From 7e5a70ad88b1e6f6d9b934b2efb41afff496820f Mon Sep 17 00:00:00 2001 From: Aurelien Aptel Date: Wed, 17 Jul 2019 12:46:28 +0200 Subject: [PATCH 1/5] CIFS: fix deadlock in cached root handling Prevent deadlock between open_shroot() and cifs_mark_open_files_invalid() by releasing the lock before entering SMB2_open, taking it again after and checking if we still need to use the result. Link: https://lore.kernel.org/linux-cifs/684ed01c-cbca-2716-bc28-b0a59a0f8521@prodrive-technologies.com/T/#u Fixes: 3d4ef9a15343 ("smb3: fix redundant opens on root") Signed-off-by: Aurelien Aptel Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French CC: Stable --- fs/cifs/smb2ops.c | 46 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 45 insertions(+), 1 deletion(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 0cdc4e47ca87..fed75e1646c1 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -694,8 +694,51 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid) smb2_set_related(&rqst[1]); + /* + * We do not hold the lock for the open because in case + * SMB2_open needs to reconnect, it will end up calling + * cifs_mark_open_files_invalid() which takes the lock again + * thus causing a deadlock + */ + + mutex_unlock(&tcon->crfid.fid_mutex); rc = compound_send_recv(xid, ses, flags, 2, rqst, resp_buftype, rsp_iov); + mutex_lock(&tcon->crfid.fid_mutex); + + /* + * Now we need to check again as the cached root might have + * been successfully re-opened from a concurrent process + */ + + if (tcon->crfid.is_valid) { + /* work was already done */ + + /* stash fids for close() later */ + struct cifs_fid fid = { + .persistent_fid = pfid->persistent_fid, + .volatile_fid = pfid->volatile_fid, + }; + + /* + * caller expects this func to set pfid to a valid + * cached root, so we copy the existing one and get a + * reference. + */ + memcpy(pfid, tcon->crfid.fid, sizeof(*pfid)); + kref_get(&tcon->crfid.refcount); + + mutex_unlock(&tcon->crfid.fid_mutex); + + if (rc == 0) { + /* close extra handle outside of crit sec */ + SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); + } + goto oshr_free; + } + + /* Cached root is still invalid, continue normaly */ + if (rc) goto oshr_exit; @@ -729,8 +772,9 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid) (char *)&tcon->crfid.file_all_info)) tcon->crfid.file_all_info_is_valid = 1; - oshr_exit: +oshr_exit: mutex_unlock(&tcon->crfid.fid_mutex); +oshr_free: SMB2_open_free(&rqst[0]); SMB2_query_info_free(&rqst[1]); free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base); From bf3c90ee1efe4dd3417d2129f9f6c68a4c76de00 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Mon, 10 Jun 2019 20:36:57 +0300 Subject: [PATCH 2/5] cifs: copy_file_range needs to strip setuid bits and update timestamps cifs has both source and destination inodes locked throughout the copy. Like ->write_iter(), we update mtime and strip setuid bits of destination file before copy and like ->read_iter(), we update atime of source file after copy. Signed-off-by: Amir Goldstein Signed-off-by: Steve French --- fs/cifs/cifsfs.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 270d3c58fb3b..3289b566463f 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -1104,6 +1104,10 @@ ssize_t cifs_file_copychunk_range(unsigned int xid, goto out; } + rc = -EOPNOTSUPP; + if (!target_tcon->ses->server->ops->copychunk_range) + goto out; + /* * Note: cifs case is easier than btrfs since server responsible for * checks for proper open modes and file type and if it wants @@ -1115,11 +1119,12 @@ ssize_t cifs_file_copychunk_range(unsigned int xid, /* should we flush first and last page first */ truncate_inode_pages(&target_inode->i_data, 0); - if (target_tcon->ses->server->ops->copychunk_range) + rc = file_modified(dst_file); + if (!rc) rc = target_tcon->ses->server->ops->copychunk_range(xid, smb_file_src, smb_file_target, off, len, destoff); - else - rc = -EOPNOTSUPP; + + file_accessed(src_file); /* force revalidate of size and timestamps of target file now * that target is updated on the server From 89a5bfa350faf87156acda4d7c457808bfecaa0e Mon Sep 17 00:00:00 2001 From: Steve French Date: Thu, 18 Jul 2019 17:22:18 -0500 Subject: [PATCH 3/5] smb3: optimize open to not send query file internal info We can cut one third of the traffic on open by not querying the inode number explicitly via SMB3 query_info since it is now returned on open in the qfid context. This is better in multiple ways, and speeds up file open about 10% (more if network is slow). Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/smb2file.c | 18 ++++++++++++------ fs/cifs/smb2ops.c | 7 ++++--- fs/cifs/smb2pdu.c | 46 ++++++++++++++++++++++++++++++++------------- fs/cifs/smb2pdu.h | 4 +++- fs/cifs/smb2proto.h | 7 ++++--- 5 files changed, 56 insertions(+), 26 deletions(-) diff --git a/fs/cifs/smb2file.c b/fs/cifs/smb2file.c index 54bffb2a1786..e6a1fc72018f 100644 --- a/fs/cifs/smb2file.c +++ b/fs/cifs/smb2file.c @@ -88,14 +88,20 @@ smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms, } if (buf) { - /* open response does not have IndexNumber field - get it */ - rc = SMB2_get_srv_num(xid, oparms->tcon, fid->persistent_fid, + /* if open response does not have IndexNumber field - get it */ + if (smb2_data->IndexNumber == 0) { + rc = SMB2_get_srv_num(xid, oparms->tcon, + fid->persistent_fid, fid->volatile_fid, &smb2_data->IndexNumber); - if (rc) { - /* let get_inode_info disable server inode numbers */ - smb2_data->IndexNumber = 0; - rc = 0; + if (rc) { + /* + * let get_inode_info disable server inode + * numbers + */ + smb2_data->IndexNumber = 0; + rc = 0; + } } move_smb2_info_to_cifs(buf, smb2_data); } diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index fed75e1646c1..a5bc1b671c12 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -754,11 +754,12 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid) tcon->crfid.is_valid = true; kref_init(&tcon->crfid.refcount); + /* BB TBD check to see if oplock level check can be removed below */ if (o_rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE) { kref_get(&tcon->crfid.refcount); - oplock = smb2_parse_lease_state(server, o_rsp, - &oparms.fid->epoch, - oparms.fid->lease_key); + smb2_parse_contexts(server, o_rsp, + &oparms.fid->epoch, + oparms.fid->lease_key, &oplock, NULL); } else goto oshr_exit; diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index f58e4dc3987b..c8cd7b6cdda2 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1873,10 +1873,21 @@ create_reconnect_durable_buf(struct cifs_fid *fid) return buf; } -__u8 -smb2_parse_lease_state(struct TCP_Server_Info *server, +static void +parse_query_id_ctxt(struct create_context *cc, struct smb2_file_all_info *buf) +{ + struct create_on_disk_id *pdisk_id = (struct create_on_disk_id *)cc; + + cifs_dbg(FYI, "parse query id context 0x%llx 0x%llx\n", + pdisk_id->DiskFileId, pdisk_id->VolumeId); + buf->IndexNumber = pdisk_id->DiskFileId; +} + +void +smb2_parse_contexts(struct TCP_Server_Info *server, struct smb2_create_rsp *rsp, - unsigned int *epoch, char *lease_key) + unsigned int *epoch, char *lease_key, __u8 *oplock, + struct smb2_file_all_info *buf) { char *data_offset; struct create_context *cc; @@ -1884,15 +1895,24 @@ smb2_parse_lease_state(struct TCP_Server_Info *server, unsigned int remaining; char *name; + *oplock = 0; data_offset = (char *)rsp + le32_to_cpu(rsp->CreateContextsOffset); remaining = le32_to_cpu(rsp->CreateContextsLength); cc = (struct create_context *)data_offset; + + /* Initialize inode number to 0 in case no valid data in qfid context */ + if (buf) + buf->IndexNumber = 0; + while (remaining >= sizeof(struct create_context)) { name = le16_to_cpu(cc->NameOffset) + (char *)cc; if (le16_to_cpu(cc->NameLength) == 4 && - strncmp(name, "RqLs", 4) == 0) - return server->ops->parse_lease_buf(cc, epoch, - lease_key); + strncmp(name, SMB2_CREATE_REQUEST_LEASE, 4) == 0) + *oplock = server->ops->parse_lease_buf(cc, epoch, + lease_key); + else if (buf && (le16_to_cpu(cc->NameLength) == 4) && + strncmp(name, SMB2_CREATE_QUERY_ON_DISK_ID, 4) == 0) + parse_query_id_ctxt(cc, buf); next = le32_to_cpu(cc->Next); if (!next) @@ -1901,7 +1921,10 @@ smb2_parse_lease_state(struct TCP_Server_Info *server, cc = (struct create_context *)((char *)cc + next); } - return 0; + if (rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE) + *oplock = rsp->OplockLevel; + + return; } static int @@ -2588,12 +2611,9 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, buf->DeletePending = 0; } - if (rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE) - *oplock = smb2_parse_lease_state(server, rsp, - &oparms->fid->epoch, - oparms->fid->lease_key); - else - *oplock = rsp->OplockLevel; + + smb2_parse_contexts(server, rsp, &oparms->fid->epoch, + oparms->fid->lease_key, oplock, buf); creat_exit: SMB2_open_free(&rqst); free_rsp_buf(resp_buftype, rsp); diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 7e2e782f8edd..747de9317659 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -818,7 +818,9 @@ struct durable_reconnect_context_v2 { } __packed; /* See MS-SMB2 2.2.14.2.9 */ -struct on_disk_id { +struct create_on_disk_id { + struct create_context ccontext; + __u8 Name[8]; __le64 DiskFileId; __le64 VolumeId; __u32 Reserved[4]; diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h index 52df125e9189..07ca72486cfa 100644 --- a/fs/cifs/smb2proto.h +++ b/fs/cifs/smb2proto.h @@ -228,9 +228,10 @@ extern int smb3_validate_negotiate(const unsigned int, struct cifs_tcon *); extern enum securityEnum smb2_select_sectype(struct TCP_Server_Info *, enum securityEnum); -extern __u8 smb2_parse_lease_state(struct TCP_Server_Info *server, - struct smb2_create_rsp *rsp, - unsigned int *epoch, char *lease_key); +extern void smb2_parse_contexts(struct TCP_Server_Info *server, + struct smb2_create_rsp *rsp, + unsigned int *epoch, char *lease_key, + __u8 *oplock, struct smb2_file_all_info *buf); extern int smb3_encryption_required(const struct cifs_tcon *tcon); extern int smb2_validate_iov(unsigned int offset, unsigned int buffer_length, struct kvec *iov, unsigned int min_buf_size); From aa081859b10c5d8b19f5c525c78883a59d73c2b8 Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Fri, 19 Jul 2019 08:12:11 +1000 Subject: [PATCH 4/5] cifs: flush before set-info if we have writeable handles Servers can defer destaging any data and updating the mtime until close(). This means that if we do a setinfo to modify the mtime while other handles are open for write the server may overwrite our setinfo timestamps when if flushes the file on close() of the writeable handle. To solve this we add an explicit flush when the mtime is about to be updated. This fixes "cp -p" to preserve mtime when copying a file onto an SMB2 share. CC: Stable Signed-off-by: Ronnie Sahlberg Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/inode.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index 1bffe029fb66..56ca4b8ccaba 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -2406,6 +2406,8 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs) struct inode *inode = d_inode(direntry); struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); struct cifsInodeInfo *cifsInode = CIFS_I(inode); + struct cifsFileInfo *wfile; + struct cifs_tcon *tcon; char *full_path = NULL; int rc = -EACCES; __u32 dosattr = 0; @@ -2452,6 +2454,20 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs) mapping_set_error(inode->i_mapping, rc); rc = 0; + if (attrs->ia_valid & ATTR_MTIME) { + rc = cifs_get_writable_file(cifsInode, false, &wfile); + if (!rc) { + tcon = tlink_tcon(wfile->tlink); + rc = tcon->ses->server->ops->flush(xid, tcon, &wfile->fid); + cifsFileInfo_put(wfile); + if (rc) + return rc; + } else if (rc != -EBADF) + return rc; + else + rc = 0; + } + if (attrs->ia_valid & ATTR_SIZE) { rc = cifs_set_file_size(inode, attrs, xid, full_path); if (rc != 0) From 2a957ace44d4cf0f6194a4209d4fa67ee5461d8f Mon Sep 17 00:00:00 2001 From: Steve French Date: Mon, 1 Jul 2019 16:25:46 -0500 Subject: [PATCH 5/5] cifs: update internal module number To 2.21 Signed-off-by: Steve French --- fs/cifs/cifsfs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index aea005703785..4b21a90015a9 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -152,5 +152,5 @@ extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg); extern const struct export_operations cifs_export_ops; #endif /* CONFIG_CIFS_NFSD_EXPORT */ -#define CIFS_VERSION "2.20" +#define CIFS_VERSION "2.21" #endif /* _CIFSFS_H */