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path: root/fs/cifs/inode.c
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2020-05-06CIFS: Spelling s/EACCESS/EACCES/Geert Uytterhoeven
As per POSIX, the correct spelling is EACCES: include/uapi/asm-generic/errno-base.h:#define EACCES 13 /* Permission denied */ Fixes: b8f7442bc46e48fb ("CIFS: refactor cifs_get_inode_info()") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-15cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+Jones Syue
Found a read performance issue when linux kernel page size is 64KB. If linux kernel page size is 64KB and mount options cache=strict & vers=2.1+, it does not support cifs_readpages(). Instead, it is using cifs_readpage() and cifs_read() with maximum read IO size 16KB, which is much slower than read IO size 1MB when negotiated SMB 2.1+. Since modern SMB server supported SMB 2.1+ and Max Read Size can reach more than 64KB (for example 1MB ~ 8MB), this patch check max_read instead of maxBuf to determine whether server support readpages() and improve read performance for page size 64KB & cache=strict & vers=2.1+, and for SMB1 it is more cleaner to initialize server->max_read to server->maxBuf. The client is a linux box with linux kernel 4.2.8, page size 64KB (CONFIG_ARM64_64K_PAGES=y), cpu arm 1.7GHz, and use mount.cifs as smb client. The server is another linux box with linux kernel 4.2.8, share a file '10G.img' with size 10GB, and use samba-4.7.12 as smb server. The client mount a share from the server with different cache options: cache=strict and cache=none, mount -tcifs //<server_ip>/Public /cache_strict -overs=3.0,cache=strict,username=<xxx>,password=<yyy> mount -tcifs //<server_ip>/Public /cache_none -overs=3.0,cache=none,username=<xxx>,password=<yyy> The client download a 10GbE file from the server across 1GbE network, dd if=/cache_strict/10G.img of=/dev/null bs=1M count=10240 dd if=/cache_none/10G.img of=/dev/null bs=1M count=10240 Found that cache=strict (without patch) is slower read throughput and smaller read IO size than cache=none. cache=strict (without patch): read throughput 40MB/s, read IO size is 16KB cache=strict (with patch): read throughput 113MB/s, read IO size is 1MB cache=none: read throughput 109MB/s, read IO size is 1MB Looks like if page size is 64KB, cifs_set_ops() would use cifs_addr_ops_smallbuf instead of cifs_addr_ops, /* check if server can support readpages */ if (cifs_sb_master_tcon(cifs_sb)->ses->server->maxBuf < PAGE_SIZE + MAX_CIFS_HDR_SIZE) inode->i_data.a_ops = &cifs_addr_ops_smallbuf; else inode->i_data.a_ops = &cifs_addr_ops; maxBuf is came from 2 places, SMB2_negotiate() and CIFSSMBNegotiate(), (SMB2_MAX_BUFFER_SIZE is 64KB) SMB2_negotiate(): /* set it to the maximum buffer size value we can send with 1 credit */ server->maxBuf = min_t(unsigned int, le32_to_cpu(rsp->MaxTransactSize),       SMB2_MAX_BUFFER_SIZE); CIFSSMBNegotiate(): server->maxBuf = le32_to_cpu(pSMBr->MaxBufferSize); Page size 64KB and cache=strict lead to read_pages() use cifs_readpage() instead of cifs_readpages(), and then cifs_read() using maximum read IO size 16KB, which is much slower than maximum read IO size 1MB. (CIFSMaxBufSize is 16KB by default) /* FIXME: set up handlers for larger reads and/or convert to async */ rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize); Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Jones Syue <jonessyue@qnap.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-04-10smb3: enable swap on SMB3 mountsSteve French
Add experimental support for allowing a swap file to be on an SMB3 mount. There are use cases where swapping over a secure network filesystem is preferable. In some cases there are no local block devices large enough, and network block devices can be hard to setup and secure. And in some cases there are no local block devices at all (e.g. with the recent addition of remote boot over SMB3 mounts). There are various enhancements that can be added later e.g.: - doing a mandatory byte range lock over the swapfile (until the Linux VFS is modified to notify the file system that an open is for a swapfile, when the file can be opened "DENY_ALL" to prevent others from opening it). - pinning more buffers in the underlying transport to minimize memory allocations in the TCP stack under the fs - documenting how to create ACLs (on the server) to secure the swapfile (or adding additional tools to cifs-utils to make it easier) Signed-off-by: Steve French <stfrench@microsoft.com> Acked-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-03-22cifs: do d_move in renameSteve French
