22 Commits

Author SHA1 Message Date
Amir Goldstein
e1a4f5880d vfs: fix copy_file_range() averts filesystem freeze protection
commit 10bc8e4af65946b727728d7479c028742321b60a upstream.

Commit 868f9f2f8e00 ("vfs: fix copy_file_range() regression in cross-fs
copies") removed fallback to generic_copy_file_range() for cross-fs
cases inside vfs_copy_file_range().

To preserve behavior of nfsd and ksmbd server-side-copy, the fallback to
generic_copy_file_range() was added in nfsd and ksmbd code, but that
call is missing sb_start_write(), fsnotify hooks and more.

Ideally, nfsd and ksmbd would pass a flag to vfs_copy_file_range() that
will take care of the fallback, but that code would be subtle and we got
vfs_copy_file_range() logic wrong too many times already.

Instead, add a flag to explicitly request vfs_copy_file_range() to
perform only generic_copy_file_range() and let nfsd and ksmbd use this
flag only in the fallback path.

This choise keeps the logic changes to minimum in the non-nfsd/ksmbd code
paths to reduce the risk of further regressions.

Fixes: 868f9f2f8e00 ("vfs: fix copy_file_range() regression in cross-fs copies")
Tested-by: Namjae Jeon <linkinjeon@kernel.org>
Tested-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[backport comments for v5.15: - sb_write_started() is missing - assert was dropped ]
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-19 12:36:39 +01:00
Namjae Jeon
cb69d4d6f7 ksmbd: fix heap-based overflow in set_ntacl_dacl()
commit 8f0541186e9ad1b62accc9519cc2b7a7240272a7 upstream.

The testcase use SMB2_SET_INFO_HE command to set a malformed file attribute
under the label `security.NTACL`. SMB2_QUERY_INFO_HE command in testcase
trigger the following overflow.

[ 4712.003781] ==================================================================
[ 4712.003790] BUG: KASAN: slab-out-of-bounds in build_sec_desc+0x842/0x1dd0 [ksmbd]
[ 4712.003807] Write of size 1060 at addr ffff88801e34c068 by task kworker/0:0/4190

[ 4712.003813] CPU: 0 PID: 4190 Comm: kworker/0:0 Not tainted 5.19.0-rc5 #1
[ 4712.003850] Workqueue: ksmbd-io handle_ksmbd_work [ksmbd]
[ 4712.003867] Call Trace:
[ 4712.003870]  <TASK>
[ 4712.003873]  dump_stack_lvl+0x49/0x5f
[ 4712.003935]  print_report.cold+0x5e/0x5cf
[ 4712.003972]  ? ksmbd_vfs_get_sd_xattr+0x16d/0x500 [ksmbd]
[ 4712.003984]  ? cmp_map_id+0x200/0x200
[ 4712.003988]  ? build_sec_desc+0x842/0x1dd0 [ksmbd]
[ 4712.004000]  kasan_report+0xaa/0x120
[ 4712.004045]  ? build_sec_desc+0x842/0x1dd0 [ksmbd]
[ 4712.004056]  kasan_check_range+0x100/0x1e0
[ 4712.004060]  memcpy+0x3c/0x60
[ 4712.004064]  build_sec_desc+0x842/0x1dd0 [ksmbd]
[ 4712.004076]  ? parse_sec_desc+0x580/0x580 [ksmbd]
[ 4712.004088]  ? ksmbd_acls_fattr+0x281/0x410 [ksmbd]
[ 4712.004099]  smb2_query_info+0xa8f/0x6110 [ksmbd]
[ 4712.004111]  ? psi_group_change+0x856/0xd70
[ 4712.004148]  ? update_load_avg+0x1c3/0x1af0
[ 4712.004152]  ? asym_cpu_capacity_scan+0x5d0/0x5d0
[ 4712.004157]  ? xas_load+0x23/0x300
[ 4712.004162]  ? smb2_query_dir+0x1530/0x1530 [ksmbd]
[ 4712.004173]  ? _raw_spin_lock_bh+0xe0/0xe0
[ 4712.004179]  handle_ksmbd_work+0x30e/0x1020 [ksmbd]
[ 4712.004192]  process_one_work+0x778/0x11c0
[ 4712.004227]  ? _raw_spin_lock_irq+0x8e/0xe0
[ 4712.004231]  worker_thread+0x544/0x1180
[ 4712.004234]  ? __cpuidle_text_end+0x4/0x4
[ 4712.004239]  kthread+0x282/0x320
[ 4712.004243]  ? process_one_work+0x11c0/0x11c0
[ 4712.004246]  ? kthread_complete_and_exit+0x30/0x30
[ 4712.004282]  ret_from_fork+0x1f/0x30

