Before traversing a referral and performing a mount, the mounted-on
directory looks strange:
dr-xr-xr-x. 2 4294967294 4294967294 0 Dec 31 1969 dir.0
nfs4_get_referral is wiping out any cached attributes with what was
returned via GETATTR(fs_locations), but the bit mask for that
operation does not request any file attributes.
Retrieve owner and timestamp information so that the memcpy in
nfs4_get_referral fills in more attributes.
Changes since v1:
- Don't request attributes that the client unconditionally replaces
- Request only MOUNTED_ON_FILEID or FILEID attribute, not both
- encode_fs_locations() doesn't use the third bitmask word
Fixes: 6b97fd3da1ea ("NFSv4: Follow a referral")
Suggested-by: Pradeep Thomas <pradeepthomas@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Addresses-Coverity-ID: 703509
Addresses-Coverity-ID: 703510
Addresses-Coverity-ID: 703511
Addresses-Coverity-ID: 703512
Addresses-Coverity-ID: 703513
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Publishing of net pointer is not safe, use net->ns.inum as net ID
[ 171.391947] RPC: created new rpcb local clients
(rpcb_local_clnt: ..., rpcb_local_clnt4: ...) for net f00001e7
[ 171.767188] NFSD: starting 90-second grace period (net f00001e7)
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Publishing of net pointer is not safe,
use net->ns.inum instead
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Be sure that all_clients list initialized in net_init hook was return
to initial state.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Be sure that nfs_client_list and nfs_volume_list lists initialized
in net_init hook were return to initial state in net_exit hook.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add a jump target so that a bit of exception handling can be better reused
at the end of this function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When decoding a CLOSE, replace the stateid returned by the server
with the "invalid special stateid" described in RFC5661, Section 8.2.3.
In nfs_set_open_stateid_locked, ignore stateids from closed state.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In nfs_set_open_stateid_locked, we must ignore stateids from closed state.
Reported-by: Andrew W Elble <aweits@rit.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If our layoutreturn returns an NFS4ERR_OLD_STATEID, then try to
update the stateid and retry.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If our layoutreturn on close operation returns an NFS4ERR_OLD_STATEID,
then try to update the stateid and retry. We know that there should
be no further LAYOUTGET requests being launched.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the stateid is no longer recognised on the server, either due to a
restart, or due to a competing CLOSE call, then we do not have to
retry. Any open contexts that triggered a reopen of the file, will
also act as triggers for any CLOSE for the updated stateids.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If we're racing with an OPEN, then retry the operation instead of
declaring it a success.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
[Andrew W Elble: Fix a typo in nfs4_refresh_open_stateid]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
On successful rename, the "old_dentry" is retained and is attached to
the "new_dir", so we need to call nfs_set_verifier() accordingly.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the server that does not implement NFSv4.1 persistent session
semantics reboots while we are performing an exclusive create,
then the return value of NFS4ERR_DELAY when we replay the open
during the grace period causes us to lose the verifier.
When the grace period expires, and we present a new verifier,
the server will then correctly reply NFS4ERR_EXIST.
This commit ensures that we always present the same verifier when
replaying the OPEN.
Reported-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Ben Coddington has noted the following race between OPEN and CLOSE
on a single client.
Process 1 Process 2 Server
========= ========= ======
1) OPEN file
2) OPEN file
3) Process OPEN (1) seqid=1
4) Process OPEN (2) seqid=2
5) Reply OPEN (2)
6) Receive reply (2)
7) new stateid, seqid=2
8) CLOSE file, using
stateid w/ seqid=2
9) Reply OPEN (1)
10( Process CLOSE (8)
11) Reply CLOSE (8)
12) Forget stateid
file closed
13) Receive reply (7)
14) Forget stateid
file closed.
15) Receive reply (1).
16) New stateid seqid=1
is really the same
stateid that was
closed.
IOW: the reply to the first OPEN is delayed. Since "Process 2" does
not wait before closing the file, and it does not cache the closed
stateid, then when the delayed reply is finally received, it is treated
as setting up a new stateid by the client.
The fix is to ensure that the client processes the OPEN and CLOSE calls
in the same order in which the server processed them.