See commit 349457ccf2592c14bdf13b6706170ae2e94931b1 "Allow file systems to manually d_move() inside of ->rename()" Lessens possibility of race conditions in rename Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22smb3: fix performance regression with setting mtimeSteve French
There are cases when we don't want to send the SMB2 flush operation (e.g. when user specifies mount parm "nostrictsync") and it can be a very expensive operation on the server. In most cases in order to set mtime, we simply need to flush (write) the dirtry pages from the client and send the writes to the server not also send a flush protocol operation to the server. Fixes: aa081859b10c ("cifs: flush before set-info if we have writeable handles") CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22cifs: do not ignore the SYNC flags in getattrSteve French
Check the AT_STATX_FORCE_SYNC flag and force an attribute revalidation if requested by the caller, and if the caller specificies AT_STATX_DONT_SYNC only revalidate cached attributes if required. In addition do not flush writes in getattr (which can be expensive) if size or timestamps not requested by the caller. Reviewed-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-17cifs: potential unintitliazed error code in cifs_getattr()Dan Carpenter
Smatch complains that "rc" could be uninitialized. fs/cifs/inode.c:2206 cifs_getattr() error: uninitialized symbol 'rc'. Changing it to "return 0;" improves readability as well. Fixes: cc1baf98c8f6 ("cifs: do not ignore the SYNC flags in getattr") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steve French <stfrench@microsoft.com> Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-02-24cifs: Use #define in cifs_dbgJoe Perches
All other uses of cifs_dbg use defines so change this one. Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-24cifs: fix rename() by ensuring source handle opened with DELETE bitAurelien Aptel
To rename a file in SMB2 we open it with the DELETE access and do a special SetInfo on it. If the handle is missing the DELETE bit the server will fail the SetInfo with STATUS_ACCESS_DENIED. We currently try to reuse any existing opened handle we have with cifs_get_writable_path(). That function looks for handles with WRITE access but doesn't check for DELETE, making rename() fail if it finds a handle to reuse. Simple reproducer below. To select handles with the DELETE bit, this patch adds a flag argument to cifs_get_writable_path() and find_writable_file() and the existing 'bool fsuid_only' argument is converted to a flag. The cifsFileInfo struct only stores the UNIX open mode but not the original SMB access flags. Since the DELETE bit is not mapped in that mode, this patch stores the access mask in cifs_fid on file open, which is accessible from cifsFileInfo. Simple reproducer: #include <stdio.h> #include <stdlib.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> #define E(s) perror(s), exit(1) int main(int argc, char *argv[]) { int fd, ret; if (argc != 3) { fprintf(stderr, "Usage: %s A B\n" "create&open A in write mode, " "rename A to B, close A\n", argv[0]); return 0; } fd = openat(AT_FDCWD, argv[1], O_WRONLY|O_CREAT|O_SYNC, 0666); if (fd == -1) E("openat()"); ret = rename(argv[1], argv[2]); if (ret) E("rename()"); ret = close(fd); if (ret) E("close()"); return ret; } $ gcc -o bugrename bugrename.c $ ./bugrename /mnt/a /mnt/b rename(): Permission denied Fixes: 8de9e86c67ba ("cifs: create a helper to find a writeable handle by path name") CC: Stable <stable@vger.kernel.org> Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
2020-02-24cifs: don't leak -EAGAIN for stat() during reconnectRonnie Sahlberg
If from cifs_revalidate_dentry_attr() the SMB2/QUERY_INFO call fails with an error, such as STATUS_SESSION_EXPIRED, causing the session to be reconnected it is possible we will leak -EAGAIN back to the application even for system calls such as stat() where this is not a valid error. Fix this by re-trying the operation from within cifs_revalidate_dentry_attr() if cifs_get_inode_info*() returns -EAGAIN. This fixes stat() and possibly also other system calls that uses cifs_revalidate_dentry*(). Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> CC: Stable <stable@vger.kernel.org>
2020-02-12cifs: Fix mode output in debugging statementsFrank Sorenson
