lwn.git/fs/cifs/smb2ops.c, branch docs-6.0

netfs: Fix gcc-12 warning by embedding vfs inode in netfs_i_context

2022-06-09T20:55:00+00:00

While randstruct was satisfied with using an open-coded "void *" offset cast for the netfs_i_context <-> inode casting, __builtin_object_size() as used by FORTIFY_SOURCE was not as easily fooled. This was causing the following complaint[1] from gcc v12: In file included from include/linux/string.h:253, from include/linux/ceph/ceph_debug.h:7, from fs/ceph/inode.c:2: In function 'fortify_memset_chk', inlined from 'netfs_i_context_init' at include/linux/netfs.h:326:2, inlined from 'ceph_alloc_inode' at fs/ceph/inode.c:463:2: include/linux/fortify-string.h:242:25: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning] 242 | __write_overflow_field(p_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by embedding a struct inode into struct netfs_i_context (which should perhaps be renamed to struct netfs_inode). The struct inode vfs_inode fields are then removed from the 9p, afs, ceph and cifs inode structs and vfs_inode is then simply changed to "netfs.inode" in those filesystems. Further, rename netfs_i_context to netfs_inode, get rid of the netfs_inode() function that converted a netfs_i_context pointer to an inode pointer (that can now be done with &ctx->inode) and rename the netfs_i_context() function to netfs_inode() (which is now a wrapper around container_of()). Most of the changes were done with: perl -p -i -e 's/vfs_inode/netfs.inode/'g \ `git grep -l 'vfs_inode' -- fs/{9p,afs,ceph,cifs}/*.[ch]` Kees suggested doing it with a pair structure[2] and a special declarator to insert that into the network filesystem's inode wrapper[3], but I think it's cleaner to embed it - and then it doesn't matter if struct randomisation reorders things. Dave Chinner suggested using a filesystem-specific VFS_I() function in each filesystem to convert that filesystem's own inode wrapper struct into the VFS inode struct[4]. Version #2: - Fix a couple of missed name changes due to a disabled cifs option. - Rename nfs_i_context to nfs_inode - Use "netfs" instead of "nic" as the member name in per-fs inode wrapper structs. [ This also undoes commit 507160f46c55 ("netfs: gcc-12: temporarily disable '-Wattribute-warning' for now") that is no longer needed ] Fixes: bc899ee1c898 ("netfs: Add a netfs inode context") Reported-by: Jeff Layton Signed-off-by: David Howells Reviewed-by: Jeff Layton Reviewed-by: Kees Cook Reviewed-by: Xiubo Li cc: Jonathan Corbet cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Dominique Martinet cc: Christian Schoenebeck cc: Marc Dionne cc: Ilya Dryomov cc: Steve French cc: William Kucharski cc: "Matthew Wilcox (Oracle)" cc: Dave Chinner cc: linux-doc@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: samba-technical@lists.samba.org cc: linux-fsdevel@vger.kernel.org cc: linux-hardening@vger.kernel.org Link: https://lore.kernel.org/r/d2ad3a3d7bdd794c6efb562d2f2b655fb67756b9.camel@kernel.org/ [1] Link: https://lore.kernel.org/r/20220517210230.864239-1-keescook@chromium.org/ [2] Link: https://lore.kernel.org/r/20220518202212.2322058-1-keescook@chromium.org/ [3] Link: https://lore.kernel.org/r/20220524101205.GI2306852@dread.disaster.area/ [4] Link: https://lore.kernel.org/r/165296786831.3591209.12111293034669289733.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/165305805651.4094995.7763502506786714216.stgit@warthog.procyon.org.uk # v2 Signed-off-by: Linus Torvalds

cifs: version operations for smb20 unneeded when legacy support disabled

2022-06-02T03:30:36+00:00

We should not be including unused smb20 specific code when legacy support is disabled (CONFIG_CIFS_ALLOW_INSECURE_LEGACY turned off). For example smb2_operations and smb2_values aren't used in that case. Over time we can move more and more SMB1/CIFS and SMB2.0 code into the insecure legacy ifdefs Reviewed-by: Ronnie Sahlberg Signed-off-by: Steve French

cifs: when extending a file with falloc we should make files not-sparse

2022-05-31T23:04:06+00:00

as this is the only way to make sure the region is allocated. Fix the conditional that was wrong and only tried to make already non-sparse files non-sparse. Cc: stable@vger.kernel.org Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French

smb3: remove unneeded null check in cifs_readdir

2022-05-27T17:05:47+00:00

Coverity pointed out an unneeded check. Addresses-Coverity: 1518030 ("Null pointer dereferences") Reviewed-by: Ronnie Sahlberg Signed-off-by: Steve French

cifs: cache the dirents for entries in a cached directory

2022-05-24T19:33:11+00:00

This adds caching of the directory entries for a cached directory while we keep a lease on the directory. Reviewed-by: Paulo Alcantara (SUSE) Reviewed-by: Enzo Matsumiya Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French

smb3: don't set rc when used and unneeded in query_info_compound

2022-05-24T02:02:45+00:00

rc is not checked so should not be set coming back from open_cached_dir (the cfid pointer is checked instead to see if open_cached_dir failed) Addresses-Coverity: 1518021 ("Code maintainability issues (UNUSED_VALUE)") Reviewed-by: Ronnie Sahlberg Signed-off-by: Steve French

smb3: check for null tcon

2022-05-24T01:50:38+00:00

Although unlikely to be null, it is confusing to use a pointer before checking for it to be null so move the use down after null check. Addresses-Coverity: 1517586 ("Null pointer dereferences (REVERSE_INULL)") Reviewed-by: Ronnie Sahlberg Signed-off-by: Steve French

cifs: set the CREATE_NOT_FILE when opening the directory in use_cached_dir()

2022-05-21T17:23:24+00:00

This enforces that we can only do this for directories and not normal files or else the server will return an error. This means that we will have conditionally check IF the path refers to a directory or not in all the call-sites where we are unsure. Right now this check is for "" i.e. root. Reviewed-by: Paulo Alcantara (SUSE) Reviewed-by: Enzo Matsumiya Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French

cifs: check for smb1 in open_cached_dir()

2022-05-21T17:23:08+00:00

Check protocol version in open_cached_dir() and return not supported for SMB1. This allows us to call open_cached_dir() from code that is common to both smb1 and smb2/3 in future patches without having to do this check in the call-site. At the same time, add a check if tcon is valid or not for the same reason. Reviewed-by: Paulo Alcantara (SUSE) Reviewed-by: Enzo Matsumiya Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French

cifs: destage any unwritten data to the server before calling copychunk_write

2022-04-21T03:54:54+00:00

because the copychunk_write might cover a region of the file that has not yet been sent to the server and thus fail. A simple way to reproduce this is: truncate -s 0 /mnt/testfile; strace -f -o x -ttT xfs_io -i -f -c 'pwrite 0k 128k' -c 'fcollapse 16k 24k' /mnt/testfile the issue is that the 'pwrite 0k 128k' becomes rearranged on the wire with the 'fcollapse 16k 24k' due to write-back caching. fcollapse is implemented in cifs.ko as a SMB2 IOCTL(COPYCHUNK_WRITE) call and it will fail serverside since the file is still 0b in size serverside until the writes have been destaged. To avoid this we must ensure that we destage any unwritten data to the server before calling COPYCHUNK_WRITE. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1997373 Reported-by: Xiaoli Feng Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French