This commit ensures that we examine the seqid of the stateid
returned by OPEN. If it is a new stateid, we assume the seqid
must be equal to the value 1, and that each state transition
increments the seqid value by 1 (See RFC7530, Section 9.1.4.2,
and RFC5661, Section 8.2.2).
If the tracker sees that an OPEN returns with a seqid that is greater
than the cached seqid + 1, then it bumps a flag to ensure that the
caller waits for the RPCs carrying the missing seqids to complete.
Note that there can still be pathologies where the server crashes before
it can even send us the missing seqids. Since the OPEN call is still
holding a slot when it waits here, that could cause the recovery to
stall forever. To avoid that, we time out after a 5 second wait.
Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Display information about the RPC procedure being requested in the
trace log. This sometimes critical information cannot always be
derived from other RPC trace entries.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The rpc_task_begin trace point always display a task ID of zero.
Move the trace point call site so that it picks up the new task ID.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Bool initializations should use true and false. Bool tests don't need
comparisons.
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
There isn't an obvious way to acquire and release the RCU lock during a
tracepoint, so we can't use the rpc_peeraddr2str() function here.
Instead, rely on the client's cl_hostname, which should have similar
enough information without needing an rcu_dereference().
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Cc: stable@vger.kernel.org # v3.12
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Credit work contributed by Oracle engineers since 2014.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up. This include should have been removed by
commit 23826c7aeac7 ("xprtrdma: Serialize credit accounting again").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: C-structure style XDR encoding and decoding logic has
been replaced over the past several merge windows on both the
client and server. These data structures are no longer used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Lift the Send and LocalInv completion handlers out of soft IRQ mode
to make room for other work. Also, move the Send CQ to a different
CPU than the CPU where the Receive CQ is running, for improved
scalability.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Pull overlayfs updates from Miklos Szeredi:
- Report constant st_ino values across copy-up even if underlying
layers are on different filesystems, but using different st_dev
values for each layer.
Ideally we'd report the same st_dev across the overlay, and it's
possible to do for filesystems that use only 32bits for st_ino by
unifying the inum space. It would be nice if it wasn't a choice of 32
or 64, rather filesystems could report their current maximum (that
could change on resize, so it wouldn't be set in stone).
- miscellaneus fixes and a cleanup of ovl_fill_super(), that was long
overdue.
- created a path_put_init() helper that clears out the pointers after
putting the ref.
I think this could be useful elsewhere, so added it to <linux/path.h>
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (30 commits)
ovl: remove unneeded arg from ovl_verify_origin()
ovl: Put upperdentry if ovl_check_origin() fails
ovl: rename ufs to ofs
ovl: clean up getting lower layers
ovl: clean up workdir creation
ovl: clean up getting upper layer
ovl: move ovl_get_workdir() and ovl_get_lower_layers()
ovl: reduce the number of arguments for ovl_workdir_create()
ovl: change order of setup in ovl_fill_super()
ovl: factor out ovl_free_fs() helper
ovl: grab reference to workbasedir early
ovl: split out ovl_get_indexdir() from ovl_fill_super()
ovl: split out ovl_get_lower_layers() from ovl_fill_super()
ovl: split out ovl_get_workdir() from ovl_fill_super()
ovl: split out ovl_get_upper() from ovl_fill_super()
ovl: split out ovl_get_lowerstack() from ovl_fill_super()
ovl: split out ovl_get_workpath() from ovl_fill_super()
ovl: split out ovl_get_upperpath() from ovl_fill_super()
ovl: use path_put_init() in error paths for ovl_fill_super()
vfs: add path_put_init()
...
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Merge tag 'locks-v4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux
Pull file locking update from Jeff Layton:
"A couple of fixes for a patch that went into v4.14, and the bug report
just came in a few days ago.. It passes my (minimal) testing, and has
been in linux-next for a few days now.