A number of the debug statements output file or directory mode in hex. Change these to print using octal. Signed-off-by: Frank Sorenson <sorenson@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-02-09Merge tag '5.6-rc-smb3-plugfest-patches' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs fixes from Steve French: "13 cifs/smb3 patches, most from testing at the SMB3 plugfest this week: - Important fix for multichannel and for modefromsid mounts. - Two reconnect fixes - Addition of SMB3 change notify support - Backup tools fix - A few additional minor debug improvements (tracepoints and additional logging found useful during testing this week)" * tag '5.6-rc-smb3-plugfest-patches' of git://git.samba.org/sfrench/cifs-2.6: smb3: Add defines for new information level, FileIdInformation smb3: print warning once if posix context returned on open smb3: add one more dynamic tracepoint missing from strict fsync path cifs: fix mode bits from dir listing when mounted with modefromsid cifs: fix channel signing cifs: add SMB3 change notification support cifs: make multichannel warning more visible cifs: fix soft mounts hanging in the reconnect code cifs: Add tracepoints for errors on flush or fsync cifs: log warning message (once) if out of disk space cifs: fail i/o on soft mounts if sessionsetup errors out smb3: fix problem with null cifs super block with previous patch SMB3: Backup intent flag missing from some more ops
2020-02-05Merge branch 'imm.timestamp' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs timestamp updates from Al Viro: "More 64bit timestamp work" * 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: kernfs: don't bother with timestamp truncation fs: Do not overload update_time fs: Delete timespec64_trunc() fs: ubifs: Eliminate timespec64_trunc() usage fs: ceph: Delete timespec64_trunc() usage fs: cifs: Delete usage of timespec64_trunc fs: fat: Eliminate timespec64_trunc() usage utimes: Clamp the timestamps in notify_change()
2020-02-03SMB3: Backup intent flag missing from some more opsAmir Goldstein
When "backup intent" is requested on the mount (e.g. backupuid or backupgid mount options), the corresponding flag was missing from some of the operations. Change all operations to use the macro cifs_create_options() to set the backup intent flag if needed. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-01-26cifs: add support for fallocate mode 0 for non-sparse filesRonnie Sahlberg
RHBZ 1336264 When we extend a file we must also force the size to be updated. This fixes an issue with holetest in xfs-tests which performs the following sequence : 1, create a new file 2, use fallocate mode==0 to populate the file 3, mmap the file 4, touch each page by reading the mmapped region. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-12-08fs: cifs: Delete usage of timespec64_truncDeepa Dinamani
timestamp_truncate() is the replacement api for timespec64_trunc. timestamp_truncate() additionally clamps timestamps to make sure the timestamps lie within the permitted range for the filesystem. Truncate the timestamps in the struct cifs_attr at the site of assignment to inode times. This helps us use the right fs api timestamp_trucate() to perform the truncation. Also update the ktime_get_* api to match the one used in current_time(). This allows for timestamps to be updated the same way always. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Cc: stfrench@microsoft.com Cc: linux-cifs@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-12-02fs: cifs: Fix atime update check vs mtimeDeepa Dinamani
According to the comment in the code and commit log, some apps expect atime >= mtime; but the introduced code results in atime==mtime. Fix the comparison to guard against atime<mtime. Fixes: 9b9c5bea0b96 ("cifs: do not return atime less than mtime") Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Cc: stfrench@microsoft.com Cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-27CIFS: fix a white space issue in cifs_get_inode_info()Dan Carpenter via samba-technical
We accidentally messed up the indenting on this if statement. Fixes: 16c696a6c300 ("CIFS: refactor cifs_get_inode_info()") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25CIFS: refactor cifs_get_inode_info()Aurelien Aptel
