In the Linux kernel, the following vulnerability has been resolved:
drm/xe/ufence: Prefetch ufence addr to catch bogus address
access_ok() only checks for addr overflow so also try to read the addr
to catch invalid addr sent from userspace.
(cherry picked from commit 9408c4508483ffc60811e910a93d6425b8e63928)
In the Linux kernel, the following vulnerability has been resolved:
bpf: Check validity of link->type in bpf_link_show_fdinfo()
If a newly-added link type doesn't invoke BPF_LINK_TYPE(), accessing
bpf_link_type_strs[link->type] may result in an out-of-bounds access.
To spot such missed invocations early in the future, checking the
validity of link->type in bpf_link_show_fdinfo() and emitting a warning
when such invocations are missed.
In the Linux kernel, the following vulnerability has been resolved:
afs: Fix lock recursion
afs_wake_up_async_call() can incur lock recursion. The problem is that it
is called from AF_RXRPC whilst holding the ->notify_lock, but it tries to
take a ref on the afs_call struct in order to pass it to a work queue - but
if the afs_call is already queued, we then have an extraneous ref that must
be put... calling afs_put_call() may call back down into AF_RXRPC through
rxrpc_kernel_shutdown_call(), however, which might try taking the
->notify_lock again.
This case isn't very common, however, so defer it to a workqueue. The oops
looks something like:
BUG: spinlock recursion on CPU#0, krxrpcio/7001/1646
lock: 0xffff888141399b30, .magic: dead4ead, .owner: krxrpcio/7001/1646, .owner_cpu: 0
CPU: 0 UID: 0 PID: 1646 Comm: krxrpcio/7001 Not tainted 6.12.0-rc2-build3+ #4351
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Call Trace:
<TASK>
dump_stack_lvl+0x47/0x70
do_raw_spin_lock+0x3c/0x90
rxrpc_kernel_shutdown_call+0x83/0xb0
afs_put_call+0xd7/0x180
rxrpc_notify_socket+0xa0/0x190
rxrpc_input_split_jumbo+0x198/0x1d0
rxrpc_input_data+0x14b/0x1e0
? rxrpc_input_call_packet+0xc2/0x1f0
rxrpc_input_call_event+0xad/0x6b0
rxrpc_input_packet_on_conn+0x1e1/0x210
rxrpc_input_packet+0x3f2/0x4d0
rxrpc_io_thread+0x243/0x410
? __pfx_rxrpc_io_thread+0x10/0x10
kthread+0xcf/0xe0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x24/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
In the Linux kernel, the following vulnerability has been resolved:
bpf: Add sk_is_inet and IS_ICSK check in tls_sw_has_ctx_tx/rx
As the introduction of the support for vsock and unix sockets in sockmap,
tls_sw_has_ctx_tx/rx cannot presume the socket passed in must be IS_ICSK.
vsock and af_unix sockets have vsock_sock and unix_sock instead of
inet_connection_sock. For these sockets, tls_get_ctx may return an invalid
pointer and cause page fault in function tls_sw_ctx_rx.
BUG: unable to handle page fault for address: 0000000000040030
Workqueue: vsock-loopback vsock_loopback_work
RIP: 0010:sk_psock_strp_data_ready+0x23/0x60
Call Trace:
? __die+0x81/0xc3
? no_context+0x194/0x350
? do_page_fault+0x30/0x110
? async_page_fault+0x3e/0x50
? sk_psock_strp_data_ready+0x23/0x60
virtio_transport_recv_pkt+0x750/0x800
? update_load_avg+0x7e/0x620
vsock_loopback_work+0xd0/0x100
process_one_work+0x1a7/0x360
worker_thread+0x30/0x390
? create_worker+0x1a0/0x1a0
kthread+0x112/0x130
? __kthread_cancel_work+0x40/0x40
ret_from_fork+0x1f/0x40
v2:
- Add IS_ICSK check
v3:
- Update the commits in Fixes
In the Linux kernel, the following vulnerability has been resolved:
RDMA/siw: Add sendpage_ok() check to disable MSG_SPLICE_PAGES
While running ISER over SIW, the initiator machine encounters a warning
from skb_splice_from_iter() indicating that a slab page is being used in
send_page. To address this, it is better to add a sendpage_ok() check
within the driver itself, and if it returns 0, then MSG_SPLICE_PAGES flag
should be disabled before entering the network stack.
