Commit Graph

67197 Commits

Author SHA1 Message Date
Tetsuhiro Kohada
d6c9efd924 exfat: fix pointer error checking
Fix missing result check of exfat_build_inode().
And use PTR_ERR_OR_ZERO instead of PTR_ERR.

Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2020-10-07 14:26:55 +09:00
Linus Torvalds
d1a819a2ec splice: teach splice pipe reading about empty pipe buffers
Tetsuo Handa reports that splice() can return 0 before the real EOF, if
the data in the splice source pipe is an empty pipe buffer.  That empty
pipe buffer case doesn't happen in any normal situation, but you can
trigger it by doing a write to a pipe that fails due to a page fault.

Tetsuo has a test-case to show the behavior:

  #define _GNU_SOURCE
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>
  #include <unistd.h>

  int main(int argc, char *argv[])
  {
	const int fd = open("/tmp/testfile", O_WRONLY | O_CREAT, 0600);
	int pipe_fd[2] = { -1, -1 };
	pipe(pipe_fd);
	write(pipe_fd[1], NULL, 4096);
	/* This splice() should wait unless interrupted. */
	return !splice(pipe_fd[0], NULL, fd, NULL, 65536, 0);
  }

which results in

    write(5, NULL, 4096)                    = -1 EFAULT (Bad address)
    splice(4, NULL, 3, NULL, 65536, 0)      = 0

and this can confuse splice() users into believing they have hit EOF
prematurely.

The issue was introduced when the pipe write code started pre-allocating
the pipe buffers before copying data from user space.

This is modified verion of Tetsuo's original patch.

Fixes: a194dfe6e6 ("pipe: Rearrange sequence in pipe_write() to preallocate slot")
Link:https://lore.kernel.org/linux-fsdevel/20201005121339.4063-1-penguin-kernel@I-love.SAKURA.ne.jp/
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-06 10:27:22 -07:00
Ashish Sangwan
247db73560 NFS: fix nfs_path in case of a rename retry
We are generating incorrect path in case of rename retry because
we are restarting from wrong dentry. We should restart from the
dentry which was received in the call to nfs_path.

CC: stable@vger.kernel.org
Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-10-06 10:21:18 -04:00
Amir Goldstein
be4df0cea0 ovl: use generic vfs_ioc_setflags_prepare() helper
Canonalize to ioctl FS_* flags instead of inode S_* flags.

Note that we do not call the helper vfs_ioc_fssetxattr_check()
for FS_IOC_FSSETXATTR ioctl. The reason is that underlying filesystem
will perform all the checks. We only need to perform the capability
check before overriding credentials.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-10-06 15:38:15 +02:00
Amir Goldstein
61536bed21 ovl: support [S|G]ETFLAGS and FS[S|G]ETXATTR ioctls for directories
[S|G]ETFLAGS and FS[S|G]ETXATTR ioctls are applicable to both files and
directories, so add ioctl operations to dir as well.

We teach ovl_real_fdget() to get the realfile of directories which use
a different type of file->private_data.

Ifdef away compat ioctl implementation to conform to standard practice.

With this change, xfstest generic/079 which tests these ioctls on files
and directories passes.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-10-06 15:38:14 +02:00
David S. Miller
8b0308fe31 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Rejecting non-native endian BTF overlapped with the addition
of support for it.

The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-05 18:40:01 -07:00
Christoph Hellwig
10ed16662d block: add a bdget_part helper
All remaining callers of bdget() outside of fs/block_dev.c want to get a
reference to the struct block_device for a given struct hd_struct.  Add
a helper just for that and then mark bdget static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-05 10:38:33 -06:00
Kees Cook
0fa8e08464 fs/kernel_file_read: Add "offset" arg for partial reads
To perform partial reads, callers of kernel_read_file*() must have a
non-NULL file_size argument and a preallocated buffer. The new "offset"
argument can then be used to seek to specific locations in the file to
fill the buffer to, at most, "buf_size" per call.