I also would like to get my address changed in MAINTAINERS to clear
that hurdle"
* tag 'locks-v4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
fcntl: don't cap l_start and l_end values for F_GETLK64 in compat syscall
fcntl: don't leak fd reference when fixup_compat_flock fails
MAINTAINERS: s/jlayton@poochiereds.net/jlayton@kernel.org/
Pull cramfs updates from Al Viro:
"Nicolas Pitre's cramfs work"
* 'work.cramfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
cramfs: rehabilitate it
cramfs: add mmap support
cramfs: implement uncompressed and arbitrary data block positioning
cramfs: direct memory access support
Pull misc vfs updates from Al Viro:
"Assorted stuff, really no common topic here"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: grab the lock instead of blocking in __fd_install during resizing
vfs: stop clearing close on exec when closing a fd
include/linux/fs.h: fix comment about struct address_space
fs: make fiemap work from compat_ioctl
coda: fix 'kernel memory exposure attempt' in fsync
pstore: remove unneeded unlikely()
vfs: remove unneeded unlikely()
stubs for mount_bdev() and kill_block_super() in !CONFIG_BLOCK case
make vfs_ustat() static
do_handle_open() should be static
elf_fdpic: fix unused variable warning
fold destroy_super() into __put_super()
new helper: destroy_unused_super()
fix address space warnings in ipc/
acct.h: get rid of detritus
Pull get_user_pages_fast() conversion from Al Viro:
"A bunch of places switched to get_user_pages_fast()"
* 'work.get_user_pages_fast' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ceph: use get_user_pages_fast()
pvr2fs: use get_user_pages_fast()
atomisp: use get_user_pages_fast()
st: use get_user_pages_fast()
via_dmablit(): use get_user_pages_fast()
fsl_hypervisor: switch to get_user_pages_fast()
rapidio: switch to get_user_pages_fast()
vchiq_2835_arm: switch to get_user_pages_fast()
Pull iov_iter updates from Al Viro:
- bio_{map,copy}_user_iov() series; those are cleanups - fixes from the
same pile went into mainline (and stable) in late September.
- fs/iomap.c iov_iter-related fixes
- new primitive - iov_iter_for_each_range(), which applies a function
to kernel-mapped segments of an iov_iter.
Usable for kvec and bvec ones, the latter does kmap()/kunmap() around
the callback. _Not_ usable for iovec- or pipe-backed iov_iter; the
latter is not hard to fix if the need ever appears, the former is by
design.
Another related primitive will have to wait for the next cycle - it
passes page + offset + size instead of pointer + size, and that one
will be usable for everything _except_ kvec. Unfortunately, that one
didn't get exposure in -next yet, so...
- a bit more lustre iov_iter work, including a use case for
iov_iter_for_each_range() (checksum calculation)
- vhost/scsi leak fix in failure exit
- misc cleanups and detritectomy...
* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (21 commits)
iomap_dio_actor(): fix iov_iter bugs
switch ksocknal_lib_recv_...() to use of iov_iter_for_each_range()
lustre: switch struct ksock_conn to iov_iter
vhost/scsi: switch to iov_iter_get_pages()
fix a page leak in vhost_scsi_iov_to_sgl() error recovery
new primitive: iov_iter_for_each_range()
lnet_return_rx_credits_locked: don't abuse list_entry
xen: don't open-code iov_iter_kvec()
orangefs: remove detritus from struct orangefs_kiocb_s
kill iov_shorten()
bio_alloc_map_data(): do bmd->iter setup right there
bio_copy_user_iov(): saner bio size calculation
bio_map_user_iov(): get rid of copying iov_iter
bio_copy_from_iter(): get rid of copying iov_iter
move more stuff down into bio_copy_user_iov()
blk_rq_map_user_iov(): move iov_iter_advance() down
bio_map_user_iov(): get rid of the iov_for_each()
bio_map_user_iov(): move alignment check into the main loop
don't rely upon subsequent bio_add_pc_page() calls failing
... and with iov_iter_get_pages_alloc() it becomes even simpler
...
Pull compat and uaccess updates from Al Viro:
- {get,put}_compat_sigset() series
- assorted compat ioctl stuff
- more set_fs() elimination
- a few more timespec64 conversions
- several removals of pointless access_ok() in places where it was
followed only by non-__ variants of primitives
* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits)
coredump: call do_unlinkat directly instead of sys_unlink
fs: expose do_unlinkat for built-in callers
ext4: take handling of EXT4_IOC_GROUP_ADD into a helper, get rid of set_fs()
ipmi: get rid of pointless access_ok()
pi433: sanitize ioctl
cxlflash: get rid of pointless access_ok()
mtdchar: get rid of pointless access_ok()
r128: switch compat ioctls to drm_ioctl_kernel()
selection: get rid of field-by-field copyin
VT_RESIZEX: get rid of field-by-field copyin
i2c compat ioctls: move to ->compat_ioctl()
sched_rr_get_interval(): move compat to native, get rid of set_fs()
mips: switch to {get,put}_compat_sigset()
sparc: switch to {get,put}_compat_sigset()
s390: switch to {get,put}_compat_sigset()
ppc: switch to {get,put}_compat_sigset()
parisc: switch to {get,put}_compat_sigset()
get_compat_sigset()
get rid of {get,put}_compat_itimerspec()
io_getevents: Use timespec64 to represent timeouts
...
