| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
sched/fair: Prevent dead task groups from regaining cfs_rq's
Kevin is reporting crashes which point to a use-after-free of a cfs_rq
in update_blocked_averages(). Initial debugging revealed that we've
live cfs_rq's (on_list=1) in an about to be kfree()'d task group in
free_fair_sched_group(). However, it was unclear how that can happen.
His kernel config happened to lead to a layout of struct sched_entity
that put the 'my_q' member directly into the middle of the object
which makes it incidentally overlap with SLUB's freelist pointer.
That, in combination with SLAB_FREELIST_HARDENED's freelist pointer
mangling, leads to a reliable access violation in form of a #GP which
made the UAF fail fast.
Michal seems to have run into the same issue[1]. He already correctly
diagnosed that commit a7b359fc6a37 ("sched/fair: Correctly insert
cfs_rq's to list on unthrottle") is causing the preconditions for the
UAF to happen by re-adding cfs_rq's also to task groups that have no
more running tasks, i.e. also to dead ones. His analysis, however,
misses the real root cause and it cannot be seen from the crash
backtrace only, as the real offender is tg_unthrottle_up() getting
called via sched_cfs_period_timer() via the timer interrupt at an
inconvenient time.
When unregister_fair_sched_group() unlinks all cfs_rq's from the dying
task group, it doesn't protect itself from getting interrupted. If the
timer interrupt triggers while we iterate over all CPUs or after
unregister_fair_sched_group() has finished but prior to unlinking the
task group, sched_cfs_period_timer() will execute and walk the list of
task groups, trying to unthrottle cfs_rq's, i.e. re-add them to the
dying task group. These will later -- in free_fair_sched_group() -- be
kfree()'ed while still being linked, leading to the fireworks Kevin
and Michal are seeing.
To fix this race, ensure the dying task group gets unlinked first.
However, simply switching the order of unregistering and unlinking the
task group isn't sufficient, as concurrent RCU walkers might still see
it, as can be seen below:
CPU1: CPU2:
: timer IRQ:
: do_sched_cfs_period_timer():
: :
: distribute_cfs_runtime():
: rcu_read_lock();
: :
: unthrottle_cfs_rq():
sched_offline_group(): :
: walk_tg_tree_from(…,tg_unthrottle_up,…):
list_del_rcu(&tg->list); :
(1) : list_for_each_entry_rcu(child, &parent->children, siblings)
: :
(2) list_del_rcu(&tg->siblings); :
: tg_unthrottle_up():
unregister_fair_sched_group(): struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
: :
list_del_leaf_cfs_rq(tg->cfs_rq[cpu]); :
: :
: if (!cfs_rq_is_decayed(cfs_rq) || cfs_rq->nr_running)
(3) : list_add_leaf_cfs_rq(cfs_rq);
: :
: :
: :
: :
:
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Set send and receive CQ before forwarding to the driver
Preset both receive and send CQ pointers prior to call to the drivers and
overwrite it later again till the mlx4 is going to be changed do not
overwrite ibqp properties.
This change is needed for mlx5, because in case of QP creation failure, it
will go to the path of QP destroy which relies on proper CQ pointers.
BUG: KASAN: use-after-free in create_qp.cold+0x164/0x16e [mlx5_ib]
Write of size 8 at addr ffff8880064c55c0 by task a.out/246
CPU: 0 PID: 246 Comm: a.out Not tainted 5.15.0+ #291
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack_lvl+0x45/0x59
print_address_description.constprop.0+0x1f/0x140
kasan_report.cold+0x83/0xdf
create_qp.cold+0x164/0x16e [mlx5_ib]
mlx5_ib_create_qp+0x358/0x28a0 [mlx5_ib]
create_qp.part.0+0x45b/0x6a0 [ib_core]
ib_create_qp_user+0x97/0x150 [ib_core]
ib_uverbs_handler_UVERBS_METHOD_QP_CREATE+0x92c/0x1250 [ib_uverbs]
ib_uverbs_cmd_verbs+0x1c38/0x3150 [ib_uverbs]
ib_uverbs_ioctl+0x169/0x260 [ib_uverbs]
__x64_sys_ioctl+0x866/0x14d0
do_syscall_64+0x3d/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
Allocated by task 246:
kasan_save_stack+0x1b/0x40
__kasan_kmalloc+0xa4/0xd0
create_qp.part.0+0x92/0x6a0 [ib_core]
ib_create_qp_user+0x97/0x150 [ib_core]
ib_uverbs_handler_UVERBS_METHOD_QP_CREATE+0x92c/0x1250 [ib_uverbs]
ib_uverbs_cmd_verbs+0x1c38/0x3150 [ib_uverbs]
ib_uverbs_ioctl+0x169/0x260 [ib_uverbs]
__x64_sys_ioctl+0x866/0x14d0
do_syscall_64+0x3d/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
Freed by task 246:
kasan_save_stack+0x1b/0x40
kasan_set_track+0x1c/0x30
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0x10c/0x150
slab_free_freelist_hook+0xb4/0x1b0
kfree+0xe7/0x2a0
create_qp.part.0+0x52b/0x6a0 [ib_core]
ib_create_qp_user+0x97/0x150 [ib_core]
ib_uverbs_handler_UVERBS_METHOD_QP_CREATE+0x92c/0x1250 [ib_uverbs]
ib_uverbs_cmd_verbs+0x1c38/0x3150 [ib_uverbs]
ib_uverbs_ioctl+0x169/0x260 [ib_uverbs]
__x64_sys_ioctl+0x866/0x14d0
do_syscall_64+0x3d/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: skb_linearize the head skb when reassembling msgs
It's not a good idea to append the frag skb to a skb's frag_list if
the frag_list already has skbs from elsewhere, such as this skb was
created by pskb_copy() where the frag_list was cloned (all the skbs
in it were skb_get'ed) and shared by multiple skbs.