Make logic of cifs_get_inode() much clearer by moving code to sub functions and adding comments. Document the steps this function does. cifs_get_inode_info() gets and updates a file inode metadata from its file path. * If caller already has raw info data from server they can pass it. * If inode already exists (just need to update) caller can pass it. Step 1: get raw data from server if none was passed Step 2: parse raw data into intermediate internal cifs_fattr struct Step 3: set fattr uniqueid which is later used for inode number. This can sometime be done from raw data Step 4: tweak fattr according to mount options (file_mode, acl to mode bits, uid, gid, etc) Step 5: update or create inode from final fattr struct * add is_smb1_server() helper * add is_inode_cache_good() helper * move SMB1-backupcreds-getinfo-retry to separate func cifs_backup_query_path_info(). * move set-uniqueid code to separate func cifs_set_fattr_ino() * don't clobber uniqueid from backup cred retry * fix some probable corner cases memleaks Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-20cifs: Fix missed free operationsChuhong Yuan
cifs_setattr_nounix has two paths which miss free operations for xid and fullpath. Use goto cifs_setattr_exit like other paths to fix them. CC: Stable <stable@vger.kernel.org> Fixes: aa081859b10c ("cifs: flush before set-info if we have writeable handles") Signed-off-by: Chuhong Yuan <hslester96@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-10-09CIFS: Force revalidate inode when dentry is stalePavel Shilovsky
Currently the client indicates that a dentry is stale when inode numbers or type types between a local inode and a remote file don't match. If this is the case attributes is not being copied from remote to local, so, it is already known that the local copy has stale metadata. That's why the inode needs to be marked for revalidation in order to tell the VFS to lookup the dentry again before openning a file. This prevents unexpected stale errors to be returned to the user space when openning a file. Cc: <stable@vger.kernel.org> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-26smb3: pass mode bits into create callsSteve French
We need to populate an ACL (security descriptor open context) on file and directory correct. This patch passes in the mode. Followon patch will build the open context and the security descriptor (from the mode) that goes in the open context. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2019-09-16cifs: allow chmod to set mode bits using special sidSteve French
When mounting with "modefromsid" set mode bits (chmod) by adding ACE with special SID (S-1-5-88-3-<mode>) to the ACL. Subsequent patch will fix setting default mode on file create and mkdir. See See e.g. https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/hh509017(v=ws.10) Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-16cifs: get mode bits from special sid on statSteve French
When mounting with "modefromsid" retrieve mode bits from special SID (S-1-5-88-3) on stat. Subsequent patch will fix setattr (chmod) to save mode bits in S-1-5-88-3-<mode> Note that when an ACE matching S-1-5-88-3 is not found, we default the mode to an approximation based on the owner, group and everyone permissions (as with the "cifsacl" mount option). See See e.g. https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/hh509017(v=ws.10) Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-18cifs: flush before set-info if we have writeable handlesRonnie Sahlberg
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 <stable@vger.kernel.org> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07cifs: fix typo in debug message with struct field ia_validColin Ian King
Field ia_valid is being debugged with the field name iavalid, fix this. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07cifs: simplify code by removing CONFIG_CIFS_ACL ifdefSteve French
SMB3 ACL support is needed for many use cases now and should not be ifdeffed out, even for SMB1 (CIFS). Remove the CONFIG_CIFS_ACL ifdef so ACL support is always built into cifs.ko Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07cifs: add fiemap supportRonnie Sahlberg
Useful for improved copy performance as well as for applications which query allocated ranges of sparse files. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-04-24cifs: do not attempt cifs operation on smb2+ rename errorFrank Sorenson
A path-based rename returning EBUSY will incorrectly try opening the file with a cifs (NT Create AndX) operation on an smb2+ mount, which causes the server to force a session close. If the mount is smb2+, skip the fallback. Signed-off-by: Frank Sorenson <sorenson@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-04smb3: make default i/o size for smb3 mounts largerSteve French
