From bf2afee14e07de16d3cafc67edbfc2a3cc65e4bc Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Fri, 8 Sep 2017 10:37:35 +1000 Subject: cifs: check rsp for NULL before dereferencing in SMB2_open In SMB2_open there are several paths where the SendReceive2 call will return an error before it sets rsp_iov.iov_base thus leaving iov_base uninitialized. Thus we need to check rsp before we dereference it in the call to get_rfc1002_length(). A report of this issue was previously reported in http://www.spinics.net/lists/linux-cifs/msg12846.html RH-bugzilla : 1476151 Version 2 : * Lets properly initialize rsp_iov before we use it. Signed-off-by: Ronnie Sahlberg Reviewed-by: Pavel Shilovsky . Signed-off-by: Steve French Reported-by: Xiaoli Feng CC: Stable --- fs/cifs/smb2pdu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 5531e7ee1210..69a751b038ab 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1634,7 +1634,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, struct cifs_tcon *tcon = oparms->tcon; struct cifs_ses *ses = tcon->ses; struct kvec iov[4]; - struct kvec rsp_iov; + struct kvec rsp_iov = {NULL, 0}; int resp_buftype; int uni_path_len; __le16 *copy_path = NULL; @@ -1763,7 +1763,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, if (rc != 0) { cifs_stats_fail_inc(tcon, SMB2_CREATE_HE); - if (err_buf) + if (err_buf && rsp) *err_buf = kmemdup(rsp, get_rfc1002_length(rsp) + 4, GFP_KERNEL); goto creat_exit; -- cgit v1.2.3 From 9764c02fcbad40001fd3f63558d918e4d519bb75 Mon Sep 17 00:00:00 2001 From: Steve French Date: Sun, 17 Sep 2017 10:41:35 -0500 Subject: SMB3: Add support for multidialect negotiate (SMB2.1 and later) With the need to discourage use of less secure dialect, SMB1 (CIFS), we temporarily upgraded the dialect to SMB3 in 4.13, but since there are various servers which only support SMB2.1 (2.1 is more secure than CIFS/SMB1) but not optimal for a default dialect - add support for multidialect negotiation. cifs.ko will now request SMB2.1 or later (ie SMB2.1 or SMB3.0, SMB3.02) and the server will pick the latest most secure one it can support. In addition since we are sending multidialect negotiate, add support for secure negotiate to validate that a man in the middle didn't downgrade us. Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky CC: Stable # 4.13+ --- fs/cifs/cifsglob.h | 6 ++++ fs/cifs/connect.c | 24 ++++++++++----- fs/cifs/smb2ops.c | 40 +++++++++++++++++++++++++ fs/cifs/smb2pdu.c | 85 +++++++++++++++++++++++++++++++++++++++++++++++------- fs/cifs/smb2pdu.h | 2 +- 5 files changed, 139 insertions(+), 18 deletions(-) (limited to 'fs') diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 808486c29f0d..de5b2e1fcce5 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -188,6 +188,8 @@ enum smb_version { #ifdef CONFIG_CIFS_SMB311 Smb_311, #endif /* SMB311 */ + Smb_3any, + Smb_default, Smb_version_err }; @@ -1701,6 +1703,10 @@ extern struct smb_version_values smb20_values; #define SMB21_VERSION_STRING "2.1" extern struct smb_version_operations smb21_operations; extern struct smb_version_values smb21_values; +#define SMBDEFAULT_VERSION_STRING "default" +extern struct smb_version_values smbdefault_values; +#define SMB3ANY_VERSION_STRING "3" +extern struct smb_version_values smb3any_values; #define SMB30_VERSION_STRING "3.0" extern struct smb_version_operations smb30_operations; extern struct smb_version_values smb30_values; diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 5aa2d278ca84..8d38b22afb2b 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -301,6 +301,8 @@ static const match_table_t cifs_smb_version_tokens = { { Smb_311, SMB311_VERSION_STRING }, { Smb_311, ALT_SMB311_VERSION_STRING }, #endif /* SMB311 */ + { Smb_3any, SMB3ANY_VERSION_STRING }, + { Smb_default, SMBDEFAULT_VERSION_STRING }, { Smb_version_err, NULL } }; @@ -1148,6 +1150,14 @@ cifs_parse_smb_version(char *value, struct smb_vol *vol) vol->vals = &smb311_values; break; #endif /* SMB311 */ + case Smb_3any: + vol->ops = &smb30_operations; /* currently identical with 3.0 */ + vol->vals = &smb3any_values; + break; + case Smb_default: + vol->ops = &smb30_operations; /* currently identical with 3.0 */ + vol->vals = &smbdefault_values; + break; default: cifs_dbg(VFS, "Unknown vers= option specified: %s\n", value); return 1; @@ -1274,9 +1284,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname, vol->actimeo = CIFS_DEF_ACTIMEO; - /* FIXME: add autonegotiation for SMB3 or later rather than just SMB3 */ - vol->ops = &smb30_operations; /* both secure and accepted widely */ - vol->vals = &smb30_values; + /* offer SMB2.1 and later (SMB3 etc). Secure and widely accepted */ + vol->ops = &smb30_operations; + vol->vals = &smbdefault_values; vol->echo_interval = SMB_ECHO_INTERVAL_DEFAULT; @@ -1988,11 +1998,10 @@ cifs_parse_mount_options(const char *mountdata, const char *devname, if (got_version == false) pr_warn("No dialect specified on mount. Default has changed to " - "a more secure dialect, SMB3 (vers=3.0), from CIFS " + "a more secure dialect, SMB2.1 or later (e.g. SMB3), from CIFS " "(SMB1). To use the less secure SMB1 dialect to access " - "old servers which do not support SMB3 specify vers=1.0" - " on mount. For somewhat newer servers such as Windows " - "7 try vers=2.1.\n"); + "old servers which do not support SMB3 (or SMB2.1) specify vers=1.0" + " on mount.\n"); kfree(mountdata_copy); return 0; @@ -2133,6 +2142,7 @@ static int match_server(struct TCP_Server_Info *server, struct smb_vol *vol) if (vol->nosharesock) return 0; + /* BB update this for smb3any and default case */ if ((server->vals != vol->vals) || (server->ops != vol->ops)) return 0; diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index fb2934b9b97c..405a9bf13aac 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3110,6 +3110,46 @@ struct smb_version_values smb21_values = { .create_lease_size = sizeof(struct create_lease), }; +struct smb_version_values smb3any_values = { + .version_string = SMB3ANY_VERSION_STRING, + .protocol_id = SMB302_PROT_ID, /* doesn't matter, send protocol array */ + .req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION, + .large_lock_type = 0, + .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK, + .shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK, + .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK, + .header_size = sizeof(struct smb2_hdr), + .max_header_size = MAX_SMB2_HDR_SIZE, + .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .lock_cmd = SMB2_LOCK, + .cap_unix = 0, + .cap_nt_find = SMB2_NT_FIND, + .cap_large_files = SMB2_LARGE_FILES, + .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED, + .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED, + .create_lease_size = sizeof(struct create_lease_v2), +}; + +struct smb_version_values smbdefault_values = { + .version_string = SMBDEFAULT_VERSION_STRING, + .protocol_id = SMB302_PROT_ID, /* doesn't matter, send protocol array */ + .req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION, + .large_lock_type = 0, + .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK, + .shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK, + .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK, + .header_size = sizeof(struct smb2_hdr), + .max_header_size = MAX_SMB2_HDR_SIZE, + .read_rsp_size = sizeof(struct smb2_read_rsp) - 1, + .lock_cmd = SMB2_LOCK, + .cap_unix = 0, + .cap_nt_find = SMB2_NT_FIND, + .cap_large_files = SMB2_LARGE_FILES, + .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED, + .