However, the new appended frag skb should have been only seen by the
current skb. Otherwise, it will cause use after free crashes as this
appended frag skb are seen by multiple skbs but it only got skb_get
called once.
The same thing happens with a skb updated by pskb_may_pull() with a
skb_cloned skb. Li Shuang has reported quite a few crashes caused
by this when doing testing over macvlan devices:
[] kernel BUG at net/core/skbuff.c:1970!
[] Call Trace:
[] skb_clone+0x4d/0xb0
[] macvlan_broadcast+0xd8/0x160 [macvlan]
[] macvlan_process_broadcast+0x148/0x150 [macvlan]
[] process_one_work+0x1a7/0x360
[] worker_thread+0x30/0x390
[] kernel BUG at mm/usercopy.c:102!
[] Call Trace:
[] __check_heap_object+0xd3/0x100
[] __check_object_size+0xff/0x16b
[] simple_copy_to_iter+0x1c/0x30
[] __skb_datagram_iter+0x7d/0x310
[] __skb_datagram_iter+0x2a5/0x310
[] skb_copy_datagram_iter+0x3b/0x90
[] tipc_recvmsg+0x14a/0x3a0 [tipc]
[] ____sys_recvmsg+0x91/0x150
[] ___sys_recvmsg+0x7b/0xc0
[] kernel BUG at mm/slub.c:305!
[] Call Trace:
[] <IRQ>
[] kmem_cache_free+0x3ff/0x400
[] __netif_receive_skb_core+0x12c/0xc40
[] ? kmem_cache_alloc+0x12e/0x270
[] netif_receive_skb_internal+0x3d/0xb0
[] ? get_rx_page_info+0x8e/0xa0 [be2net]
[] be_poll+0x6ef/0xd00 [be2net]
[] ? irq_exit+0x4f/0x100
[] net_rx_action+0x149/0x3b0
...
This patch is to fix it by linearizing the head skb if it has frag_list
set in tipc_buf_append(). Note that we choose to do this before calling
skb_unshare(), as __skb_linearize() will avoid skb_copy(). Also, we can
not just drop the frag_list either as the early time. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix a use-after-free
looks like we forget to set ttm->sg to NULL.
Hit panic below
[ 1235.844104] general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b7b4b: 0000 [#1] SMP DEBUG_PAGEALLOC NOPTI
[ 1235.989074] Call Trace:
[ 1235.991751] sg_free_table+0x17/0x20
[ 1235.995667] amdgpu_ttm_backend_unbind.cold+0x4d/0xf7 [amdgpu]
[ 1236.002288] amdgpu_ttm_backend_destroy+0x29/0x130 [amdgpu]
[ 1236.008464] ttm_tt_destroy+0x1e/0x30 [ttm]
[ 1236.013066] ttm_bo_cleanup_memtype_use+0x51/0xa0 [ttm]
[ 1236.018783] ttm_bo_release+0x262/0xa50 [ttm]
[ 1236.023547] ttm_bo_put+0x82/0xd0 [ttm]
[ 1236.027766] amdgpu_bo_unref+0x26/0x50 [amdgpu]
[ 1236.032809] amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu+0x7aa/0xd90 [amdgpu]
[ 1236.040400] kfd_ioctl_alloc_memory_of_gpu+0xe2/0x330 [amdgpu]
[ 1236.046912] kfd_ioctl+0x463/0x690 [amdgpu] |
| In the Linux kernel, the following vulnerability has been resolved:
net/tls: Fix use-after-free after the TLS device goes down and up
When a netdev with active TLS offload goes down, tls_device_down is
called to stop the offload and tear down the TLS context. However, the
socket stays alive, and it still points to the TLS context, which is now
deallocated. If a netdev goes up, while the connection is still active,
and the data flow resumes after a number of TCP retransmissions, it will
lead to a use-after-free of the TLS context.
