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2025-06-02cifs: update dstaddr whenever channel iface is updatedShyam Prasad N
When the server interface info changes (more common in clustered servers like Azure Files), the per-channel iface gets updated. However, this did not update the corresponding dstaddr. As a result these channels will still connect (or try connecting) to older addresses. Fixes: b54034a73baf ("cifs: during reconnect, update interface if necessary") Cc: <stable@vger.kernel.org> Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-02cifs: reset connections for all channels when reconnect requestedShyam Prasad N
cifs_reconnect can be called with a flag to mark the session as needing reconnect too. When this is done, we expect the connections of all channels to be reconnected too, which is not happening today. Without doing this, we have seen bad things happen when primary and secondary channels are connected to different servers (in case of cloud services like Azure Files SMB). This change would force all connections to reconnect as well, not just the sessions and tcons. Cc: <stable@vger.kernel.org> Signed-off-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01smb: client: use ParentLeaseKey in cifs_do_createHenrique Carvalho
Implement ParentLeaseKey logic in cifs_do_create() by looking up the parent cfid, copying its lease key into the fid struct, and setting the appropriate lease flag. Fixes: f047390a097e ("CIFS: Add create lease v2 context for SMB3") Signed-off-by: Henrique Carvalho <henrique.carvalho@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01smb: client: use ParentLeaseKey in open_cached_dirHenrique Carvalho
Implement ParentLeaseKey logic in open_cached_dir() by looking up the parent cfid, copying its lease key into the fid struct, and setting the appropriate lease flag. Fixes: f047390a097e ("CIFS: Add create lease v2 context for SMB3") Signed-off-by: Henrique Carvalho <henrique.carvalho@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01smb: client: add ParentLeaseKey supportHenrique Carvalho
According to MS-SMB2 3.2.4.3.8, when opening a file the client must lookup its parent directory, copy that entry’s LeaseKey into ParentLeaseKey, and set SMB2_LEASE_FLAG_PARENT_LEASE_KEY_SET. Extend lease context functions to carry a parent_lease_key and lease_flags and to add them to the lease context buffer accordingly in smb3_create_lease_buf. Also add a parent_lease_key field to struct cifs_fid and lease_flags to cifs_open_parms. Only applies to the SMB 3.x dialect family. Fixes: f047390a097e ("CIFS: Add create lease v2 context for SMB3") Signed-off-by: Henrique Carvalho <henrique.carvalho@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01cifs: Fix cifs_query_path_info() for Windows NT serversPali Rohár
For TRANS2 QUERY_PATH_INFO request when the path does not exist, the Windows NT SMB server returns error response STATUS_OBJECT_NAME_NOT_FOUND or ERRDOS/ERRbadfile without the SMBFLG_RESPONSE flag set. Similarly it returns STATUS_DELETE_PENDING when the file is being deleted. And looks like that any error response from TRANS2 QUERY_PATH_INFO does not have SMBFLG_RESPONSE flag set. So relax check in check_smb_hdr() for detecting if the packet is response for this special case. This change fixes stat() operation against Windows NT SMB servers and also all operations which depends on -ENOENT result from stat like creat() or mkdir(). Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01cifs: Fix validation of SMB1 query reparse point responsePali Rohár
Validate the SMB1 query reparse point response per [MS-CIFS] section 2.2.7.2 NT_TRANSACT_IOCTL. NT_TRANSACT_IOCTL response contains one word long setup data after which is ByteCount member. So check that SetupCount is 1 before trying to read and use ByteCount member. Output setup data contains ReturnedDataLen member which is the output length of executed IOCTL command by remote system. So check that output was not truncated before transferring over network. Change MaxSetupCount of NT_TRANSACT_IOCTL request from 4 to 1 as io_rsp structure already expects one word long output setup data. This should prevent server sending incompatible structure (in case it would be extended in future, which is unlikely). Change MaxParameterCount of NT_TRANSACT_IOCTL request from 2 to 0 as NT IOCTL does not have any documented output parameters and this function does not parse any output parameters at all. Fixes: ed3e0a149b58 ("smb: client: implement ->query_reparse_point() for SMB1") Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01cifs: Correctly set SMB1 SessionKey field in Session Setup RequestPali Rohár
[MS-CIFS] specification in section 2.2.4.53.1 where is described SMB_COM_SESSION_SETUP_ANDX Request, for SessionKey field says: The client MUST set this field to be equal to the SessionKey field in the SMB_COM_NEGOTIATE Response for this SMB connection. Linux SMB client currently set this field to zero. This is working fine against Windows NT SMB servers thanks to [MS-CIFS] product behavior <94>: Windows NT Server ignores the client's SessionKey. For compatibility with [MS-CIFS], set this SessionKey field in Session Setup Request to value retrieved from Negotiate response. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01cifs: Fix encoding of SMB1 Session Setup NTLMSSP Request in non-UNICODE modePali Rohár
SMB1 Session Setup NTLMSSP Request in non-UNICODE mode is similar to UNICODE mode, just strings are encoded in ASCII and not in UTF-16. With this change it is possible to setup SMB1 session with NTLM authentication in non-UNICODE mode with Windows SMB server. This change fixes mounting SMB1 servers with -o nounicode mount option together with -o sec=ntlmssp mount option (which is the default sec=). Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01smb: client: add NULL check in automount_fullpathRuben Devos