We negotiate rsize mounts (and it can be overridden by user) to typically 4MB, so using larger default I/O sizes from userspace (changing to 1MB default i/o size returned by stat) the performance is much better (and not just for long latency network connections) in most use cases for SMB3 than the default I/O size (which ends up being 128K for cp and can be even smaller for cp). This can be 4x slower or worse depending on network latency. By changing inode->blocksize from 32K (which was perhaps ok for very old SMB1/CIFS) to a larger value, 1MB (but still less than max size negotiated with the server which is 4MB, in order to minimize risk) it significantly increases performance for the noncached case, and slightly increases it for the cached case. This can be changed by the user on mount (specifying bsize= values from 16K to 16MB) to tune better for performance for applications that depend on blocksize. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> CC: Stable <stable@vger.kernel.org>
2019-01-11CIFS: Fix error paths in writeback codePavel Shilovsky
This patch aims to address writeback code problems related to error paths. In particular it respects EINTR and related error codes and stores and returns the first error occurred during writeback. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-23cifs: auto disable 'serverino' in dfs mountsAurelien Aptel
Different servers have different set of file ids. After failover, unique IDs will be different so we can't validate them. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Paulo Alcantara <palcantara@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-23cifs: address trivial coverity warningSteve French
This is not actually a bug but as Coverity points out we shouldn't be doing an "|=" on a value which hasn't been set (although technically it was memset to zero so isn't a bug) and so might as well change "|=" to "=" in this line Detected by CoverityScan, CID#728535 ("Unitialized scalar variable") Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-11-02cifs: fix spelling mistake, EACCESS -> EACCESColin Ian King
Trivial fix to a spelling mistake of the error access name EACCESS, rename to EACCES Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23cifs: fallback to older infolevels on findfirst queryinfo retrySteve French
In cases where queryinfo fails, we have cases in cifs (vers=1.0) where with backupuid mounts we retry the query info with findfirst. This doesn't work to some NetApp servers which don't support WindowsXP (and later) infolevel 261 (SMB_FIND_FILE_ID_FULL_DIR_INFO) so in this case use other info levels (in this case it will usually be level 257, SMB_FIND_FILE_DIRECTORY_INFO). (Also fixes some indentation) See kernel bugzilla 201435 Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23smb3: do not attempt cifs operation in smb3 query info error pathSteve French
If backupuid mount option is sent, we can incorrectly retry (on access denied on query info) with a cifs (FindFirst) operation on an smb3 mount which causes the server to force the session close. We set backup intent on open so no need for this fallback. See kernel bugzilla 201435 Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-10-23cifs: do not return atime less than mtimeSteve French
In network file system it is fairly easy for server and client atime vs. mtime to get confused (and atime updated less frequently) which we noticed broke some apps which expect atime >= mtime Also ignore relatime mount option (rather than error on it) since relatime is basically what some network server fs are doing (relatime). Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-09-02SMB3: Backup intent flag missing for directory opens with backupuid mountsSteve French
When "backup intent" is requested on the mount (e.g. backupuid or backupgid mount options), the corresponding flag needs to be set on opens of directories (and files) but was missing in some places causing access denied trying to enumerate and backup servers. Fixes kernel bugzilla #200953 https://bugzilla.kernel.org/show_bug.cgi?id=200953 Reported-and-tested-by: <whh@rubrik.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-07smb3: Do not send SMB3 SET_INFO if nothing changedSteve French