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED, + .create_lease_size = sizeof(struct create_lease_v2), +}; + struct smb_version_values smb30_values = { .version_string = SMB30_VERSION_STRING, .protocol_id = SMB30_PROT_ID, diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 69a751b038ab..5c16591a128e 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -491,10 +491,25 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) req->hdr.sync_hdr.SessionId = 0; - req->Dialects[0] = cpu_to_le16(ses->server->vals->protocol_id); - - req->DialectCount = cpu_to_le16(1); /* One vers= at a time for now */ - inc_rfc1001_len(req, 2); + if (strcmp(ses->server->vals->version_string, + SMB3ANY_VERSION_STRING) == 0) { + req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID); + req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID); + req->DialectCount = cpu_to_le16(2); + inc_rfc1001_len(req, 4); + } else if (strcmp(ses->server->vals->version_string, + SMBDEFAULT_VERSION_STRING) == 0) { + req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID); + req->Dialects[1] = cpu_to_le16(SMB30_PROT_ID); + req->Dialects[2] = cpu_to_le16(SMB302_PROT_ID); + req->DialectCount = cpu_to_le16(3); + inc_rfc1001_len(req, 6); + } else { + /* otherwise send specific dialect */ + req->Dialects[0] = cpu_to_le16(ses->server->vals->protocol_id); + req->DialectCount = cpu_to_le16(1); + inc_rfc1001_len(req, 2); + } /* only one of SMB2 signing flags may be set in SMB2 request */ if (ses->sign) @@ -528,16 +543,42 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) */ if (rc == -EOPNOTSUPP) { cifs_dbg(VFS, "Dialect not supported by server. Consider " - "specifying vers=1.0 or vers=2.1 on mount for accessing" + "specifying vers=1.0 or vers=2.0 on mount for accessing" " older servers\n"); goto neg_exit; } else if (rc != 0) goto neg_exit; + if (strcmp(ses->server->vals->version_string, + SMB3ANY_VERSION_STRING) == 0) { + if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) { + cifs_dbg(VFS, + "SMB2 dialect returned but not requested\n"); + return -EIO; + } else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) { + cifs_dbg(VFS, + "SMB2.1 dialect returned but not requested\n"); + return -EIO; + } + } else if (strcmp(ses->server->vals->version_string, + SMBDEFAULT_VERSION_STRING) == 0) { + if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) { + cifs_dbg(VFS, + "SMB2 dialect returned but not requested\n"); + return -EIO; + } else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) { + /* ops set to 3.0 by default for default so update */ + ses->server->ops = &smb21_operations; + } + } else if (rsp->DialectRevision != ses->server->vals->protocol_id) { + /* if requested single dialect ensure returned dialect matched */ + cifs_dbg(VFS, "Illegal 0x%x dialect returned: not requested\n", + cpu_to_le16(rsp->DialectRevision)); + return -EIO; + } + cifs_dbg(FYI, "mode 0x%x\n", rsp->SecurityMode); - /* BB we may eventually want to match the negotiated vs. requested - dialect, even though we are only requesting one at a time */ if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) cifs_dbg(FYI, "negotiated smb2.0 dialect\n"); else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) @@ -558,6 +599,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) } server->dialect = le16_to_cpu(rsp->DialectRevision); + /* BB: add check that dialect was valid given dialect(s) we asked for */ + /* SMB2 only has an extended negflavor */ server->negflavor = CIFS_NEGFLAVOR_EXTENDED; /* set it to the maximum buffer size value we can send with 1 credit */ @@ -606,6 +649,7 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon) struct validate_negotiate_info_req vneg_inbuf; struct validate_negotiate_info_rsp *pneg_rsp; u32 rsplen; + u32 inbuflen; /* max of 4 dialects */ cifs_dbg(FYI, "validate negotiate\n"); @@ -634,9 +678,30 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon) else vneg_inbuf.SecurityMode = 0; - vneg_inbuf.DialectCount = cpu_to_le16(1); - vneg_inbuf.Dialects[0] = - cpu_to_le16(tcon->ses->server->vals->protocol_id); + + if (strcmp(tcon->ses->server->vals->version_string, + SMB3ANY_VERSION_STRING) == 0) { + vneg_inbuf.Dialects[0] = cpu_to_le16(SMB30_PROT_ID); + vneg_inbuf.Dialects[1] = cpu_to_le16(SMB302_PROT_ID); + vneg_inbuf.DialectCount = cpu_to_le16(2); + /* structure is big enough for 3 dialects, sending only 2 */ + inbuflen = sizeof(struct validate_negotiate_info_req) - 2; + } else if (strcmp(tcon->ses->server->vals->version_string, + SMBDEFAULT_VERSION_STRING) == 0) { + vneg_inbuf.Dialects[0] = cpu_to_le16(SMB21_PROT_ID); + vneg_inbuf.Dialects[1] = cpu_to_le16(SMB30_PROT_ID); + vneg_inbuf.Dialects[2] = cpu_to_le16(SMB302_PROT_ID); + vneg_inbuf.DialectCount = cpu_to_le16(3); + /* structure is big enough for 3 dialects */ + inbuflen = sizeof(struct validate_negotiate_info_req); + } else { + /* otherwise specific dialect was requested */ + vneg_inbuf.Dialects[0] = + cpu_to_le16(tcon->ses->server->vals->protocol_id); + vneg_inbuf.DialectCount = cpu_to_le16(1); + /* structure is big enough for 3 dialects, sending only 1 */ + inbuflen = sizeof(struct validate_negotiate_info_req) - 4; + } rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID, FSCTL_VALIDATE_NEGOTIATE_INFO, true /* is_fsctl */, diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 393ed5f4e1b6..6c9653a130c8 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -716,7 +716,7 @@ struct validate_negotiate_info_req { __u8 Guid[SMB2_CLIENT_GUID_SIZE]; __le16 SecurityMode; __le16 DialectCount; - __le16 Dialects[1]; /* dialect (someday maybe list) client asked for */ + __le16 Dialects[3]; /* BB expand this if autonegotiate > 3 dialects */ } __packed; struct validate_negotiate_info_rsp { -- cgit v1.2.3 From 1368f155a972eab037f81b5dea82afd544227552 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 5 Sep 2017 11:24:15 +0200 Subject: cifs: hide unused functions The newly added SMB2+ attribute support causes unused function warnings when CONFIG_CIFS_XATTR is disabled: fs/cifs/smb2ops.c:563:1: error: 'smb2_set_ea' defined but not used [-Werror=unused-function] smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon, fs/cifs/smb2ops.c:513:1: error: 'smb2_query_eas' defined but not used [-Werror=unused-function] smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon, This adds another #ifdef around the affected functions. Fixes: 5517554e4313 ("cifs: Add support for writing attributes on SMB2+") Fixes: 95907fea4fd8 ("cifs: Add support for reading attributes on SMB2+") Signed-off-by: Arnd Bergmann Acked-by: Geert Uytterhoeven Signed-off-by: Steve French --- fs/cifs/smb2ops.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs') diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 405a9bf13aac..0dafdbae1f8c 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -426,6 +426,7 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon, return rc; } +#ifdef CONFIG_CIFS_XATTR static ssize_t move_smb2_ea_to_cifs(char *dst, size_t dst_size, struct smb2_file_full_ea_info *src, size_t src_size, @@ -613,6 +614,7 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon, return rc; } +#endif static bool smb2_can_echo(struct TCP_Server_Info *server) -- cgit v1.2.3 From 94a9daeaece415ce37ccb413b49a580e68e3477b Mon Sep 17 00:00:00 2001 From: Steve French Date: Tue, 12 Sep 2017 18:13:11 -0500 Subject: Update version of cifs module Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky --- fs/cifs/cifsfs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index 30bf89b1fd9a..5a10e566f0e6 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -149,5 +149,5 @@ 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 "2.09" +#define CIFS_VERSION "2.10" #endif /* _CIFSFS_H */ -- cgit v1.2.3