page is checked for null in __build_path_from_dentry_optional_prefix when tcon->origin_fullpath is not set. However, the check is missing when it is set. Add a check to prevent a potential NULL pointer dereference. Signed-off-by: Ruben Devos <devosruben6@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-30Merge tag 'pull-automount' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull automount updates from Al Viro: "Automount wart removal A bunch of odd boilerplate gone from instances - the reason for those was the need to protect the yet-to-be-attched mount from mark_mounts_for_expiry() deciding to take it out. But that's easy to detect and take care of in mark_mounts_for_expiry() itself; no need to have every instance simulate mount being busy by grabbing an extra reference to it, with finish_automount() undoing that once it attaches that mount. Should've done it that way from the very beginning... This is a flagday change, thankfully there are very few instances. vfs_submount() is gone - its sole remaining user (trace_automount) had been switched to saner primitives" * tag 'pull-automount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: kill vfs_submount() saner calling conventions for ->d_automount()
2025-05-28smb: client: Remove an unused function and variableDr. David Alan Gilbert
SMB2_QFS_info() has been unused since 2018's commit 730928c8f4be ("cifs: update smb2_queryfs() to use compounding") sign_CIFS_PDUs has been unused since 2009's commit 2edd6c5b0517 ("[CIFS] NTLMSSP support moving into new file, old dead code removed") Remove them. Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-26Merge tag 'vfs-6.16-rc1.async.dir' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs directory lookup updates from Christian Brauner: "This contains cleanups for the lookup_one*() family of helpers. We expose a set of functions with names containing "lookup_one_len" and others without the "_len". This difference has nothing to do with "len". It's rater a historical accident that can be confusing. The functions without "_len" take a "mnt_idmap" pointer. This is found in the "vfsmount" and that is an important question when choosing which to use: do you have a vfsmount, or are you "inside" the filesystem. A related question is "is permission checking relevant here?". nfsd and cachefiles *do* have a vfsmount but *don't* use the non-_len functions. They pass nop_mnt_idmap and refuse to work on filesystems which have any other idmap. This work changes nfsd and cachefile to use the lookup_one family of functions and to explictily pass &nop_mnt_idmap which is consistent with all other vfs interfaces used where &nop_mnt_idmap is explicitly passed. The remaining uses of the "_one" functions do not require permission checks so these are renamed to be "_noperm" and the permission checking is removed. This series also changes these lookup function to take a qstr instead of separate name and len. In many cases this simplifies the call" * tag 'vfs-6.16-rc1.async.dir' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: VFS: change lookup_one_common and lookup_noperm_common to take a qstr Use try_lookup_noperm() instead of d_hash_and_lookup() outside of VFS VFS: rename lookup_one_len family to lookup_noperm and remove permission check cachefiles: Use lookup_one() rather than lookup_one_len() nfsd: Use lookup_one() rather than lookup_one_len() VFS: improve interface for lookup_one functions
2025-05-23netfs: Fix undifferentiation of DIO reads from unbuffered readsDavid Howells
On cifs, "DIO reads" (specified by O_DIRECT) need to be differentiated from "unbuffered reads" (specified by cache=none in the mount parameters). The difference is flagged in the protocol and the server may behave differently: Windows Server will, for example, mandate that DIO reads are block aligned. Fix this by adding a NETFS_UNBUFFERED_READ to differentiate this from NETFS_DIO_READ, parallelling the write differentiation that already exists. cifs will then do the right thing. Fixes: 016dc8516aec ("netfs: Implement unbuffered/DIO read support") Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/3444961.1747987072@warthog.procyon.org.uk Reviewed-by: "Paulo Alcantara (Red Hat)" <pc@manguebit.com> Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> cc: Steve French <sfrench@samba.org> cc: netfs@lists.linux.dev cc: v9fs@lists.linux.dev cc: linux-afs@lists.infradead.org cc: linux-cifs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-21netfs: Fix the request's work item to not require a refDavid Howells
When the netfs_io_request struct's work item is queued, it must be supplied with a ref to the work item struct to prevent it being deallocated whilst on the queue or whilst it is being processed. This is tricky to manage as we have to get a ref before we try and queue it and then we may find it's already queued and is thus already holding a ref - in which case we have to try and get rid of the ref again. The problem comes if we're in BH or IRQ context and need to drop the ref: if netfs_put_request() reduces the count to 0, we have to do the cleanup - but the cleanup may need to wait. Fix this by adding a new work item to the request, ->cleanup_work, and dispatching that when the refcount hits zero. That can then synchronously cancel any outstanding work on the main work item before doing the cleanup. Adding a new work item also deals with another problem upstream where it's sometimes changing the work func in the put function and requeuing it - which has occasionally in the past caused the cleanup to happen incorrectly. As a bonus, this allows us to get rid of the 'was_async' parameter from a bunch of functions. This indicated whether the put function might not be permitted to sleep. Fixes: 3d3c95046742 ("netfs: Provide readahead and readpage netfs helpers") Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/20250519090707.2848510-4-dhowells@redhat.com cc: Paulo Alcantara <pc@manguebit.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: Steve French <stfrench@microsoft.com> cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-19smb: client: Reset all search buffer pointers when releasing bufferWang Zhaolong