This patch add the buffer validation for security descriptor that is
stored by malformed SMB2_SET_INFO_HE command. and allocate large
response buffer about SMB2_O_INFO_SECURITY file info class.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-17771
Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21 15:17:48 +02:00
Amir Goldstein
4d5055873e vfs: fix copy_file_range() regression in cross-fs copies
commit 868f9f2f8e004bfe0d3935b1976f625b2924893b upstream.

A regression has been reported by Nicolas Boichat, found while using the
copy_file_range syscall to copy a tracefs file.

Before commit 5dae222a5ff0 ("vfs: allow copy_file_range to copy across
devices") the kernel would return -EXDEV to userspace when trying to
copy a file across different filesystems.  After this commit, the
syscall doesn't fail anymore and instead returns zero (zero bytes
copied), as this file's content is generated on-the-fly and thus reports
a size of zero.

Another regression has been reported by He Zhe - the assertion of
WARN_ON_ONCE(ret == -EOPNOTSUPP) can be triggered from userspace when
copying from a sysfs file whose read operation may return -EOPNOTSUPP.

Since we do not have test coverage for copy_file_range() between any two
types of filesystems, the best way to avoid these sort of issues in the
future is for the kernel to be more picky about filesystems that are
allowed to do copy_file_range().

This patch restores some cross-filesystem copy restrictions that existed
prior to commit 5dae222a5ff0 ("vfs: allow copy_file_range to copy across
devices"), namely, cross-sb copy is not allowed for filesystems that do
not implement ->copy_file_range().

Filesystems that do implement ->copy_file_range() have full control of
the result - if this method returns an error, the error is returned to
the user.  Before this change this was only true for fs that did not
implement the ->remap_file_range() operation (i.e.  nfsv3).

Filesystems that do not implement ->copy_file_range() still fall-back to
the generic_copy_file_range() implementation when the copy is within the
same sb.  This helps the kernel can maintain a more consistent story
about which filesystems support copy_file_range().

nfsd and ksmbd servers are modified to fall-back to the
generic_copy_file_range() implementation in case vfs_copy_file_range()
fails with -EOPNOTSUPP or -EXDEV, which preserves behavior of
server-side-copy.

fall-back to generic_copy_file_range() is not implemented for the smb
operation FSCTL_DUPLICATE_EXTENTS_TO_FILE, which is arguably a correct
change of behavior.

Fixes: 5dae222a5ff0 ("vfs: allow copy_file_range to copy across devices")
Link: https://lore.kernel.org/linux-fsdevel/20210212044405.4120619-1-drinkcat@chromium.org/
Link: https://lore.kernel.org/linux-fsdevel/CANMq1KDZuxir2LM5jOTm0xx+BnvW=ZmpsG47CyHFJwnw7zSX6Q@mail.gmail.com/
Link: https://lore.kernel.org/linux-fsdevel/20210126135012.1.If45b7cdc3ff707bc1efa17f5366057d60603c45f@changeid/
Link: https://lore.kernel.org/linux-fsdevel/20210630161320.29006-1-lhenriques@suse.de/
Reported-by: Nicolas Boichat <drinkcat@chromium.org>
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Luis Henriques <lhenriques@suse.de>
Fixes: 64bf5ff58dff ("vfs: no fallback for ->copy_file_range")
Link: https://lore.kernel.org/linux-fsdevel/20f17f64-88cb-4e80-07c1-85cb96c83619@windriver.com/
Reported-by: He Zhe <zhe.he@windriver.com>
Tested-by: Namjae Jeon <linkinjeon@kernel.org>
Tested-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:27 +02:00
Jason A. Donenfeld
e33f5b5815 ksmbd: use vfs_llseek instead of dereferencing NULL
commit 067baa9a37b32b95fdeabccde4b0cb6a2cf95f96 upstream.