An earlier commit had a typo which prevented the optimization from working: commit 18dd8e1a65dd ("Do not send SMB3 SET_INFO request if nothing is changing") Thank you to Metze for noticing this. Also clear a reserved field in the FILE_BASIC_INFO struct we send that should be zero (all the other fields in that struct were set or cleared explicitly already in cifs_set_file_info). Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> CC: Stable <stable@vger.kernel.org> # 4.9.x+ Reported-by: Stefan Metzmacher <metze@samba.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-08-07smb3: simplify code by removing CONFIG_CIFS_SMB311Steve French
We really, really want to be encouraging use of secure dialects, and SMB3.1.1 offers useful security features, and will soon be the recommended dialect for many use cases. Simplify the code by removing the CONFIG_CIFS_SMB311 ifdef so users don't disable it in the build, and create compatibility and/or security issues with modern servers - many of which have been supporting this dialect for multiple years. Also clarify some of the Kconfig text for cifs.ko about SMB3.1.1 and current supported features in the module. Signed-off-by: Steve French <stfrench@microsoft.com> Acked-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-08-07cifs: use timespec64 internallyArnd Bergmann
In cifs, the timestamps are stored in memory in the cifs_fattr structure, which uses the deprecated 'timespec' structure. Now that the VFS code has moved on to 'timespec64', the next step is to change over the fattr as well. This also makes 32-bit and 64-bit systems behave the same way, and no longer overflow the 32-bit time_t in year 2038. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Paulo Alcantara <palcantara@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-15smb3: Fix mode on mkdir on smb311 mountsSteve French
mkdir was not passing the mode on smb3.11 mounts with posix extensions Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-15Merge tag 'vfs-timespec64' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground Pull inode timestamps conversion to timespec64 from Arnd Bergmann: "This is a late set of changes from Deepa Dinamani doing an automated treewide conversion of the inode and iattr structures from 'timespec' to 'timespec64', to push the conversion from the VFS layer into the individual file systems. As Deepa writes: 'The series aims to switch vfs timestamps to use struct timespec64. Currently vfs uses struct timespec, which is not y2038 safe. The series involves the following: 1. Add vfs helper functions for supporting struct timepec64 timestamps. 2. Cast prints of vfs timestamps to avoid warnings after the switch. 3. Simplify code using vfs timestamps so that the actual replacement becomes easy. 4. Convert vfs timestamps to use struct timespec64 using a script. This is a flag day patch. Next steps: 1. Convert APIs that can handle timespec64, instead of converting timestamps at the boundaries. 2. Update internal data structures to avoid timestamp conversions' Thomas Gleixner adds: 'I think there is no point to drag that out for the next merge window. The whole thing needs to be done in one go for the core changes which means that you're going to play that catchup game forever. Let's get over with it towards the end of the merge window'" * tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground: pstore: Remove bogus format string definition vfs: change inode times to use struct timespec64 pstore: Convert internal records to timespec64 udf: Simplify calls to udf_disk_stamp_to_time fs: nfs: get rid of memcpys for inode times ceph: make inode time prints to be long long lustre: Use long long type to print inode time fs: add timespec64_truncate()
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-05vfs: change inode times to use struct timespec64Deepa Dinamani