Multiple pointers in struct cifs_search_info (ntwrk_buf_start, srch_entries_start, and last_entry) point to the same allocated buffer. However, when freeing this buffer, only ntwrk_buf_start was set to NULL, while the other pointers remained pointing to freed memory. This is defensive programming to prevent potential issues with stale pointers. While the active UAF vulnerability is fixed by the previous patch, this change ensures consistent pointer state and more robust error handling. Signed-off-by: Wang Zhaolong <wangzhaolong1@huawei.com> Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-18smb: client: Fix use-after-free in cifs_fill_direntWang Zhaolong
There is a race condition in the readdir concurrency process, which may access the rsp buffer after it has been released, triggering the following KASAN warning. ================================================================== BUG: KASAN: slab-use-after-free in cifs_fill_dirent+0xb03/0xb60 [cifs] Read of size 4 at addr ffff8880099b819c by task a.out/342975 CPU: 2 UID: 0 PID: 342975 Comm: a.out Not tainted 6.15.0-rc6+ #240 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x53/0x70 print_report+0xce/0x640 kasan_report+0xb8/0xf0 cifs_fill_dirent+0xb03/0xb60 [cifs] cifs_readdir+0x12cb/0x3190 [cifs] iterate_dir+0x1a1/0x520 __x64_sys_getdents+0x134/0x220 do_syscall_64+0x4b/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f996f64b9f9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0d f7 c3 0c 00 f7 d8 64 89 8 RSP: 002b:00007f996f53de78 EFLAGS: 00000207 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f996f53ecdc RCX: 00007f996f64b9f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f996f53dea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000207 R12: ffffffffffffff88 R13: 0000000000000000 R14: 00007ffc8cd9a500 R15: 00007f996f51e000 </TASK> Allocated by task 408: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x6e/0x70 kmem_cache_alloc_noprof+0x117/0x3d0 mempool_alloc_noprof+0xf2/0x2c0 cifs_buf_get+0x36/0x80 [cifs] allocate_buffers+0x1d2/0x330 [cifs] cifs_demultiplex_thread+0x22b/0x2690 [cifs] kthread+0x394/0x720 ret_from_fork+0x34/0x70 ret_from_fork_asm+0x1a/0x30 Freed by task 342979: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x37/0x50 kmem_cache_free+0x2b8/0x500 cifs_buf_release+0x3c/0x70 [cifs] cifs_readdir+0x1c97/0x3190 [cifs] iterate_dir+0x1a1/0x520 __x64_sys_getdents64+0x134/0x220 do_syscall_64+0x4b/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff8880099b8000 which belongs to the cache cifs_request of size 16588 The buggy address is located 412 bytes inside of freed 16588-byte region [ffff8880099b8000, ffff8880099bc0cc) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x99b8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000 head: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001 head: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000 head: 0080000000000003 ffffea0000266e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880099b8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880099b8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880099b8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880099b8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880099b8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== POC is available in the link [1]. The problem triggering process is as follows: Process 1 Process 2 ----------------------------------------------------------------- cifs_readdir /* file->private_data == NULL */ initiate_cifs_search cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); smb2_query_dir_first ->query_dir_first() SMB2_query_directory SMB2_query_directory_init cifs_send_recv smb2_parse_query_directory srch_inf->ntwrk_buf_start = (char *)rsp; srch_inf->srch_entries_start = (char *)rsp + ... srch_inf->last_entry = (char *)rsp + ... srch_inf->smallBuf = true; find_cifs_entry /* if (cfile->srch_inf.ntwrk_buf_start) */ cifs_small_buf_release(cfile->srch_inf // free cifs_readdir ->iterate_shared() /* file->private_data != NULL */ find_cifs_entry /* in while (...) loop */ smb2_query_dir_next ->query_dir_next() SMB2_query_directory SMB2_query_directory_init cifs_send_recv compound_send_recv smb_send_rqst __smb_send_rqst rc = -ERESTARTSYS; /* if (fatal_signal_pending()) */ goto out; return rc /* if (cfile->srch_inf.last_entry) */ cifs_save_resume_key() cifs_fill_dirent // UAF /* if (rc) */ return -ENOENT; Fix this by ensuring the return code is checked before using pointers from the srch_inf. Link: https://bugzilla.kernel.org/show_bug.cgi?id=220131 [1] Fixes: a364bc0b37f1 ("[CIFS] fix saving of resume key before CIFSFindNext") Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Wang Zhaolong <wangzhaolong1@huawei.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-14smb: client: fix zero rsize error messagesPaulo Alcantara
cifs_prepare_read() might be called with a disconnected channel, where TCP_Server_Info::max_read is set to zero due to reconnect, so calling ->negotiate_rize() will set @rsize to default min IO size (64KiB) and then logging CIFS: VFS: SMB: Zero rsize calculated, using minimum value 65536 If the reconnect happens in cifsd thread, cifs_renegotiate_iosize() will end up being called and then @rsize set to the expected value. Since we can't rely on the value of @server->max_read by the time we call cifs_prepare_read(), try to ->negotiate_rize() only if @cifs_sb->ctx->rsize is zero. Reported-by: Steve French <stfrench@microsoft.com> Fixes: c59f7c9661b9 ("smb: client: ensure aligned IO sizes") Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-14smb: client: fix memory leak during error handling for POSIX mkdirJethro Donaldson