Where possible, the LSM hooks can report whether a full file has been
read or not so that the contents can be reasoned about.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20201002173828.2099543-14-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:04 +02:00
Kees Cook
2039bda1fa LSM: Add "contents" flag to kernel_read_file hook
As with the kernel_load_data LSM hook, add a "contents" flag to the
kernel_read_file LSM hook that indicates whether the LSM can expect
a matching call to the kernel_post_read_file LSM hook with the full
contents of the file. With the coming addition of partial file read
support for kernel_read_file*() API, the LSM will no longer be able
to always see the entire contents of a file during the read calls.

For cases where the LSM must read examine the complete file contents,
it will need to do so on its own every time the kernel_read_file
hook is called with contents=false (or reject such cases). Adjust all
existing LSMs to retain existing behavior.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-12-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook
885352881f fs/kernel_read_file: Add file_size output argument
In preparation for adding partial read support, add an optional output
argument to kernel_read_file*() that reports the file size so callers
can reason more easily about their reading progress.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-8-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:37:03 +02:00
Kees Cook
113eeb5177 fs/kernel_read_file: Switch buffer size arg to size_t
In preparation for further refactoring of kernel_read_file*(), rename
the "max_size" argument to the more accurate "buf_size", and correct
its type to size_t. Add kerndoc to explain the specifics of how the
arguments will be used. Note that with buf_size now size_t, it can no
longer be negative (and was never called with a negative value). Adjust
callers to use it as a "maximum size" when *buf is NULL.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-7-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:19 +02:00
Kees Cook
f7a4f689bc fs/kernel_read_file: Remove redundant size argument
In preparation for refactoring kernel_read_file*(), remove the redundant
"size" argument which is not needed: it can be included in the return
code, with callers adjusted. (VFS reads already cannot be larger than
INT_MAX.)

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-6-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Kees Cook
5287b07f6d fs/kernel_read_file: Split into separate source file
These routines are used in places outside of exec(2), so in preparation
for refactoring them, move them into a separate source file,
fs/kernel_read_file.c.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20201002173828.2099543-5-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Scott Branden
b89999d004 fs/kernel_read_file: Split into separate include file
Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h
include file. That header gets pulled in just about everywhere
and doesn't really need functions not related to the general fs interface.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com
Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Kees Cook
c307459b9d fs/kernel_read_file: Remove FIRMWARE_PREALLOC_BUFFER enum
FIRMWARE_PREALLOC_BUFFER is a "how", not a "what", and confuses the LSMs
that are interested in filtering between types of things. The "how"
should be an internal detail made uninteresting to the LSMs.

Fixes: a098ecd2fa ("firmware: support loading into a pre-allocated buffer")
Fixes: fd90bc559b ("ima: based on policy verify firmware signatures (pre-allocated buffer)")
Fixes: 4f0496d8ff ("ima: based on policy warn about loading firmware (pre-allocated buffer)")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201002173828.2099543-2-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05 13:34:18 +02:00
Christoph Hellwig
598b3cec83 fs: remove compat_sys_vmsplice
Now that import_iovec handles compat iovecs, the native vmsplice syscall
can be used for the compat case as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03 00:02:15 -04:00
Christoph Hellwig
5f764d624a fs: remove the compat readv/writev syscalls
Now that import_iovec handles compat iovecs, the native readv and writev
syscalls can be used for the compat case as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03 00:02:14 -04:00
Christoph Hellwig
3523a9d454 fs: remove various compat readv/writev helpers
Now that import_iovec handles compat iovecs as well, all the duplicated
code in the compat readv/writev helpers is not needed.  Remove them
and switch the compat syscall handlers to use the native helpers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03 00:02:14 -04:00
Christoph Hellwig
89cd35c58b iov_iter: transparently handle compat iovecs in import_iovec
Use in compat_syscall to import either native or the compat iovecs, and
remove the now superflous compat_import_iovec.

