In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: Fix a suspicious RCU usage warning
I received the following warning while running cthon against an ontap server running pNFS:
[ 57.202521] ============================= [ 57.202522] WARNING: suspicious RCU usage [ 57.202523] 6.7.0-rc3-g2cc14f52aeb7 #41492 Not tainted [ 57.202525] ----------------------------- [ 57.202525] net/sunrpc/xprtmultipath.c:349 RCU-list traversed in non-reader section!! [ 57.202527] other info that might help us debug this:
[ 57.202528] rcu_scheduler_active = 2, debug_locks = 1 [ 57.202529] no locks held by test5/3567. [ 57.202530] stack backtrace: [ 57.202532] CPU: 0 PID: 3567 Comm: test5 Not tainted 6.7.0-rc3-g2cc14f52aeb7 #41492 5b09971b4965c0aceba19f3eea324a4a806e227e [ 57.202534] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022 [ 57.202536] Call Trace: [ 57.202537] <TASK> [ 57.202540] dump_stack_lvl+0x77/0xb0 [ 57.202551] lockdep_rcu_suspicious+0x154/0x1a0 [ 57.202556] rpc_xprt_switch_has_addr+0x17c/0x190 [sunrpc ebe02571b9a8ceebf7d98e71675af20c19bdb1f6] [ 57.202596] rpc_clnt_setup_test_and_add_xprt+0x50/0x180 [sunrpc ebe02571b9a8ceebf7d98e71675af20c19bdb1f6] [ 57.202621] ? rpc_clnt_add_xprt+0x254/0x300 [sunrpc ebe02571b9a8ceebf7d98e71675af20c19bdb1f6] [ 57.202646] rpc_clnt_add_xprt+0x27a/0x300 [sunrpc ebe02571b9a8ceebf7d98e71675af20c19bdb1f6] [ 57.202671] ? __pfx_rpc_clnt_setup_test_and_add_xprt+0x10/0x10 [sunrpc ebe02571b9a8ceebf7d98e71675af20c19bdb1f6] [ 57.202696] nfs4_pnfs_ds_connect+0x345/0x760 [nfsv4 c716d88496ded0ea6d289bbea684fa996f9b57a9] [ 57.202728] ? __pfx_nfs4_test_session_trunk+0x10/0x10 [nfsv4 c716d88496ded0ea6d289bbea684fa996f9b57a9] [ 57.202754] nfs4_fl_prepare_ds+0x75/0xc0 [nfs_layout_nfsv41_files e3a4187f18ae8a27b630f9feae6831b584a9360a] [ 57.202760] filelayout_write_pagelist+0x4a/0x200...
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:NI:NA:H5.5/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H