The response buffer for the CREATE request handled by smb311_posix_mkdir() is leaked on the error path (goto err_free_rsp_buf) because the structure pointer *rsp passed to free_rsp_buf() is not assigned until *after* the error condition is checked. As *rsp is initialised to NULL, free_rsp_buf() becomes a no-op and the leak is instead reported by __kmem_cache_shutdown() upon subsequent rmmod of cifs.ko if (and only if) the error path has been hit. Pass rsp_iov.iov_base to free_rsp_buf() instead, similar to the code in other functions in smb2pdu.c for which *rsp is assigned late. Cc: stable@vger.kernel.org Signed-off-by: Jethro Donaldson <devel@jro.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-07smb: client: Avoid race in open_cached_dir with lease breaksPaul Aurich
A pre-existing valid cfid returned from find_or_create_cached_dir might race with a lease break, meaning open_cached_dir doesn't consider it valid, and thinks it's newly-constructed. This leaks a dentry reference if the allocation occurs before the queued lease break work runs. Avoid the race by extending holding the cfid_list_lock across find_or_create_cached_dir and when the result is checked. Cc: stable@vger.kernel.org Reviewed-by: Henrique Carvalho <henrique.carvalho@suse.com> Signed-off-by: Paul Aurich <paul@darkrain42.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-06smb3 client: warn when parse contexts returns error on compounded operationSteve French
Coverity noticed that the rc on smb2_parse_contexts() was not being checked in the case of compounded operations. Since we don't want to stop parsing the following compounded responses which are likely valid, we can't easily error out here, but at least print a warning message if server has a bug causing us to skip parsing the open response contexts. Addresses-Coverity: 1639191 Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-05saner calling conventions for ->d_automount()Al Viro
Currently the calling conventions for ->d_automount() instances have an odd wart - returned new mount to be attached is expected to have refcount 2. That kludge is intended to make sure that mark_mounts_for_expiry() called before we get around to attaching that new mount to the tree won't decide to take it out. finish_automount() drops the extra reference after it's done with attaching mount to the tree - or drops the reference twice in case of error. ->d_automount() instances have rather counterintuitive boilerplate in them. There's a much simpler approach: have mark_mounts_for_expiry() skip the mounts that are yet to be mounted. And to hell with grabbing/dropping those extra references. Makes for simpler correctness analysis, at that... Reviewed-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Acked-by: David Howells <dhowells@redhat.com> Tested-by: David Howells <dhowells@redhat.com> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-05-01smb: client: ensure aligned IO sizesPaulo Alcantara
Make all IO sizes multiple of PAGE_SIZE, either negotiated by the server or passed through rsize, wsize and bsize mount options, to prevent from breaking DIO reads and writes against servers that enforce alignment as specified in MS-FSA 2.1.5.3 and 2.1.5.4. Cc: linux-cifs@vger.kernel.org Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-30cifs: Fix changing times and read-only attr over SMB1 smb_set_file_info() ↵Pali Rohár
function Function CIFSSMBSetPathInfo() is not supported by non-NT servers and returns error. Fallback code via open filehandle and CIFSSMBSetFileInfo() does not work neither because CIFS_open() works also only on NT server. Therefore currently the whole smb_set_file_info() function as a SMB1 callback for the ->set_file_info() does not work with older non-NT SMB servers, like Win9x and others. This change implements fallback code in smb_set_file_info() which will works with any server and allows to change time values and also to set or clear read-only attributes. To make existing fallback code via CIFSSMBSetFileInfo() working with also non-NT servers, it is needed to change open function from CIFS_open() (which is NT specific) to cifs_open_file() which works with any server (this is just a open wrapper function which choose the correct open function supported by the server). CIFSSMBSetFileInfo() is working also on non-NT servers, but zero time values are not treated specially. So first it is needed to fill all time values if some of them are missing, via cifs_query_path_info() call. There is another issue, opening file in write-mode (needed for changing attributes) is not possible when the file has read-only attribute set. The only option how to clear read-only attribute is via SMB_COM_SETATTR command. And opening directory is not possible neither and here the SMB_COM_SETATTR command is the only option how to change attributes. And CIFSSMBSetFileInfo() does not honor setting read-only attribute, so for setting is also needed to use SMB_COM_SETATTR command. Existing code in cifs_query_path_info() is already using SMB_COM_GETATTR as a fallback code path (function SMBQueryInformation()), so introduce a new function SMBSetInformation which will implement SMB_COM_SETATTR command. My testing showed that Windows XP SMB1 client is also using SMB_COM_SETATTR command for setting or clearing read-only attribute against non-NT server. So this can prove that this is the correct way how to do it. With this change it is possible set all 4 time values and all attributes, including clearing and setting read-only bit on non-NT SMB servers. Tested against Win98 SMB1 server. This change fixes "touch" command which was failing when called on existing file. And fixes also "chmod +w" and "chmod -w" commands which were also failing (as they are changing read-only attribute). Note that this change depends on following change "cifs: Improve cifs_query_path_info() and cifs_query_file_info()" as it require to query all 4 time attribute values. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-30cifs: Fix and improve cifs_query_path_info() and cifs_query_file_info()Pali Rohár