struct timespec is not y2038 safe. Transition vfs to use y2038 safe struct timespec64 instead. The change was made with the help of the following cocinelle script. This catches about 80% of the changes. All the header file and logic changes are included in the first 5 rules. The rest are trivial substitutions. I avoid changing any of the function signatures or any other filesystem specific data structures to keep the patch simple for review. The script can be a little shorter by combining different cases. But, this version was sufficient for my usecase. virtual patch @ depends on patch @ identifier now; @@ - struct timespec + struct timespec64 current_time ( ... ) { - struct timespec now = current_kernel_time(); + struct timespec64 now = current_kernel_time64(); ... - return timespec_trunc( + return timespec64_trunc( ... ); } @ depends on patch @ identifier xtime; @@ struct \( iattr \| inode \| kstat \) { ... - struct timespec xtime; + struct timespec64 xtime; ... } @ depends on patch @ identifier t; @@ struct inode_operations { ... int (*update_time) (..., - struct timespec t, + struct timespec64 t, ...); ... } @ depends on patch @ identifier t; identifier fn_update_time =~ "update_time$"; @@ fn_update_time (..., - struct timespec *t, + struct timespec64 *t, ...) { ... } @ depends on patch @ identifier t; @@ lease_get_mtime( ... , - struct timespec *t + struct timespec64 *t ) { ... } @te depends on patch forall@ identifier ts; local idexpression struct inode *inode_node; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn_update_time =~ "update_time$"; identifier fn; expression e, E3; local idexpression struct inode *node1; local idexpression struct inode *node2; local idexpression struct iattr *attr1; local idexpression struct iattr *attr2; local idexpression struct iattr attr; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; @@ ( ( - struct timespec ts; + struct timespec64 ts; | - struct timespec ts = current_time(inode_node); + struct timespec64 ts = current_time(inode_node); ) <+... when != ts ( - timespec_equal(&inode_node->i_xtime, &ts) + timespec64_equal(&inode_node->i_xtime, &ts) | - timespec_equal(&ts, &inode_node->i_xtime) + timespec64_equal(&ts, &inode_node->i_xtime) | - timespec_compare(&inode_node->i_xtime, &ts) + timespec64_compare(&inode_node->i_xtime, &ts) | - timespec_compare(&ts, &inode_node->i_xtime) + timespec64_compare(&ts, &inode_node->i_xtime) | ts = current_time(e) | fn_update_time(..., &ts,...) | inode_node->i_xtime = ts | node1->i_xtime = ts | ts = inode_node->i_xtime | <+... attr1->ia_xtime ...+> = ts | ts = attr1->ia_xtime | ts.tv_sec | ts.tv_nsec | btrfs_set_stack_timespec_sec(..., ts.tv_sec) | btrfs_set_stack_timespec_nsec(..., ts.tv_nsec) | - ts = timespec64_to_timespec( + ts = ... -) | - ts = ktime_to_timespec( + ts = ktime_to_timespec64( ...) | - ts = E3 + ts = timespec_to_timespec64(E3) | - ktime_get_real_ts(&ts) + ktime_get_real_ts64(&ts) | fn(..., - ts + timespec64_to_timespec(ts) ,...) ) ...+> ( <... when != ts - return ts; + return timespec64_to_timespec(ts); ...> ) | - timespec_equal(&node1->i_xtime1, &node2->i_xtime2) + timespec64_equal(&node1->i_xtime2, &node2->i_xtime2) | - timespec_equal(&node1->i_xtime1, &attr2->ia_xtime2) + timespec64_equal(&node1->i_xtime2, &attr2->ia_xtime2) | - timespec_compare(&node1->i_xtime1, &node2->i_xtime2) + timespec64_compare(&node1->i_xtime1, &node2->i_xtime2) | node1->i_xtime1 = - timespec_trunc(attr1->ia_xtime1, + timespec64_trunc(attr1->ia_xtime1, ...) | - attr1->ia_xtime1 = timespec_trunc(attr2->ia_xtime2, + attr1->ia_xtime1 = timespec64_trunc(attr2->ia_xtime2, ...) | - ktime_get_real_ts(&attr1->ia_xtime1) + ktime_get_real_ts64(&attr1->ia_xtime1) | - ktime_get_real_ts(&attr.ia_xtime1) + ktime_get_real_ts64(&attr.ia_xtime1) ) @ depends on patch @ struct inode *node; struct iattr *attr; identifier fn; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; expression e; @@ ( - fn(node->i_xtime); + fn(timespec64_to_timespec(node->i_xtime)); | fn(..., - node->i_xtime); + timespec64_to_timespec(node->i_xtime)); | - e = fn(attr->ia_xtime); + e = fn(timespec64_to_timespec(attr->ia_xtime)); ) @ depends on patch forall @ struct inode *node; struct iattr *attr; identifier i_xtime =~ "^i_[acm]time$"; identifier ia_xtime =~ "^ia_[acm]time$"; identifier fn; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); fn (..., - &attr->ia_xtime, + &ts, ...); ) ...+> } @ depends on patch forall @ struct inode *node; struct iattr *attr; struct kstat *stat; identifier ia_xtime =~ "^ia_[acm]time$"; identifier i_xtime =~ "^i_[acm]time$"; identifier xtime =~ "^[acm]time$"; identifier fn, ret; @@ { + struct timespec ts; <+... ( + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime, + &ts, ...); | + ts = timespec64_to_timespec(node->i_xtime); ret = fn (..., - &node->i_xtime); + &ts); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime, + &ts, ...); | + ts = timespec64_to_timespec(attr->ia_xtime); ret = fn (..., - &attr->ia_xtime); + &ts); | + ts = timespec64_to_timespec(stat->xtime); ret = fn (..., - &stat->xtime); + &ts); ) ...