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; } @@ -1869,7 +1866,7 @@ cifs_free_ipc(struct cifs_ses *ses) 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) { @@ -1879,23 +1876,22 @@ cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx) 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; @@ -2250,6 +2246,8 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx) */ 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); @@ -2266,12 +2264,15 @@ get_ses_fail: } /* 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; @@ -2294,7 +2295,7 @@ cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx) 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; } @@ -2670,9 +2671,11 @@ compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data) 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) && @@ -2680,6 +2683,10 @@ match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data) 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) @@ -2698,7 +2705,6 @@ cifs_match_super(struct super_block *sb, void *data) 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); @@ -2713,18 +2719,16 @@ cifs_match_super(struct super_block *sb, void *data) 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; } @@ -3469,8 +3473,6 @@ 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; } diff --git a/fs/cifs/dfs.c b/fs/cifs/dfs.c index da4e083b1ab4..a93dbca1411b 100644 --- a/fs/cifs/dfs.c +++ b/fs/cifs/dfs.c @@ -99,7 +99,7 @@ static int get_session(struct cifs_mount_ctx *mnt_ctx, const char *full_path) 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; @@ -127,7 +127,7 @@ static int get_dfs_conn(struct cifs_mount_ctx *mnt_ctx, const char *ref_path, co { 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); @@ -160,7 +160,7 @@ static int get_dfs_conn(struct cifs_mount_ctx *mnt_ctx, const char *ref_path, co 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; } @@ -277,15 +277,21 @@ out: 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 @@ -294,23 +300,41 @@ int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs) * 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 */ diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c index 6419ec47c2a8..cb3be58cd55e 100644 --- a/fs/cifs/ioctl.c +++ b/fs/cifs/ioctl.c @@ -239,7 +239,7 @@ static int cifs_dump_full_key(struct cifs_tcon *tcon, struct smb3_full_key_debug * section, we need to make sure it won't be released * so increment its refcount */ - ses->ses_count++; + cifs_smb_ses_inc_refcount(ses); found = true; goto search_end; } diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 3ce63f0cd9f5..8e7c15e2fd91 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -3801,7 +3801,7 @@ void smb2_reconnect_server(struct work_struct *work) if (ses->tcon_ipc && ses->tcon_ipc->need_reconnect) { list_add_tail(&ses->tcon_ipc->rlist, &tmp_list); tcon_selected = tcon_exist = true; - ses->ses_count++; + cifs_smb_ses_inc_refcount(ses); } /* * handle the case where channel needs to reconnect @@ -3812,7 +3812,7 @@ void smb2_reconnect_server(struct work_struct *work) if (!tcon_selected && cifs_chan_needs_reconnect(ses, server)) { list_add_tail(&ses->rlist, &tmp_ses_list); ses_exist = true; - ses->ses_count++; + cifs_smb_ses_inc_refcount(ses); } spin_unlock(&ses->chan_lock); } |