When CAP_NT_SMBS was not negotiated then do not issue CIFSSMBQPathInfo() and CIFSSMBQFileInfo() commands. CIFSSMBQPathInfo() is not supported by non-NT Win9x SMB server and CIFSSMBQFileInfo() returns from Win9x SMB server bogus data in Attributes field (for example lot of files are marked as reparse points, even Win9x does not support them and read-only bit is not marked for read-only files). Correct information is returned by CIFSFindFirst() or SMBQueryInformation() command. So as a fallback in cifs_query_path_info() function use CIFSFindFirst() with SMB_FIND_FILE_FULL_DIRECTORY_INFO level which is supported by both NT and non-NT servers and as a last option use SMBQueryInformation() as it was before. And in function cifs_query_file_info() immediately returns -EOPNOTSUPP when not communicating with NT server. Client then revalidate inode entry by the cifs_query_path_info() call, which is working fine. So fstat() syscall on already opened file will receive correct information. Note that both fallback functions in non-UNICODE mode expands wildcards. Therefore those fallback functions cannot be used on paths which contain SMB wildcard characters (* ? " > <). CIFSFindFirst() returns all 4 time attributes as opposite of SMBQueryInformation() which returns only one. With this change it is possible to query all 4 times attributes from Win9x server and at the same time, client minimize sending of unsupported commands to server. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-30smb: client: fix zero length for mkdir POSIX create contextJethro Donaldson
SMB create requests issued via smb311_posix_mkdir() have an incorrect length of zero bytes for the POSIX create context data. ksmbd server rejects such requests and logs "cli req too short" causing mkdir to fail with "invalid argument" on the client side. It also causes subsequent rmmod to crash in cifs_destroy_request_bufs() Inspection of packets sent by cifs.ko using wireshark show valid data for the SMB2_POSIX_CREATE_CONTEXT is appended with the correct offset, but with an incorrect length of zero bytes. Fails with ksmbd+cifs.ko only as Windows server/client does not use POSIX extensions. Fix smb311_posix_mkdir() to set req->CreateContextsLength as part of appending the POSIX creation context to the request. Signed-off-by: Jethro Donaldson <devel@jro.nz> Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Reviewed-by: Namjae Jeon <linkinjeon@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-13Revert "smb: client: fix TCP timers deadlock after rmmod"Kuniyuki Iwashima
This reverts commit e9f2517a3e18a54a3943c098d2226b245d488801. Commit e9f2517a3e18 ("smb: client: fix TCP timers deadlock after rmmod") is intended to fix a null-ptr-deref in LOCKDEP, which is mentioned as CVE-2024-54680, but is actually did not fix anything; The issue can be reproduced on top of it. [0] Also, it reverted the change by commit ef7134c7fc48 ("smb: client: Fix use-after-free of network namespace.") and introduced a real issue by reviving the kernel TCP socket. When a reconnect happens for a CIFS connection, the socket state transitions to FIN_WAIT_1. Then, inet_csk_clear_xmit_timers_sync() in tcp_close() stops all timers for the socket. If an incoming FIN packet is lost, the socket will stay at FIN_WAIT_1 forever, and such sockets could be leaked up to net.ipv4.tcp_max_orphans. Usually, FIN can be retransmitted by the peer, but if the peer aborts the connection, the issue comes into reality. I warned about this privately by pointing out the exact report [1], but the bogus fix was finally merged. So, we should not stop the timers to finally kill the connection on our side in that case, meaning we must not use a kernel socket for TCP whose sk->sk_net_refcnt is 0. The kernel socket does not have a reference to its netns to make it possible to tear down netns without cleaning up every resource in it. For example, tunnel devices use a UDP socket internally, but we can destroy netns without removing such devices and let it complete during exit. Otherwise, netns would be leaked when the last application died. However, this is problematic for TCP sockets because TCP has timers to close the connection gracefully even after the socket is close()d. The lifetime of the socket and its netns is different from the lifetime of the underlying connection. If the socket user does not maintain the netns lifetime, the timer could be fired after the socket is close()d and its netns is freed up, resulting in use-after-free. Actually, we have seen so many similar issues and converted such sockets to have a reference to netns. That's why I converted the CIFS client socket to have a reference to netns (sk->sk_net_refcnt == 1), which is somehow mentioned as out-of-scope of CIFS and technically wrong in e9f2517a3e18, but **is in-scope and right fix**. Regarding the LOCKDEP issue, we can prevent the module unload by bumping the module refcount when switching the LOCKDDEP key in sock_lock_init_class_and_name(). [2] For a while, let's revert the bogus fix. Note that now we can use sk_net_refcnt_upgrade() for the socket conversion, but I'll do so later separately to make backport easy. Link: https://lore.kernel.org/all/20250402020807.28583-1-kuniyu@amazon.com/ #[0] Link: https://lore.kernel.org/netdev/c08bd5378da647a2a4c16698125d180a@huawei.com/ #[1] Link: https://lore.kernel.org/lkml/20250402005841.19846-1-kuniyu@amazon.com/ #[2] Fixes: e9f2517a3e18 ("smb: client: fix TCP timers deadlock after rmmod") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-13Revert "smb: client: Fix netns refcount imbalance causing leaks and ↵Kuniyuki Iwashima
use-after-free" This reverts commit 4e7f1644f2ac6d01dc584f6301c3b1d5aac4eaef. The commit e9f2517a3e18 ("smb: client: fix TCP timers deadlock after rmmod") is not only a bogus fix for LOCKDEP null-ptr-deref but also introduces a real issue, TCP sockets leak, which will be explained in detail in the next revert. Also, CNA assigned CVE-2024-54680 to it but is rejecting it. [0] Thus, we are reverting the commit and its follow-up commit 4e7f1644f2ac ("smb: client: Fix netns refcount imbalance causing leaks and use-after-free"). Link: https://lore.kernel.org/all/2025040248-tummy-smilingly-4240@gregkh/ #[0] Fixes: 4e7f1644f2ac ("smb: client: Fix netns refcount imbalance causing leaks and use-after-free") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-13smb3 client: fix open hardlink on deferred close file errorChunjie Zhu