This removes the need for special compat logic in most callers, and
the remaining ones can still be simplified by using __import_iovec
with a bool compat parameter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03 00:02:13 -04:00
Jakub Kicinski
66a9b9287d genetlink: move to smaller ops wherever possible
Bulk of the genetlink users can use smaller ops, move them.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:11 -07:00
Linus Torvalds
702bfc891d Merge tag 'io_uring-5.9-2020-10-02' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:

 - fix for async buffered reads if read-ahead is fully disabled (Hao)

 - double poll match fix

 - ->show_fdinfo() potential ABBA deadlock complaint fix

* tag 'io_uring-5.9-2020-10-02' of git://git.kernel.dk/linux-block:
  io_uring: fix async buffered reads when readahead is disabled
  io_uring: fix potential ABBA deadlock in ->show_fdinfo()
  io_uring: always delete double poll wait entry on match
2020-10-02 14:38:10 -07:00
Linus Torvalds
d4fce2e20f Merge branch 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull epoll fixes from Al Viro:
 "Several race fixes in epoll"

* 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ep_create_wakeup_source(): dentry name can change under you...
  epoll: EPOLL_CTL_ADD: close the race in decision to take fast path
  epoll: replace ->visited/visited_list with generation count
  epoll: do not insert into poll queues until all sanity checks are done
2020-10-02 10:37:08 -07:00
Linus Torvalds
4e3b9ce271 Merge tag 'for-5.9-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
 "Two more fixes.

  One is for a lockdep warning/lockup (also caught by syzbot), that one
  has been seen in practice. Regarding the other syzbot reports
  mentioned last time, they don't seem to be urgent and reliably
  reproducible so they'll be fixed later.

  The second fix is for a potential corruption when device replace
  finishes and the in-memory state of trim is not copied to the new
  device"

* tag 'for-5.9-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix filesystem corruption after a device replace
  btrfs: move btrfs_rm_dev_replace_free_srcdev outside of all locks
  btrfs: move btrfs_scratch_superblocks into btrfs_dev_replace_finishing
2020-10-02 10:09:40 -07:00
Chuck Lever
4b74fd793a NFSD: Map nfserr_wrongsec outside of nfsd_dispatch
Refactor: Handle this NFS version-specific mapping in the only
place where nfserr_wrongsec is generated.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:42 -04:00
Chuck Lever
14168d678a NFSD: Remove the RETURN_STATUS() macro
Refactor: I'm about to change the return value from .pc_func. Clear
the way by replacing the RETURN_STATUS() macro with logic that
plants the status code directly into the response structure.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:42 -04:00
Chuck Lever
f0af22101d NFSD: Call NFSv2 encoders on error returns
Remove special dispatcher logic for NFSv2 error responses. These are
rare to the point of becoming extinct, but all NFS responses have to
pay the cost of the extra conditional branches.

With this change, the NFSv2 error cases now get proper
xdr_ressize_check() calls.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:42 -04:00
Chuck Lever
1841b9b614 NFSD: Fix .pc_release method for NFSv2
nfsd_release_fhandle() assumes that rqstp->rq_resp always points to
an nfsd_fhandle struct. In fact, no NFSv2 procedure uses struct
nfsd_fhandle as its response structure.

So far that has been "safe" to do because the res structs put the
resp->fh field at that same offset as struct nfsd_fhandle. I don't
think that's a guarantee, though, and there is certainly nothing
preventing a developer from altering the fields in those structures.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:42 -04:00
Chuck Lever
7cf8357043 NFSD: Remove vestigial typedefs
Clean up: These are not used.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:42 -04:00
Chuck Lever
85085aacef NFSD: Refactor nfsd_dispatch() error paths
nfsd_dispatch() is a hot path. Ensure the compiler takes the
processing of rare error cases out of line.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Chuck Lever
4c96cb56ee NFSD: Clean up nfsd_dispatch() variables
For consistency and code legibility, use a similar organization of
variables as svc_generic_dispatch().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Chuck Lever
383c440d4f NFSD: Clean up stale comments in nfsd_dispatch()
Add a documenting comment for the function. Remove comments that
simply describe obvious aspects of the code, but leave comments
that explain the differences in processing of each NFS version.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Chuck Lever
84c138e78d NFSD: Clean up switch statement in nfsd_dispatch()
Reorder the arms so the compiler places checks for the most frequent
case first.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Chuck Lever
dcc46991d3 NFSD: Encoder and decoder functions are always present
nfsd_dispatch() is a hot path. Let's optimize the XDR method calls
for the by-far common case, which is that the XDR methods are indeed
present.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Chuck Lever
ba1df797e5 NFSACL: Replace PROC() macro with open code
Clean up: Follow-up on ten-year-old commit b9081d90f5 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the NFSACL code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Chuck Lever
49d9960821 lockd: Replace PROC() macro with open code
Clean up: Follow-up on ten-year-old commit b9081d90f5 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the lockd code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Chuck Lever
6b3dccd48d NFSD: Add missing NFSv2 .pc_func methods
There's no protection in nfsd_dispatch() against a NULL .pc_func
helpers. A malicious NFS client can trigger a crash by invoking the
unused/unsupported NFSv2 ROOT or WRITECACHE procedures.