A similar issue has been discussed for NVMe in this thread:
https://lore.kernel.org/all/20240530142417.146696-1-ofir.gal@volumez.com/
WARNING: CPU: 0 PID: 5342 at net/core/skbuff.c:7140 skb_splice_from_iter+0x173/0x320
Call Trace:
tcp_sendmsg_locked+0x368/0xe40
siw_tx_hdt+0x695/0xa40 [siw]
siw_qp_sq_process+0x102/0xb00 [siw]
siw_sq_resume+0x39/0x110 [siw]
siw_run_sq+0x74/0x160 [siw]
kthread+0xd2/0x100
ret_from_fork+0x34/0x40
ret_from_fork_asm+0x1a/0x30
In the Linux kernel, the following vulnerability has been resolved:
smb: client: Fix use-after-free of network namespace.
Recently, we got a customer report that CIFS triggers oops while
reconnecting to a server. [0]
The workload runs on Kubernetes, and some pods mount CIFS servers
in non-root network namespaces. The problem rarely happened, but
it was always while the pod was dying.
The root cause is wrong reference counting for network namespace.
CIFS uses kernel sockets, which do not hold refcnt of the netns that
the socket belongs to. That means CIFS must ensure the socket is
always freed before its netns; otherwise, use-after-free happens.
The repro steps are roughly:
1. mount CIFS in a non-root netns
2. drop packets from the netns
3. destroy the netns
4. unmount CIFS
We can reproduce the issue quickly with the script [1] below and see
the splat [2] if CONFIG_NET_NS_REFCNT_TRACKER is enabled.
When the socket is TCP, it is hard to guarantee the netns lifetime
without holding refcnt due to async timers.
Let's hold netns refcnt for each socket as done for SMC in commit
9744d2bf1976 ("smc: Fix use-after-free in tcp_write_timer_handler().").
Note that we need to move put_net() from cifs_put_tcp_session() to
clean_demultiplex_info(); otherwise, __sock_create() still could touch a
freed netns while cifsd tries to reconnect from cifs_demultiplex_thread().
Also, maybe_get_net() cannot be put just before __sock_create() because
the code is not under RCU and there is a small chance that the same
address happened to be reallocated to another netns.
[0]:
CIFS: VFS: \\XXXXXXXXXXX has not responded in 15 seconds. Reconnecting...
CIFS: Serverclose failed 4 times, giving up
Unable to handle kernel paging request at virtual address 14de99e461f84a07
Mem abort info:
ESR = 0x0000000096000004
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x04: level 0 translation fault
Data abort info:
ISV = 0, ISS = 0x00000004
CM = 0, WnR = 0
[14de99e461f84a07] address between user and kernel address ranges
Internal error: Oops: 0000000096000004 [#1] SMP
Modules linked in: cls_bpf sch_ingress nls_utf8 cifs cifs_arc4 cifs_md4 dns_resolver tcp_diag inet_diag veth xt_state xt_connmark nf_conntrack_netlink xt_nat xt_statistic xt_MASQUERADE xt_mark xt_addrtype ipt_REJECT nf_reject_ipv4 nft_chain_nat nf_nat xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_comment nft_compat nf_tables nfnetlink overlay nls_ascii nls_cp437 sunrpc vfat fat aes_ce_blk aes_ce_cipher ghash_ce sm4_ce_cipher sm4 sm3_ce sm3 sha3_ce sha512_ce sha512_arm64 sha1_ce ena button sch_fq_codel loop fuse configfs dmi_sysfs sha2_ce sha256_arm64 dm_mirror dm_region_hash dm_log dm_mod dax efivarfs
CPU: 5 PID: 2690970 Comm: cifsd Not tainted 6.1.103-109.184.amzn2023.aarch64 #1
Hardware name: Amazon EC2 r7g.4xlarge/, BIOS 1.0 11/1/2018
pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : fib_rules_lookup+0x44/0x238
lr : __fib_lookup+0x64/0xbc
sp : ffff8000265db790
x29: ffff8000265db790 x28: 0000000000000000 x27: 000000000000bd01
x26: 0000000000000000 x25: ffff000b4baf8000 x24: ffff00047b5e4580
x23: ffff8000265db7e0 x22: 0000000000000000 x21: ffff00047b5e4500
x20: ffff0010e3f694f8 x19: 14de99e461f849f7 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000000 x12: 3f92800abd010002
x11: 0000000000000001 x10: ffff0010e3f69420 x9 : ffff800008a6f294
x8 : 0000000000000000 x7 : 0000000000000006 x6 : 0000000000000000
x5 : 0000000000000001 x4 : ffff001924354280 x3 : ffff8000265db7e0
x2 : 0000000000000000 x1 : ffff0010e3f694f8 x0 : ffff00047b5e4500
Call trace:
fib_rules_lookup+0x44/0x238
__fib_lookup+0x64/0xbc
ip_route_output_key_hash_rcu+0x2c4/0x398
ip_route_output_key_hash+0x60/0x8c
tcp_v4_connect+0x290/0x488
__inet_stream_connect+0x108/0x3d0
inet_stream_connect+0x50/0x78
kernel_connect+0x6c/0xac
generic_ip_conne
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: KVM: Mark hrtimer to expire in hard interrupt context
Like commit 2c0d278f3293f ("KVM: LAPIC: Mark hrtimer to expire in hard
interrupt context") and commit 9090825fa9974 ("KVM: arm/arm64: Let the
timer expire in hardirq context on RT"), On PREEMPT_RT enabled kernels
unmarked hrtimers are moved into soft interrupt expiry mode by default.