The following Python script results in unexpected behaviour when run on a CIFS filesystem against a Windows Server: # Create file fd = os.open('test', os.O_WRONLY|os.O_CREAT) os.write(fd, b'foo') os.close(fd) # Open and close the file to leave a pending deferred close fd = os.open('test', os.O_RDONLY|os.O_DIRECT) os.close(fd) # Try to open the file via a hard link os.link('test', 'new') newfd = os.open('new', os.O_RDONLY|os.O_DIRECT) The final open returns EINVAL due to the server returning STATUS_INVALID_PARAMETER. The root cause of this is that the client caches lease keys per inode, but the spec requires them to be related to the filename which causes problems when hard links are involved: From MS-SMB2 section 3.3.5.9.11: "The server MUST attempt to locate a Lease by performing a lookup in the LeaseTable.LeaseList using the LeaseKey in the SMB2_CREATE_REQUEST_LEASE_V2 as the lookup key. If a lease is found, Lease.FileDeleteOnClose is FALSE, and Lease.Filename does not match the file name for the incoming request, the request MUST be failed with STATUS_INVALID_PARAMETER" On client side, we first check the context of file open, if it hits above conditions, we first close all opening files which are belong to the same inode, then we do open the hard link file. Cc: stable@vger.kernel.org Signed-off-by: Chunjie Zhu <chunjie.zhu@cloud.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09smb3: Add defines for two new FileSystemAttributesSteve French
Two new file system attributes were recently added. See MS-FSCC 2.5.1: FILE_SUPPORTS_POSIX_UNLINK_RENAME and FILE_RETURNS_CLEANUP_RESULT_INFO Update the missing defines for ksmbd and cifs.ko Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09cifs: Fix querying of WSL CHR and BLK reparse points over SMB1Pali Rohár
When reparse point in SMB1 query_path_info() callback was detected then query also for EA $LXDEV. In this EA are stored device major and minor numbers used by WSL CHR and BLK reparse points. Without major and minor numbers, stat() syscall does not work for char and block devices. Similar code is already in SMB2+ query_path_info() callback function. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09cifs: Split parse_reparse_point callback to functions: get buffer and parse ↵Pali Rohár
buffer Parsing reparse point buffer is generic for all SMB versions and is already implemented by global function parse_reparse_point(). Getting reparse point buffer from the SMB response is SMB version specific, so introduce for it a new callback get_reparse_point_buffer. This functionality split is needed for followup change - getting reparse point buffer without parsing it. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09cifs: Improve handling of name surrogate reparse points in reparse.cPali Rohár
Like previous changes for file inode.c, handle directory name surrogate reparse points generally also in reparse.c. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09cifs: Remove explicit handling of IO_REPARSE_TAG_MOUNT_POINT in inode.cPali Rohár
IO_REPARSE_TAG_MOUNT_POINT is just a specific case of directory Name Surrogate reparse point. As reparse_info_to_fattr() already handles all directory Name Surrogate reparse point (done by the previous change), there is no need to have explicit case for IO_REPARSE_TAG_MOUNT_POINT. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09cifs: Fix encoding of SMB1 Session Setup Kerberos Request in non-UNICODE modePali Rohár
Like in UNICODE mode, SMB1 Session Setup Kerberos Request contains oslm and domain strings. Extract common code into ascii_oslm_strings() and ascii_domain_string() functions (similar to unicode variants) and use these functions in non-UNICODE code path in sess_auth_kerberos(). Decision if non-UNICODE or UNICODE mode is used is based on the SMBFLG2_UNICODE flag in Flags2 packed field, and not based on the capabilities of server. Fix this check too. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09smb: client: fix UAF in decryption with multichannelPaulo Alcantara
After commit f7025d861694 ("smb: client: allocate crypto only for primary server") and commit b0abcd65ec54 ("smb: client: fix UAF in async decryption"), the channels started reusing AEAD TFM from primary channel to perform synchronous decryption, but that can't done as there could be multiple cifsd threads (one per channel) simultaneously accessing it to perform decryption. This fixes the following KASAN splat when running fstest generic/249 with 'vers=3.1.1,multichannel,max_channels=4,seal' against Windows Server 2022: BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xba/0x110 Read of size 8 at addr ffff8881046c18a0 by task cifsd/986 CPU: 3 UID: 0 PID: 986 Comm: cifsd Not tainted 6.15.0-rc1 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x80 print_report+0x156/0x528 ? gf128mul_4k_lle+0xba/0x110 ? __virt_addr_valid+0x145/0x300 ? __phys_addr+0x46/0x90 ? gf128mul_4k_lle+0xba/0x110 kasan_report+0xdf/0x1a0 ? gf128mul_4k_lle+0xba/0x110 gf128mul_4k_lle+0xba/0x110 ghash_update+0x189/0x210 shash_ahash_update+0x295/0x370 ? __pfx_shash_ahash_update+0x10/0x10 ? __pfx_shash_ahash_update+0x10/0x10 ? __pfx_extract_iter_to_sg+0x10/0x10 ? ___kmalloc_large_node+0x10e/0x180 ? __asan_memset+0x23/0x50 crypto_ahash_update+0x3c/0xc0 gcm_hash_assoc_remain_continue+0x93/0xc0 crypt_message+0xe09/0xec0 [cifs] ? __pfx_crypt_message+0x10/0x10 [cifs] ? _raw_spin_unlock+0x23/0x40 ? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs] decrypt_raw_data+0x229/0x380 [cifs] ? __pfx_decrypt_raw_data+0x10/0x10 [cifs] ? __pfx_cifs_read_iter_from_socket+0x10/0x10 [cifs] smb3_receive_transform+0x837/0xc80 [cifs] ? __pfx_smb3_receive_transform+0x10/0x10 [cifs] ? __pfx___might_resched+0x10/0x10 ? __pfx_smb3_is_transform_hdr+0x10/0x10 [cifs] cifs_demultiplex_thread+0x692/0x1570 [cifs] ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] ? rcu_is_watching+0x20/0x50 ? rcu_lockdep_current_cpu_online+0x62/0xb0 ? find_held_lock+0x32/0x90 ? kvm_sched_clock_read+0x11/0x20 ? local_clock_noinstr+0xd/0xd0 ? trace_irq_enable.constprop.0+0xa8/0xe0 ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] kthread+0x1fe/0x380 ? kthread+0x10f/0x380 ? __pfx_kthread+0x10/0x10 ? local_clock_noinstr+0xd/0xd0 ? ret_from_fork+0x1b/0x60 ? local_clock+0x15/0x30 ? lock_release+0x29b/0x390 ? rcu_is_watching+0x20/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Tested-by: David Howells <dhowells@redhat.com> Reported-by: Steve French <stfrench@microsoft.com> Closes: https://lore.kernel.org/r/CAH2r5mu6Yc0-RJXM3kFyBYUB09XmXBrNodOiCVR4EDrmxq5Szg@mail.gmail.com Fixes: f7025d861694 ("smb: client: allocate crypto only for primary server") Fixes: b0abcd65ec54 ("smb: client: fix UAF in async decryption") Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-08cifs: Fix support for WSL-style symlinksPali Rohár
MS-FSCC in section 2.1.2.7 LX SYMLINK REPARSE_DATA_BUFFER now contains documentation about WSL symlink reparse point buffers. https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-fscc/68337353-9153-4ee1-ac6b-419839c3b7ad Fix the struct reparse_wsl_symlink_data_buffer to reflect buffer fields according to the MS-FSCC documentation. Fix the Linux SMB client to correctly fill the WSL symlink reparse point buffer when creaing new WSL-style symlink. There was a mistake during filling the data part of the reparse point buffer. It should starts with bytes "\x02\x00\x00\x00" (which represents version 2) but this constant was written as number 0x02000000 encoded in little endian, which resulted bytes "\x00\x00\x00\x02". This change is fixing this mistake. Fixes: 4e2043be5c14 ("cifs: Add support for creating WSL-style symlinks") Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-08Use try_lookup_noperm() instead of d_hash_and_lookup() outside of VFSNeilBrown
try_lookup_noperm() and d_hash_and_lookup() are nearly identical. The former does some validation of the name where the latter doesn't. Outside of the VFS that validation is likely valuable, and having only one exported function for this task is certainly a good idea. So make d_hash_and_lookup() local to VFS files and change all other callers to try_lookup_noperm(). Note that the arguments are swapped. Signed-off-by: NeilBrown <neilb@suse.de> Link: https://lore.kernel.org/r/20250319031545.2999807-6-neil@brown.name Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-08VFS: rename lookup_one_len family to lookup_noperm and remove permission checkNeilBrown
The lookup_one_len family of functions is (now) only used internally by a filesystem on itself either - in a context where permission checking is irrelevant such as by a virtual filesystem populating itself, or xfs accessing its ORPHANAGE or dquota accessing the quota file; or - in a context where a permission check (MAY_EXEC on the parent) has just been performed such as a network filesystem finding in "silly-rename" file in the same directory. This is also the context after the _parentat() functions where currently lookup_one_qstr_excl() is used. So the permission check is pointless. The name "one_len" is unhelpful in understanding the purpose of these functions and should be changed. Most of the callers pass the len as "strlen()" so using a qstr and QSTR() can simplify the code. This patch renames these functions (include lookup_positive_unlocked() which is part of the family despite the name) to have a name based on "lookup_noperm". They are changed to receive a 'struct qstr' instead of separate name and len. In a few cases the use of QSTR() results in a new call to strlen(). try_lookup_noperm() takes a pointer to a qstr instead of the whole qstr. This is consistent with d_hash_and_lookup() (which is nearly identical) and useful for lookup_noperm_unlocked(). The new lookup_noperm_common() doesn't take a qstr yet. That will be tidied up in a subsequent patch. Signed-off-by: NeilBrown <neil@brown.name> Link: https://lore.kernel.org/r/20250319031545.2999807-5-neil@brown.name Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07smb311 client: fix missing tcon check when mounting with linux/posix extensionsSteve French
When mounting the same share twice, once with the "linux" mount parameter (or equivalently "posix") and then once without (or e.g. with "nolinux"), we were incorrectly reusing the same tree connection for both mounts. This meant that the first mount of the share on the client, would cause subsequent mounts of that same share on the same client to ignore that mount parm ("linux" vs. "nolinux") and incorrectly reuse the same tcon. Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-07cifs: Ensure that all non-client-specific reparse points are processed by ↵Pali Rohár
the server Fix regression in mounts to e.g. onedrive shares. Generally, reparse points are processed by the SMB server during the SMB OPEN request, but there are few reparse points which do not have OPEN-like meaning for the SMB server and has to be processed by the SMB client. Those are symlinks and special files (fifo, socket, block, char). For Linux SMB client, it is required to process also name surrogate reparse points as they represent another entity on the SMB server system. Linux client will mark them as separate mount points. Examples of name surrogate reparse points are NTFS junction points (e.g. created by the "mklink" tool on Windows servers). So after processing the name surrogate reparse points, clear the -EOPNOTSUPP error code returned from the parse_reparse_point() to let SMB server to process reparse points. And remove printing misleading error message "unhandled reparse tag:" as reparse points are handled by SMB server and hence unhandled fact is normal operation. Fixes: cad3fc0a4c8c ("cifs: Throw -EOPNOTSUPP error on unsupported reparse point type from parse_reparse_point()") Fixes: b587fd128660 ("cifs: Treat unhandled directory name surrogate reparse points as mount directory nodes") Cc: stable@vger.kernel.org Reported-by: Junwen Sun <sunjw8888@gmail.com> Tested-by: Junwen Sun <sunjw8888@gmail.com> Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-02cifs: update internal version numberSteve French