By not checking whether llseek is NULL, this might jump to NULL. Also,
it doesn't check FMODE_LSEEK. Fix this by using vfs_llseek(), which
always does the right thing.

Fixes: f44158485826 ("cifsd: add file operations")
Cc: stable@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: Ronnie Sahlberg <lsahlber@redhat.com>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:23 +02:00
Namjae Jeon
6791b57284 ksmbd: set the range of bytes to zero without extending file size in FSCTL_ZERO_DATA
commit 18e39fb960e6a908ac5230b57e3d0d6c25232368 upstream.

generic/091, 263 test failed since commit f66f8b94e7f2 ("cifs: when
extending a file with falloc we should make files not-sparse").
FSCTL_ZERO_DATA sets the range of bytes to zero without extending file
size. The VFS_FALLOCATE_FL_KEEP_SIZE flag should be used even on
non-sparse files.

Cc: stable@vger.kernel.org
Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:23 +02:00
Namjae Jeon
f7db8fd03a ksmbd: add validation in smb2_ioctl
Add validation for request/response buffer size check in smb2_ioctl and
fsctl_copychunk() take copychunk_ioctl_req pointer and the other arguments
instead of smb2_ioctl_req structure and remove an unused smb2_ioctl_req
argument of fsctl_validate_negotiate_info.

Cc: Tom Talpey <tom@talpey.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Böhme <slow@samba.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-10-13 23:37:18 -05:00
Hyunchul Lee
265fd1991c ksmbd: use LOOKUP_BENEATH to prevent the out of share access
instead of removing '..' in a given path, call
kern_path with LOOKUP_BENEATH flag to prevent
the out of share access.

ran various test on this:
smb2-cat-async smb://127.0.0.1/homes/../out_of_share
smb2-cat-async smb://127.0.0.1/homes/foo/../../out_of_share
smbclient //127.0.0.1/homes -c "mkdir ../foo2"
smbclient //127.0.0.1/homes -c "rename bar ../bar"

Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Boehme <slow@samba.org>
Tested-by: Steve French <smfrench@gmail.com>
Tested-by: Namjae Jeon <linkinjeon@kernel.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-24 21:25:23 -05:00
Namjae Jeon
4ea477988c ksmbd: remove follow symlinks support
Use  LOOKUP_NO_SYMLINKS flags for default lookup to prohibit the middle of
symlink component lookup and remove follow symlinks parameter support.
We re-implement it as reparse point later.

Test result:
smbclient -Ulinkinjeon%1234 //172.30.1.42/share -c
"get hacked/passwd passwd"
NT_STATUS_OBJECT_NAME_NOT_FOUND opening remote file \hacked\passwd

Cc: Ralph Böhme <slow@samba.org>
Cc: Steve French <smfrench@gmail.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-22 23:37:38 -05:00
Christian Brauner
0e844efebd ksmbd: fix translation in acl entries
The ksmbd server performs translation of posix acls to smb acls.
Currently the translation is wrong since the idmapping of the mount is
used to map the ids into raw userspace ids but what is relevant is the
user namespace of ksmbd itself. The user namespace of ksmbd itself which
is the initial user namespace. The operation is similar to asking "What
*ids would a userspace process see given that k*id in the relevant user
namespace?". Before the final translation we need to apply the idmapping
of the mount in case any is used. Add two simple helpers for ksmbd.

Cc: Steve French <stfrench@microsoft.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-03 23:29:44 -05:00
Christian Brauner
da1e7ada5b ksmbd: fix lookup on idmapped mounts
It's great that the new in-kernel ksmbd server will support idmapped
mounts out of the box! However, lookup is currently broken. Lookup
helpers such as lookup_one_len() call inode_permission() internally to
ensure that the caller is privileged over the inode of the base dentry
they are trying to lookup under. So the permission checking here is
currently wrong.

Linux v5.15 will gain a new lookup helper lookup_one() that does take
idmappings into account. I've added it as part of my patch series to
make btrfs support idmapped mounts. The new helper is in linux-next as
part of David's (Sterba) btrfs for-next branch as commit
c972214c133b ("namei: add mapping aware lookup helper").

