nfs4_ff_alloc_deviceid_node() reads version_count from XDR without
checking it is non-zero. When a malicious NFS server sends a pNFS
LAYOUTGET response with version_count=0, kcalloc(0, ...) returns
ZERO_SIZE_PTR (0x10). The subsequent ds_versions[0] access in
nfs4_ff_layout_ds_version() and other callers dereferences this
invalid pointer, causing an out-of-bounds read.
Add a check for version_count == 0 after parsing it from XDR, before
the allocation.
The OOB read was confirmed with KASAN: null-ptr-deref in range
[0x0000000000000010-0x0000000000000017] from accessing ZERO_SIZE_PTR.
Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Reported-by: Klaudia Kloc <klaudia@vidocsecurity.com>
Reported-by: Dawid Moczadło <dawid@vidocsecurity.com>
Tested-by: Jenny Guanni Qu <qguanni@gmail.com>
Signed-off-by: Jenny Guanni Qu <qguanni@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
In nfs4_ff_alloc_deviceid_node(), if the allocation for ds_versions fails,
the function jumps to the out_scratch label without freeing the already
allocated dsaddrs list, leading to a memory leak.
Fix this by jumping to the out_err_drain_dsaddrs label, which properly
frees the dsaddrs list before cleaning up other resources.
Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Updates common helper functions to be dss_id aware. Most cases simply
add a dss_id parameter. The has_available functions have been updated
with a loop.
Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Adds a new struct nfs4_ff_layout_ds_stripe that represents a data
server stripe within a layout. A new dynamically allocated array of
this type has been added to nfs4_ff_layout_mirror and per stripe
configuration information has been moved from the mirror type to the
stripe based on the RFC.
Signed-off-by: Jonathan Curley <jcurley@purestorage.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
When an applications get killed (SIGTERM/SIGINT) while pNFS client performs a connection
to DS, client ends in an infinite loop of connect-disconnect. This
source of the issue, it that flexfilelayoutdev#nfs4_ff_layout_prepare_ds gets an error
on nfs4_pnfs_ds_connect with status ERESTARTSYS, which is set by rpc_signal_task, but
the error is treated as transient, thus retried.
The issue is reproducible with Ctrl+C the following script(there should be ~1000 files in
a directory, client should must not have any connections to DSes):
```
echo 3 > /proc/sys/vm/drop_caches
for i in *
do
head -1 $i
done
```
The change aims to propagate the nfs4_ff_layout_prepare_ds error state
to the caller that can decide whatever this is a retryable error or not.
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Link: https://lore.kernel.org/r/20250627071751.189663-1-tigran.mkrtchyan@desy.de
Fixes: 260f32adb8 ("pNFS/flexfiles: Check the result of nfs4_pnfs_ds_connect")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
It was reported that NFS client mounts of AWS Elastic File System
(EFS) volumes is slow, this is because the AWS firewall disallows
LOCALIO (because it doesn't consider the use of NFS_LOCALIO_PROGRAM
valid), see: https://bugzilla.redhat.com/show_bug.cgi?id=2335129
Switch to performing the LOCALIO probe asynchronously to address the
potential for the NFS LOCALIO protocol being disallowed and/or slowed
by the remote server's response.
While at it, fix nfs_local_probe_async() to always take/put a
reference on the nfs_client that is using the LOCALIO protocol.
Also, unexport the nfs_local_probe() symbol and make it private to
fs/nfs/localio.c
This change has the side-effect of initially issuing reads, writes and
commits over the wire via SUNRPC until the LOCALIO probe completes.
Suggested-by: Jeff Layton <jlayton@kernel.org> # to always probe async
Fixes: 76d4cb6345 ("nfs: probe for LOCALIO when v4 client reconnects to server")
Cc: stable@vger.kernel.org # 6.14+
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Previously, we required this to value to be a power of 2 for UDP related
reasons. This patch keeps the power of 2 rule for UDP but allows more
flexibility for TCP and RDMA.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
_nfs4_pnfs_v3/v4_ds_connect do
some work
smp_wmb
ds->ds_clp = clp;
And nfs4_ff_layout_prepare_ds currently does
smp_rmb
if(ds->ds_clp)
...
This patch places the smp_rmb after the if. This ensures that following
reads only happen once nfs4_ff_layout_prepare_ds has checked that data
has been properly initialized.
Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
mirror->mirror_ds can be NULL if uninitialised, but can contain
a PTR_ERR() if call to GETDEVICEINFO failed.
Fixes: 65990d1afb ("pNFS/flexfiles: Fix a deadlock on LAYOUTGET")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # 4.10+
Get rid of the redundant parameter and rename the function
ff_layout_mirror_valid() to ff_layout_init_mirror_ds() for clarity.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
nfs4_ff_alloc_deviceid_node() guarantees that if mirror->mirror_ds is
a valid pointer, then so is mirror->mirror_ds->ds.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Pass in a pointer to the mirror rather than having to retrieve it from
the array and then verify the resulting pointer.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the DS is unresponsive, we want to just mark it as such, while
reporting the errors. If the server later returns the same deviceid
in a new layout, then we don't want to have to look it up again.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
In ff_layout_mirror_valid() we may not want to invalidate the layout
segment despite the call to GETDEVICEINFO failing. The reason is that
a read may still be able to make progress on another mirror.
So instead we let the caller (in this case nfs4_ff_layout_prepare_ds())
decide whether or not it needs to invalidate.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
While we may want to skip attempting to connect to a downed mirror
when we're deciding which mirror to select for a read, we do not
want to do so once we've committed to attempting the I/O in
ff_layout_read/write_pagelist(), or ff_layout_initiate_commit()
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When a read to the preferred mirror returns an error, the flexfiles
driver records the error in the inode list and currently marks the
layout for return before failing over the attempted read to the next
mirror.
What we actually want to do is fire off a LAYOUTERROR to notify the
MDS that there is an issue with the preferred mirror, then we fail
over. Only once we've failed to read from all mirrors should we
return the layout.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Jenny Guanni QuandTrond Myklebust
Kees Cook
Zilin GuanandTrond Myklebust
Jonathan CurleyandAnna Schumaker
Tigran MkrtchyanandTrond Myklebust
Mike SnitzerandAnna Schumaker
Jeff LaytonandTrond Myklebust
Anna SchumakerandTrond Myklebust
Baptiste LepersandTrond Myklebust
Chuck Lever
Trond MyklebustandAnna Schumaker