Then the timers are canceled from an preempt-notifier which is invoked
with disabled preemption which is not allowed on PREEMPT_RT.
The timer callback is short so in could be invoked in hard-IRQ context.
So let the timer expire on hard-IRQ context even on -RT.
This fix a "scheduling while atomic" bug for PREEMPT_RT enabled kernels:
BUG: scheduling while atomic: qemu-system-loo/1011/0x00000002
Modules linked in: amdgpu rfkill nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat ns
CPU: 1 UID: 0 PID: 1011 Comm: qemu-system-loo Tainted: G W 6.12.0-rc2+ #1774
Tainted: [W]=WARN
Hardware name: Loongson Loongson-3A5000-7A1000-1w-CRB/Loongson-LS3A5000-7A1000-1w-CRB, BIOS vUDK2018-LoongArch-V2.0.0-prebeta9 10/21/2022
Stack : ffffffffffffffff 0000000000000000 9000000004e3ea38 9000000116744000
90000001167475a0 0000000000000000 90000001167475a8 9000000005644830
90000000058dc000 90000000058dbff8 9000000116747420 0000000000000001
0000000000000001 6a613fc938313980 000000000790c000 90000001001c1140
00000000000003fe 0000000000000001 000000000000000d 0000000000000003
0000000000000030 00000000000003f3 000000000790c000 9000000116747830
90000000057ef000 0000000000000000 9000000005644830 0000000000000004
0000000000000000 90000000057f4b58 0000000000000001 9000000116747868
900000000451b600 9000000005644830 9000000003a13998 0000000010000020
00000000000000b0 0000000000000004 0000000000000000 0000000000071c1d
...
Call Trace:
[<9000000003a13998>] show_stack+0x38/0x180
[<9000000004e3ea34>] dump_stack_lvl+0x84/0xc0
[<9000000003a71708>] __schedule_bug+0x48/0x60
[<9000000004e45734>] __schedule+0x1114/0x1660
[<9000000004e46040>] schedule_rtlock+0x20/0x60
[<9000000004e4e330>] rtlock_slowlock_locked+0x3f0/0x10a0
[<9000000004e4f038>] rt_spin_lock+0x58/0x80
[<9000000003b02d68>] hrtimer_cancel_wait_running+0x68/0xc0
[<9000000003b02e30>] hrtimer_cancel+0x70/0x80
[<ffff80000235eb70>] kvm_restore_timer+0x50/0x1a0 [kvm]
[<ffff8000023616c8>] kvm_arch_vcpu_load+0x68/0x2a0 [kvm]
[<ffff80000234c2d4>] kvm_sched_in+0x34/0x60 [kvm]
[<9000000003a749a0>] finish_task_switch.isra.0+0x140/0x2e0
[<9000000004e44a70>] __schedule+0x450/0x1660
[<9000000004e45cb0>] schedule+0x30/0x180
[<ffff800002354c70>] kvm_vcpu_block+0x70/0x120 [kvm]
[<ffff800002354d80>] kvm_vcpu_halt+0x60/0x3e0 [kvm]
[<ffff80000235b194>] kvm_handle_gspr+0x3f4/0x4e0 [kvm]
[<ffff80000235f548>] kvm_handle_exit+0x1c8/0x260 [kvm]
In the Linux kernel, the following vulnerability has been resolved:
mm/thp: fix deferred split unqueue naming and locking
Recent changes are putting more pressure on THP deferred split queues:
under load revealing long-standing races, causing list_del corruptions,
"Bad page state"s and worse (I keep BUGs in both of those, so usually
don't get to see how badly they end up without). The relevant recent
changes being 6.8's mTHP, 6.10's mTHP swapout, and 6.12's mTHP swapin,
improved swap allocation, and underused THP splitting.