The current NFSD dispatcher does not support returning a void reply
to a non-NULL procedure, so the reply to both of these is wrong, for
the moment.

Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Yang Shi
5904c16d22 fs: nfs: return per memcg count for xattr shrinkers
The list_lru_count() returns the pre node count, but the new xattr
shrinkers are memcg aware, so the shrinkers should return per memcg
count by calling list_lru_shrink_count() instead.  Otherwise over-shrink
might be experienced.  The problem was spotted by visual code
inspection.

Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-10-02 08:46:46 -04:00
Benjamin Coddington
b4868b44c5 NFSv4: Wait for stateid updates after CLOSE/OPEN_DOWNGRADE
Since commit 0e0cb35b41 ("NFSv4: Handle NFS4ERR_OLD_STATEID in
CLOSE/OPEN_DOWNGRADE") the following livelock may occur if a CLOSE races
with the update of the nfs_state:

Process 1           Process 2           Server
=========           =========           ========
 OPEN file
                    OPEN file
                                        Reply OPEN (1)
                                        Reply OPEN (2)
 Update state (1)
 CLOSE file (1)
                                        Reply OLD_STATEID (1)
 CLOSE file (2)
                                        Reply CLOSE (-1)
                    Update state (2)
                    wait for state change
 OPEN file
                    wake
 CLOSE file
 OPEN file
                    wake
 CLOSE file
 ...
                    ...

We can avoid this situation by not issuing an immediate retry with a bumped
seqid when CLOSE/OPEN_DOWNGRADE receives NFS4ERR_OLD_STATEID.  Instead,
take the same approach used by OPEN and wait at least 5 seconds for
outstanding stateid updates to complete if we can detect that we're out of
sequence.

Note that after this change it is still possible (though unlikely) that
CLOSE waits a full 5 seconds, bumps the seqid, and retries -- and that
attempt races with another OPEN at the same time.  In order to avoid this
race (which would result in the livelock), update
nfs_need_update_open_stateid() to handle the case where:
 - the state is NFS_OPEN_STATE, and
 - the stateid doesn't match the current open stateid

Finally, nfs_need_update_open_stateid() is modified to be idempotent and
renamed to better suit the purpose of signaling that the stateid passed
is the next stateid in sequence.

Fixes: 0e0cb35b41 ("NFSv4: Handle NFS4ERR_OLD_STATEID in CLOSE/OPEN_DOWNGRADE")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-10-02 08:43:09 -04:00
Nick Desaulniers
fb08334bb3 nfs: remove incorrect fallthrough label
There is no case after the default from which to fallthrough to. Clang
will error in this case (unhelpfully without context, see link below)
and GCC will with -Wswitch-unreachable.

The previous commit should have just replaced the comment with a break
statement.

If we consider implicit fallthrough to be a design mistake of C, then
all case statements should be terminated with one of the following
statements:
* break
* continue
* return
* fallthrough
* goto
* (call of function with __attribute__(__noreturn__))

Fixes: 2a1390c95a69 ("nfs: Convert to use the preferred fallthrough macro")
Link: https://bugs.llvm.org/show_bug.cgi?id=47539
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-10-02 08:43:08 -04:00
Joe Perches
2efc459d06 sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
Output defects can exist in sysfs content using sprintf and snprintf.

sprintf does not know the PAGE_SIZE maximum of the temporary buffer
used for outputting sysfs content and it's possible to overrun the
PAGE_SIZE buffer length.