Pull more block layer updates from Jens Axboe:
"A followup pull request, with some parts that either needed a bit more
testing before going in, merge sync, or just later arriving fixes.
This contains:
- Timer related updates from Kees. These were purposefully delayed
since I didn't want to pull in a later v4.14-rc tag to my block
tree.
- ide-cd prep sense buffer fix from Bart. Also delayed, as not to
clash with the late fix we put into 4.14-rc.
- Small BFQ updates series from Luca and Paolo.
- Single nvmet fix from James, fixing a non-functional case there.
- Bio fast clone fix from Michael, which made bcache return the wrong
data for some cases.
- Legacy IO path regression hang fix from Ming"
* 'for-linus' of git://git.kernel.dk/linux-block:
bio: ensure __bio_clone_fast copies bi_partno
nvmet_fc: fix better length checking
block: wake up all tasks blocked in get_request()
block, bfq: move debug blkio stats behind CONFIG_DEBUG_BLK_CGROUP
block, bfq: update blkio stats outside the scheduler lock
block, bfq: add missing invocations of bfqg_stats_update_io_add/remove
doc, block, bfq: update max IOPS sustainable with BFQ
ide: Make ide_cdrom_prep_fs() initialize the sense buffer pointer
md: Convert timers to use timer_setup()
block: swim3: Convert timers to use timer_setup()
block/aoe: Convert timers to use timer_setup()
amifloppy: Convert timers to use timer_setup()
block/floppy: Convert callback to pass timer_list
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable nfs_client.cl_count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable nfs_lock_context.count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable nfs4_lock_state.ls_count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable nfs_cache_defer_req.count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable nfs4_ff_layout_mirror.ref is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable pnfs_layout_hdr.plh_refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable nfs4_pnfs_ds.ds_count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the previous request on a slot was interrupted before it was
processed by the server, then our slot sequence number may be out of whack,
and so we try the next operation using the old sequence number.
The problem with this, is that not all servers check to see that the
client is replaying the same operations as previously when they decide
to go to the replay cache, and so instead of the expected error of
NFS4ERR_SEQ_FALSE_RETRY, we get a replay of the old reply, which could
(if the operations match up) be mistaken by the client for a new reply.
To fix this, we attempt to send a COMPOUND containing only the SEQUENCE op
in order to resync our slot sequence number.
Cc: Olga Kornievskaia <olga.kornievskaia@gmail.com>
[olga.kornievskaia@gmail.com: fix an Oops]
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The sendctx circular queue now guarantees that xprtrdma cannot
overflow the Send Queue, so remove the remaining bits of the
original Send WQE counting mechanism.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When an RPC Call includes a file data payload, that payload can come
from pages in the page cache, or a user buffer (for direct I/O).
If the payload can fit inline, xprtrdma includes it in the Send
using a scatter-gather technique. xprtrdma mustn't allow the RPC
consumer to re-use the memory where that payload resides before the
Send completes. Otherwise, the new contents of that memory would be
exposed by an HCA retransmit of the Send operation.
So, block RPC completion on Send completion, but only in the case
where a separate file data payload is part of the Send. This
prevents the reuse of that memory while it is still part of a Send
operation without an undue cost to other cases.
Waiting is avoided in the common case because typically the Send
will have completed long before the RPC Reply arrives.
These days, an RPC timeout will trigger a disconnect, which tears
down the QP. The disconnect flushes all waiting Sends. This bounds
the amount of time the reply handler has to wait for a Send
completion.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Invoke a common routine for releasing hardware resources (for
example, invalidating MRs). This needs to be done whether an
RPC Reply has arrived or the RPC was terminated early.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