Before fixing locking: rename misleading folio_undo_large_rmappable(),
which does not undo large_rmappable, to folio_unqueue_deferred_split(),
which is what it does. But that and its out-of-line __callee are mm
internals of very limited usability: add comment and WARN_ON_ONCEs to
check usage; and return a bool to say if a deferred split was unqueued,
which can then be used in WARN_ON_ONCEs around safety checks (sparing
callers the arcane conditionals in __folio_unqueue_deferred_split()).
Just omit the folio_unqueue_deferred_split() from free_unref_folios(), all
of whose callers now call it beforehand (and if any forget then bad_page()
will tell) - except for its caller put_pages_list(), which itself no
longer has any callers (and will be deleted separately).
Swapout: mem_cgroup_swapout() has been resetting folio->memcg_data 0
without checking and unqueueing a THP folio from deferred split list;
which is unfortunate, since the split_queue_lock depends on the memcg
(when memcg is enabled); so swapout has been unqueueing such THPs later,
when freeing the folio, using the pgdat's lock instead: potentially
corrupting the memcg's list. __remove_mapping() has frozen refcount to 0
here, so no problem with calling folio_unqueue_deferred_split() before
resetting memcg_data.
That goes back to 5.4 commit 87eaceb3faa5 ("mm: thp: make deferred split
shrinker memcg aware"): which included a check on swapcache before adding
to deferred queue, but no check on deferred queue before adding THP to
swapcache. That worked fine with the usual sequence of events in reclaim
(though there were a couple of rare ways in which a THP on deferred queue
could have been swapped out), but 6.12 commit dafff3f4c850 ("mm: split
underused THPs") avoids splitting underused THPs in reclaim, which makes
swapcache THPs on deferred queue commonplace.
Keep the check on swapcache before adding to deferred queue? Yes: it is
no longer essential, but preserves the existing behaviour, and is likely
to be a worthwhile optimization (vmstat showed much more traffic on the
queue under swapping load if the check was removed); update its comment.
Memcg-v1 move (deprecated): mem_cgroup_move_account() has been changing
folio->memcg_data without checking and unqueueing a THP folio from the
deferred list, sometimes corrupting "from" memcg's list, like swapout.
Refcount is non-zero here, so folio_unqueue_deferred_split() can only be
used in a WARN_ON_ONCE to validate the fix, which must be done earlier:
mem_cgroup_move_charge_pte_range() first try to split the THP (splitting
of course unqueues), or skip it if that fails. Not ideal, but moving
charge has been requested, and khugepaged should repair the THP later:
nobody wants new custom unqueueing code just for this deprecated case.
The 87eaceb3faa5 commit did have the code to move from one deferred list
to another (but was not conscious of its unsafety while refcount non-0);
but that was removed by 5.6 commit fac0516b5534 ("mm: thp: don't need care
deferred split queue in memcg charge move path"), which argued that the
existence of a PMD mapping guarantees that the THP cannot be on a deferred
list. As above, false in rare cases, and now commonly false.
Backport to 6.11 should be straightforward. Earlier backports must take
care that other _deferred_list fixes and dependencies are included. There
is not a strong case for backports, but they can fix cornercases.
In the Linux kernel, the following vulnerability has been resolved:
drm/imagination: Break an object reference loop
When remaining resources are being cleaned up on driver close,
outstanding VM mappings may result in resources being leaked, due
to an object reference loop, as shown below, with each object (or
set of objects) referencing the object below it:
PVR GEM Object
GPU scheduler "finished" fence
GPU scheduler “scheduled” fence
PVR driver “done” fence
PVR Context
PVR VM Context
PVR VM Mappings
PVR GEM Object
The reference that the PVR VM Context has on the VM mappings is a
soft one, in the sense that the freeing of outstanding VM mappings
is done as part of VM context destruction; no reference counts are
involved, as is the case for all the other references in the loop.
To break the reference loop during cleanup, free the outstanding
VM mappings before destroying the PVR Context associated with the
VM context.