Add a generic sysfs_emit function that knows that the size of the
temporary buffer and ensures that no overrun is done.

Add a generic sysfs_emit_at function that can be used in multiple
call situations that also ensures that no overrun is done.

Validate the output buffer argument to be page aligned.
Validate the offset len argument to be within the PAGE_SIZE buf.

Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/884235202216d464d61ee975f7465332c86f76b2.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-02 12:02:30 +02:00
Linus Torvalds
472e5b056f pipe: remove pipe_wait() and fix wakeup race with splice
The pipe splice code still used the old model of waiting for pipe IO by
using a non-specific "pipe_wait()" that waited for any pipe event to
happen, which depended on all pipe IO being entirely serialized by the
pipe lock.  So by checking the state you were waiting for, and then
adding yourself to the wait queue before dropping the lock, you were
guaranteed to see all the wakeups.

Strictly speaking, the actual wakeups were not done under the lock, but
the pipe_wait() model still worked, because since the waiter held the
lock when checking whether it should sleep, it would always see the
current state, and the wakeup was always done after updating the state.

However, commit 0ddad21d3e ("pipe: use exclusive waits when reading or
writing") split the single wait-queue into two, and in the process also
made the "wait for event" code wait for _two_ wait queues, and that then
showed a race with the wakers that were not serialized by the pipe lock.

It's only splice that used that "pipe_wait()" model, so the problem
wasn't obvious, but Josef Bacik reports:

 "I hit a hang with fstest btrfs/187, which does a btrfs send into
  /dev/null. This works by creating a pipe, the write side is given to
  the kernel to write into, and the read side is handed to a thread that
  splices into a file, in this case /dev/null.

  The box that was hung had the write side stuck here [pipe_write] and
  the read side stuck here [splice_from_pipe_next -> pipe_wait].

  [ more details about pipe_wait() scenario ]

  The problem is we're doing the prepare_to_wait, which sets our state
  each time, however we can be woken up either with reads or writes. In
  the case above we race with the WRITER waking us up, and re-set our
  state to INTERRUPTIBLE, and thus never break out of schedule"

Josef had a patch that avoided the issue in pipe_wait() by just making
it set the state only once, but the deeper problem is that pipe_wait()
depends on a level of synchonization by the pipe mutex that it really
shouldn't.  And the whole "wait for any pipe state change" model really
isn't very good to begin with.

So rather than trying to work around things in pipe_wait(), remove that
legacy model of "wait for arbitrary pipe event" entirely, and actually
create functions that wait for the pipe actually being readable or
writable, and can do so without depending on the pipe lock serializing
everything.

Fixes: 0ddad21d3e ("pipe: use exclusive waits when reading or writing")
Link: https://lore.kernel.org/linux-fsdevel/bfa88b5ad6f069b2b679316b9e495a970130416c.1601567868.git.josef@toxicpanda.com/
Reported-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-and-tested-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-01 19:14:36 -07:00
Alexander Aring
4f2b30fd9b fs: dlm: fix race in nodeid2con
This patch fixes a race in nodeid2con in cases that we parallel running
a lookup and both will create a connection structure for the same nodeid.
It's a rare case to create a new connection structure to keep reader
lockless we just do a lookup inside the protection area again and drop
previous work if this race happens.

Fixes: a47666eb76 ("fs: dlm: make connection hash lockless")
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-10-01 09:25:07 -05:00
Qian Cai
8a018eb55e pipe: Fix memory leaks in create_pipe_files()
Calling pipe2() with O_NOTIFICATION_PIPE could results in memory
leaks unless watch_queue_init() is successful.

        In case of watch_queue_init() failure in pipe2() we are left
with inode and pipe_inode_info instances that need to be freed.  That
failure exit has been introduced in commit c73be61ced ("pipe: Add
general notification queue support") and its handling should've been
identical to nearby treatment of alloc_file_pseudo() failures - it
is dealing with the same situation.  As it is, the mainline kernel
leaks in that case.