+> } @ depends on patch @ struct inode *node; struct inode *node2; identifier i_xtime1 =~ "^i_[acm]time$"; identifier i_xtime2 =~ "^i_[acm]time$"; identifier i_xtime3 =~ "^i_[acm]time$"; struct iattr *attrp; struct iattr *attrp2; struct iattr attr ; identifier ia_xtime1 =~ "^ia_[acm]time$"; identifier ia_xtime2 =~ "^ia_[acm]time$"; struct kstat *stat; struct kstat stat1; struct timespec64 ts; identifier xtime =~ "^[acmb]time$"; expression e; @@ ( ( node->i_xtime2 \| attrp->ia_xtime2 \| attr.ia_xtime2 \) = node->i_xtime1 ; | node->i_xtime2 = \( node2->i_xtime1 \| timespec64_trunc(...) \); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \); | stat->xtime = node2->i_xtime1; | stat1.xtime = node2->i_xtime1; | ( node->i_xtime2 \| attrp->ia_xtime2 \) = attrp->ia_xtime1 ; | ( attrp->ia_xtime1 \| attr.ia_xtime1 \) = attrp2->ia_xtime2; | - e = node->i_xtime1; + e = timespec64_to_timespec( node->i_xtime1 ); | - e = attrp->ia_xtime1; + e = timespec64_to_timespec( attrp->ia_xtime1 ); | node->i_xtime1 = current_time(...); | node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | node->i_xtime1 = node->i_xtime3 = - e; + timespec_to_timespec64(e); | - node->i_xtime1 = e; + node->i_xtime1 = timespec_to_timespec64(e); ) Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Cc: <anton@tuxera.com> Cc: <balbi@kernel.org> Cc: <bfields@fieldses.org> Cc: <darrick.wong@oracle.com> Cc: <dhowells@redhat.com> Cc: <dsterba@suse.com> Cc: <dwmw2@infradead.org> Cc: <hch@lst.de> Cc: <hirofumi@mail.parknet.co.jp> Cc: <hubcap@omnibond.com> Cc: <jack@suse.com> Cc: <jaegeuk@kernel.org> Cc: <jaharkes@cs.cmu.edu> Cc: <jslaby@suse.com> Cc: <keescook@chromium.org> Cc: <mark@fasheh.com> Cc: <miklos@szeredi.hu> Cc: <nico@linaro.org> Cc: <reiserfs-devel@vger.kernel.org> Cc: <richard@nod.at> Cc: <sage@redhat.com> Cc: <sfrench@samba.org> Cc: <swhiteho@redhat.com> Cc: <tj@kernel.org> Cc: <trond.myklebust@primarydata.com> Cc: <tytso@mit.edu> Cc: <viro@zeniv.linux.org.uk>
2018-05-30cifs: invalidate cache when we truncate a fileRonnie Sahlberg
RHBZ: 1566345 When truncating a file we always do this synchronously to the server. Thus we need to make sure that the cached inode metadata is marked as stale so that on next getattr we will refresh the metadata. In this particular bug we want to ensure that both ctime and mtime are updated and become visible to the application after a truncate. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reported-by: Xiaoli Feng <xifeng@redhat.com>
2018-04-11cifs: Use ULL suffix for 64-bit constantGeert Uytterhoeven
On 32-bit (e.g. with m68k-linux-gnu-gcc-4.1): fs/cifs/inode.c: In function ‘simple_hashstr’: fs/cifs/inode.c:713: warning: integer constant is too large for ‘long’ type Fixes: 7ea884c77e5c97f1 ("smb3: Fix root directory when server returns inode number of zero") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-04-02smb3: Fix root directory when server returns inode number of zeroSteve French
Some servers return inode number zero for the root directory, which causes ls to display incorrect data (missing "." and ".."). If the server returns zero for the inode number of the root directory, fake an inode number for it. Signed-off-by: Steve French <smfrench@gmail.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> CC: Stable <stable@vger.kernel.org>
2018-04-01fs: cifs: Replace _free_xid call in cifs_root_iget functionPhillip Potter
Modify end of cifs_root_iget function in fs/cifs/inode.c to call free_xid(xid) instead of _free_xid(xid), thereby allowing debug notification of this action when enabled. Signed-off-by: Phillip Potter <phil@philpotter.co.uk> Signed-off-by: Steve French <smfrench@gmail.com>
2018-01-26CIFS: make IPC a regular tconAurelien Aptel
* Remove ses->ipc_tid. * Make IPC$ regular tcon. * Add a direct pointer to it in ses->tcon_ipc. * Distinguish PIPE tcon from IPC tcon by adding a tcon->pipe flag. All IPC tcons are pipes but not all pipes are IPC. * All TreeConnect functions now cannot take a NULL tcon object. The IPC tcon has the same lifetime as the session it belongs to. It is created when the session is created and destroyed when the session is destroyed. Since no mounts directly refer to the IPC tcon, its refcount should always be set to initialisation value (1). Thus we make sure cifs_put_tcon() skips it. If the mount request resulting in a new session being created requires encryption, try to require it too for IPC. * set SERVER_NAME_LENGTH to serverName actual size The maximum length of