Commit graph

6 commits

Author SHA1 Message Date
NeilBrown
63510ce638 SUNRPC: avoid soft lockup when transmitting UDP to reachable server.
[ Upstream commit 6258cf25d5e3155c3219ab5a79b970eef7996356 ]

Prior to the commit identified below, call_transmit_status() would
handle -EPERM and other errors related to an unreachable server by
falling through to call_status() which added a 3-second delay and
handled the failure as a timeout.

Since that commit, call_transmit_status() falls through to
handle_bind().  For UDP this moves straight on to handle_connect() and
handle_transmit() so we immediately retransmit - and likely get the same
error.

This results in an indefinite loop in __rpc_execute() which triggers a
soft-lockup warning.

For the errors that indicate an unreachable server,
call_transmit_status() should fall back to call_status() as it did
before.  This cannot cause the thundering herd that the previous patch
was avoiding, as the call_status() will insert a delay.

Fixes: ed7dc973bd91 ("SUNRPC: Prevent thundering herd when the socket is not connected")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-23 23:20:09 +01:00
Dan Aloni
dab0b927f5 sunrpc: fix NFSACL RPC retry on soft mount
[ Upstream commit 0dc9f430027b8bd9073fdafdfcdeb1a073ab5594 ]

It used to be quite awhile ago since 1b63a75180c6 ('SUNRPC: Refactor
rpc_clone_client()'), in 2012, that `cl_timeout` was copied in so that
all mount parameters propagate to NFSACL clients. However since that
change, if mount options as follows are given:

    soft,timeo=50,retrans=16,vers=3

The resultant NFSACL client receives:

    cl_softrtry: 1
    cl_timeout: to_initval=60000, to_maxval=60000, to_increment=0, to_retries=2, to_exponential=0

These values lead to NFSACL operations not being retried under the
condition of transient network outages with soft mount. Instead, getacl
call fails after 60 seconds with EIO.

The simple fix is to pass the existing client's `cl_timeout` as the new
client timeout.

Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Benjamin Coddington <bcodding@redhat.com>
Link: https://lore.kernel.org/all/20231105154857.ryakhmgaptq3hb6b@gmail.com/T/
Fixes: 1b63a75180c6 ('SUNRPC: Refactor rpc_clone_client()')
Signed-off-by: Dan Aloni <dan.aloni@vastdata.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:09 +01:00
Josef Bacik
fe2b47def5 sunrpc: add a struct rpc_stats arg to rpc_create_args
[ Upstream commit 2057a48d0dd00c6a2a94ded7df2bf1d3f2a4a0da ]

We want to be able to have our rpc stats handled in a per network
namespace manner, so add an option to rpc_create_args to specify a
different rpc_stats struct instead of using the one on the rpc_program.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Stable-dep-of: 24457f1be29f ("nfs: Handle error of rpc_proc_register() in nfs_net_init().")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 11:32:41 +01:00
felix
00cb8726fb SUNRPC: Fix RPC client cleaned up the freed pipefs dentries
[ Upstream commit bfca5fb4e97c46503ddfc582335917b0cc228264 ]

RPC client pipefs dentries cleanup is in separated rpc_remove_pipedir()
workqueue,which takes care about pipefs superblock locking.
In some special scenarios, when kernel frees the pipefs sb of the
current client and immediately alloctes a new pipefs sb,
rpc_remove_pipedir function would misjudge the existence of pipefs
sb which is not the one it used to hold. As a result,
the rpc_remove_pipedir would clean the released freed pipefs dentries.

To fix this issue, rpc_remove_pipedir should check whether the
current pipefs sb is consistent with the original pipefs sb.

This error can be catched by KASAN:
=========================================================
[  250.497700] BUG: KASAN: slab-use-after-free in dget_parent+0x195/0x200
[  250.498315] Read of size 4 at addr ffff88800a2ab804 by task kworker/0:18/106503
[  250.500549] Workqueue: events rpc_free_client_work
[  250.501001] Call Trace:
[  250.502880]  kasan_report+0xb6/0xf0
[  250.503209]  ? dget_parent+0x195/0x200
[  250.503561]  dget_parent+0x195/0x200
[  250.503897]  ? __pfx_rpc_clntdir_depopulate+0x10/0x10
[  250.504384]  rpc_rmdir_depopulate+0x1b/0x90
[  250.504781]  rpc_remove_client_dir+0xf5/0x150
[  250.505195]  rpc_free_client_work+0xe4/0x230
[  250.505598]  process_one_work+0x8ee/0x13b0
...
[   22.039056] Allocated by task 244:
[   22.039390]  kasan_save_stack+0x22/0x50
[   22.039758]  kasan_set_track+0x25/0x30
[   22.040109]  __kasan_slab_alloc+0x59/0x70
[   22.040487]  kmem_cache_alloc_lru+0xf0/0x240
[   22.040889]  __d_alloc+0x31/0x8e0
[   22.041207]  d_alloc+0x44/0x1f0
[   22.041514]  __rpc_lookup_create_exclusive+0x11c/0x140
[   22.041987]  rpc_mkdir_populate.constprop.0+0x5f/0x110
[   22.042459]  rpc_create_client_dir+0x34/0x150
[   22.042874]  rpc_setup_pipedir_sb+0x102/0x1c0
[   22.043284]  rpc_client_register+0x136/0x4e0
[   22.043689]  rpc_new_client+0x911/0x1020
[   22.044057]  rpc_create_xprt+0xcb/0x370
[   22.044417]  rpc_create+0x36b/0x6c0
...
[   22.049524] Freed by task 0:
[   22.049803]  kasan_save_stack+0x22/0x50
[   22.050165]  kasan_set_track+0x25/0x30
[   22.050520]  kasan_save_free_info+0x2b/0x50
[   22.050921]  __kasan_slab_free+0x10e/0x1a0
[   22.051306]  kmem_cache_free+0xa5/0x390
[   22.051667]  rcu_core+0x62c/0x1930
[   22.051995]  __do_softirq+0x165/0x52a
[   22.052347]
[   22.052503] Last potentially related work creation:
[   22.052952]  kasan_save_stack+0x22/0x50
[   22.053313]  __kasan_record_aux_stack+0x8e/0xa0
[   22.053739]  __call_rcu_common.constprop.0+0x6b/0x8b0
[   22.054209]  dentry_free+0xb2/0x140
[   22.054540]  __dentry_kill+0x3be/0x540
[   22.054900]  shrink_dentry_list+0x199/0x510
[   22.055293]  shrink_dcache_parent+0x190/0x240
[   22.055703]  do_one_tree+0x11/0x40
[   22.056028]  shrink_dcache_for_umount+0x61/0x140
[   22.056461]  generic_shutdown_super+0x70/0x590
[   22.056879]  kill_anon_super+0x3a/0x60
[   22.057234]  rpc_kill_sb+0x121/0x200

Fixes: 0157d021d23a ("SUNRPC: handle RPC client pipefs dentries by network namespace aware routines")
Signed-off-by: felix <fuzhen5@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 11:43:19 +01:00
Trond Myklebust
63e515e6da SUNRPC: ECONNRESET might require a rebind
[ Upstream commit 4b09ca1508a60be30b2e3940264e93d7aeb5c97e ]

If connect() is returning ECONNRESET, it usually means that nothing is
listening on that port. If so, a rebind might be required in order to
obtain the new port on which the RPC service is listening.

Fixes: fd01b2597941 ("SUNRPC: ECONNREFUSED should cause a rebind.")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 11:43:19 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00