        Another problem is that CONFIG_WATCH_QUEUE and !CONFIG_WATCH_QUEUE
cases are treated differently (and the former leaks just pipe_inode_info,
the latter - both pipe_inode_info and inode).

        Fixed by providing a dummy wacth_queue_init() in !CONFIG_WATCH_QUEUE
case and by having failures of wacth_queue_init() handled the same way
we handle alloc_file_pseudo() ones.

Fixes: c73be61ced ("pipe: Add general notification queue support")
Signed-off-by: Qian Cai <cai@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-01 09:40:35 -04:00
Jan Kara
c2bb80b8bd reiserfs: Fix oops during mount
With suitably crafted reiserfs image and mount command reiserfs will
crash when trying to verify that XATTR_ROOT directory can be looked up
in / as that recurses back to xattr code like:

 xattr_lookup+0x24/0x280 fs/reiserfs/xattr.c:395
 reiserfs_xattr_get+0x89/0x540 fs/reiserfs/xattr.c:677
 reiserfs_get_acl+0x63/0x690 fs/reiserfs/xattr_acl.c:209
 get_acl+0x152/0x2e0 fs/posix_acl.c:141
 check_acl fs/namei.c:277 [inline]
 acl_permission_check fs/namei.c:309 [inline]
 generic_permission+0x2ba/0x550 fs/namei.c:353
 do_inode_permission fs/namei.c:398 [inline]
 inode_permission+0x234/0x4a0 fs/namei.c:463
 lookup_one_len+0xa6/0x200 fs/namei.c:2557
 reiserfs_lookup_privroot+0x85/0x1e0 fs/reiserfs/xattr.c:972
 reiserfs_fill_super+0x2b51/0x3240 fs/reiserfs/super.c:2176
 mount_bdev+0x24f/0x360 fs/super.c:1417

Fix the problem by bailing from reiserfs_xattr_get() when xattrs are not
yet initialized.

CC: stable@vger.kernel.org
Reported-by: syzbot+9b33c9b118d77ff59b6f@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
2020-10-01 11:15:31 +02:00
Jens Axboe
87c4311fd2 io_uring: kill callback_head argument for io_req_task_work_add()
We always use &req->task_work anyway, no point in passing it in.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 21:00:16 -06:00
Pavel Begunkov
c1379e247a io_uring: move req preps out of io_issue_sqe()
All request preparations are done only during submission, reflect it in
the code by moving io_req_prep() much earlier into io_queue_sqe().

That's much cleaner, because it doen't expose bits to async code which
it won't ever use. Also it makes the interface harder to misuse, and
there are potential places for bugs.

For instance, __io_queue() doesn't clear @sqe before proceeding to a
next linked request, that could have been disastrous, but hopefully
there are linked requests IFF sqe==NULL, so not actually a bug.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:38:46 -06:00
Pavel Begunkov
bfe7655983 io_uring: decouple issuing and req preparation
io_issue_sqe() does two things at once, trying to prepare request and
issuing them. Split it in two and deduplicate with io_defer_prep().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:38:46 -06:00
Pavel Begunkov
73debe68b3 io_uring: remove nonblock arg from io_{rw}_prep()
All io_*_prep() functions including io_{read,write}_prep() are called
only during submission where @force_nonblock is always true. Don't keep
propagating it and instead remove the @force_nonblock argument
from prep() altogether.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:38:46 -06:00
Pavel Begunkov
a88fc40021 io_uring: set/clear IOCB_NOWAIT into io_read/write
Move setting IOCB_NOWAIT from io_prep_rw() into io_read()/io_write(), so
it's set/cleared in a single place. Also remove @force_nonblock
parameter from io_prep_rw().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:38:46 -06:00
Pavel Begunkov
2d199895d2 io_uring: remove F_NEED_CLEANUP check in *prep()
REQ_F_NEED_CLEANUP is set only by io_*_prep() and they're guaranteed to
be called only once, so there is no one who may have set the flag
before. Kill REQ_F_NEED_CLEANUP check in these *prep() handlers.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:38:46 -06:00