To 2.52 Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-02cifs: Implement is_network_name_deleted for SMB1Pali Rohár
This change allows Linux SMB1 client to autoreconnect the share when it is modified on server by admin operation which removes and re-adds it. Implementation is reused from SMB2+ is_network_name_deleted callback. There are just adjusted checks for error codes and access to struct smb_hdr. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-02cifs: Remove cifs_truncate_page() as it should be superfluousDavid Howells
The calls to cifs_truncate_page() should be superfluous as the places that call it also call truncate_setsize() or cifs_setsize() and therefore truncate_pagecache() which should also clear the tail part of the folio containing the EOF marker. Further, smb3_simple_falloc() calls both cifs_setsize() and truncate_setsize() in addition to cifs_truncate_page(). Remove the superfluous calls. This gets rid of another function referring to struct page. [Should cifs_setsize() also set inode->i_blocks?] Signed-off-by: David Howells <dhowells@redhat.com> cc: Steve French <stfrench@microsoft.com> Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com> cc: Matthew Wilcox <willy@infradead.org> cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALLPali Rohár
Individual bits GENERIC_READ, GENERIC_EXECUTE and GENERIC_ALL have meaning which includes also access right for FILE_READ_ATTRIBUTES. So specifying FILE_READ_ATTRIBUTES bit together with one of those GENERIC (except GENERIC_WRITE) does not do anything. This change prevents calling additional (fallback) code and sending more requests without FILE_READ_ATTRIBUTES when the primary request fails on -EACCES, as it is not needed at all. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01cifs: Improve SMB2+ stat() to work also without FILE_READ_ATTRIBUTESPali Rohár
If SMB2_OP_QUERY_INFO (called when POSIX extensions are not used) failed with STATUS_ACCESS_DENIED then it means that caller does not have permission to open the path with FILE_READ_ATTRIBUTES access and therefore cannot issue SMB2_OP_QUERY_INFO command. This will result in the -EACCES error from stat() sycall. There is an alternative way how to query limited information about path but still suitable for stat() syscall. SMB2 OPEN/CREATE operation returns in its successful response subset of query information. So try to open the path without FILE_READ_ATTRIBUTES but with MAXIMUM_ALLOWED access which will grant the maximum possible access to the file and the response will contain required query information for stat() syscall. This will improve smb2_query_path_info() to query also files which do not grant FILE_READ_ATTRIBUTES access to caller. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01cifs: Add fallback for SMB2 CREATE without FILE_READ_ATTRIBUTESPali Rohár
Some operations, like WRITE, does not require FILE_READ_ATTRIBUTES access. So when FILE_READ_ATTRIBUTES is not explicitly requested for smb2_open_file() then first try to do SMB2 CREATE with FILE_READ_ATTRIBUTES access (like it was before) and then fallback to SMB2 CREATE without FILE_READ_ATTRIBUTES access (less common case). This change allows to complete WRITE operation to a file when it does not grant FILE_READ_ATTRIBUTES permission and its parent directory does not grant READ_DATA permission (parent directory READ_DATA is implicit grant of child FILE_READ_ATTRIBUTES permission). Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01cifs: Fix querying and creating MF symlinks over SMB1Pali Rohár
Old SMB1 servers without CAP_NT_SMBS do not support CIFS_open() function and instead SMBLegacyOpen() needs to be used. This logic is already handled in cifs_open_file() function, which is server->ops->open callback function. So for querying and creating MF symlinks use open callback function instead of CIFS_open() function directly. This change fixes querying and creating new MF symlinks on Windows 98. Currently cifs_query_mf_symlink() is not able to detect MF symlink and cifs_create_mf_symlink() is failing with EIO error. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01cifs: Fix access_flags_to_smbopen_modePali Rohár
When converting access_flags to SMBOPEN mode, check for all possible access flags, not only GENERIC_READ and GENERIC_WRITE flags. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01cifs: Fix negotiate retry functionalityPali Rohár
SMB negotiate retry functionality in cifs_negotiate() is currently broken and does not work when doing socket reconnect. Caller of this function, which is cifs_negotiate_protocol() requires that tcpStatus after successful execution of negotiate callback stay in CifsInNegotiate. But if the CIFSSMBNegotiate() called from cifs_negotiate() fails due to connection issues then tcpStatus is changed as so repeated CIFSSMBNegotiate() call does not help. Fix this problem by moving retrying code from negotiate callback (which is either cifs_negotiate() or smb2_negotiate()) to cifs_negotiate_protocol() which is caller of those callbacks. This allows to properly handle and implement correct transistions between tcpStatus states as function cifs_negotiate_protocol() already handles it. With this change, cifs_negotiate_protocol() now handles also -EAGAIN error set by the RFC1002_NEGATIVE_SESSION_RESPONSE processing after reconnecting with NetBIOS session. Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>