I've said it before during one of my first reviews: I would very much
recommend adding fstests to [1]. It already seems to have very
rudimentary cifs support. There is a completely generic idmapped mount
testsuite that supports idmapped mounts.

[1]: https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git/
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Steve French <stfrench@microsoft.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: David Sterba <dsterba@suse.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-03 23:29:44 -05:00
Namjae Jeon
777cad1604 ksmbd: remove select FS_POSIX_ACL in Kconfig
ksmbd is forcing to turn on FS_POSIX_ACL in Kconfig to use vfs acl
functions(posix_acl_alloc, get_acl, set_posix_acl). OpenWRT and other
platform doesn't use acl and this config is disable by default in
kernel. This patch use IS_ENABLED() to know acl config is enable and use
acl function if it is enable.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-08-13 08:18:10 +09:00
Namjae Jeon
78ad2c277a ksmbd: fix memory leak in ksmbd_vfs_get_sd_xattr()
Add free acl.sd_buf and n.data on error handling in
ksmbd_vfs_get_sd_xattr().

Reported-by: Coverity Scan <scan-admin@coverity.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-13 17:22:47 +09:00
Hyunchul Lee
45a64e8b08 ksmbd: uninterruptible wait for a file being unlocked
the wait can be canceled by SMB2_CANCEL, SMB2_CLOSE,
SMB2_LOGOFF, disconnection or shutdown, we don't have
to use wait_event_interruptible.

And this remove the warning from Coverity:

CID 1502834 (#1 of 1): Unused value (UNUSED_VALUE)
returned_value: Assigning value from ksmbd_vfs_posix_lock_wait(flock)
to err here, but that stored value is overwritten before it can be used.

Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-10 16:23:56 +09:00
Dan Carpenter
07781de905 ksmbd: use kasprintf() in ksmbd_vfs_xattr_stream_name()
Simplify the code by using kasprintf().  This also silences a Smatch
warning:

    fs/ksmbd/vfs.c:1725 ksmbd_vfs_xattr_stream_name()
    warn: inconsistent indenting

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-10 09:29:13 +09:00
Hyunchul Lee
465d720485 ksmbd: call mnt_user_ns once in a function
Avoid calling mnt_user_ns() many time in
a function.

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christian Brauner <christian@brauner.io>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-05 09:22:49 +09:00
Hyunchul Lee
af34983e83 ksmbd: add user namespace support
For user namespace support, call vfs functions
with struct user_namespace got from struct path.

This patch have been tested mannually as below.

Create an id-mapped mount using the mount-idmapped utility
(https://github.com/brauner/mount-idmapped).
$ mount-idmapped --map-mount b:1003:1002:1 /home/foo <EXPORT DIR>/foo
(the user, "foo" is 1003, and the user "bar" is 1002).

And  mount the export directory using cifs with the user, "bar".
succeed to create/delete/stat/read/write files and directory in
the <EXPORT DIR>/foo. But fail with a bind mount for /home/foo.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-07-02 16:27:10 +09:00
Namjae Jeon
12202c0594 ksmbd: use ksmbd_vfs_lock_parent to get stable parent dentry
Use ksmbd_vfs_lock_parent to get stable parent dentry and remove
PARENT_INODE macro.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-29 15:07:51 +09:00
Namjae Jeon
ab0b263b74 ksmbd: opencode to remove FP_INODE macro
Opencode to remove FP_INODE macro.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-29 15:07:48 +09:00
Namjae Jeon
493fa2fbe4 ksmbd: fix dentry racy with rename()
Using ->d_name can be broken due to races with rename().
So use %pd with ->d_name to print filename and In other cases,
use it under ->d_lock.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-29 15:07:44 +09:00
Hyunchul Lee
6c5e36d13e ksmbd: set MAY_* flags together with open flags
set MAY_* flags together with open flags and
remove ksmbd_vfs_inode_permission().

Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-28 16:28:41 +09:00
Hyunchul Lee
333111a6dc ksmbd: factor out a ksmbd_vfs_lock_parent helper
Factor out a self-contained helper to
get stable parent dentry.

Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-28 16:28:37 +09:00
Namjae Jeon
1a93084b9a ksmbd: move fs/cifsd to fs/ksmbd
Move fs/cifsd to fs/ksmbd and rename the remaining cifsd name to ksmbd.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-28 16:28:31 +09:00