This commit addresses this bug by keeping the context alive until its
normal destruction, and implements the necessary fallbacks, so that the
connection can resume in software (non-offloaded) kTLS mode.
On the TX side tls_sw_fallback is used to encrypt all packets. The RX
side already has all the necessary fallbacks, because receiving
non-decrypted packets is supported. The thing needed on the RX side is
to block resync requests, which are normally produced after receiving
non-decrypted packets.
The necessary synchronization is implemented for a graceful teardown:
first the fallbacks are deployed, then the driver resources are released
(it used to be possible to have a tls_dev_resync after tls_dev_del).
A new flag called TLS_RX_DEV_DEGRADED is added to indicate the fallback
mode. It's used to skip the RX resync logic completely, as it becomes
useless, and some objects may be released (for example, resync_async,
which is allocated and freed by the driver). |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet: fix freeing unallocated p2pmem
In case p2p device was found but the p2p pool is empty, the nvme target
is still trying to free the sgl from the p2p pool instead of the
regular sgl pool and causing a crash (BUG() is called). Instead, assign
the p2p_dev for the request only if it was allocated from p2p pool.
This is the crash that was caused:
[Sun May 30 19:13:53 2021] ------------[ cut here ]------------
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
[Sun May 30 19:13:53 2021] invalid opcode: 0000 [#1] SMP PTI
...
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
...
[Sun May 30 19:13:53 2021] RIP: 0010:gen_pool_free_owner+0xa8/0xb0
...
[Sun May 30 19:13:53 2021] Call Trace:
[Sun May 30 19:13:53 2021] ------------[ cut here ]------------
[Sun May 30 19:13:53 2021] pci_free_p2pmem+0x2b/0x70
[Sun May 30 19:13:53 2021] pci_p2pmem_free_sgl+0x4f/0x80
[Sun May 30 19:13:53 2021] nvmet_req_free_sgls+0x1e/0x80 [nvmet]
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
[Sun May 30 19:13:53 2021] nvmet_rdma_release_rsp+0x4e/0x1f0 [nvmet_rdma]
[Sun May 30 19:13:53 2021] nvmet_rdma_send_done+0x1c/0x60 [nvmet_rdma] |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: abort in rename_exchange if we fail to insert the second ref
Error injection stress uncovered a problem where we'd leave a dangling
inode ref if we failed during a rename_exchange. This happens because
we insert the inode ref for one side of the rename, and then for the
other side. If this second inode ref insert fails we'll leave the first
one dangling and leave a corrupt file system behind. Fix this by
aborting if we did the insert for the first inode ref. |
| In the Linux kernel, the following vulnerability has been resolved:
xen-netback: take a reference to the RX task thread
Do this in order to prevent the task from being freed if the thread
returns (which can be triggered by the frontend) before the call to
kthread_stop done as part of the backend tear down. Not taking the
reference will lead to a use-after-free in that scenario. Such
reference was taken before but dropped as part of the rework done in
2ac061ce97f4.
Reintroduce the reference taking and add a comment this time
explaining why it's needed.
This is XSA-374 / CVE-2021-28691. |
| In the Linux kernel, the following vulnerability has been resolved:
inet: fully convert sk->sk_rx_dst to RCU rules
syzbot reported various issues around early demux,
one being included in this changelog [1]
sk->sk_rx_dst is using RCU protection without clearly
documenting it.
And following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv()
are not following standard RCU rules.
[a] dst_release(dst);
[b] sk->sk_rx_dst = NULL;
They look wrong because a delete operation of RCU protected
pointer is supposed to clear the pointer before
the call_rcu()/synchronize_rcu() guarding actual memory freeing.
In some cases indeed, dst could be freed before [b] is done.
We could cheat by clearing sk_rx_dst before calling
dst_release(), but this seems the right time to stick
to standard RCU annotations and debugging facilities.
[1]
BUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline]
BUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
Read of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204
CPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247
__kasan_report mm/kasan/report.c:433 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:450
dst_check include/net/dst.h:470 [inline]
tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340
ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583
ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]
ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644
__netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]
__netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556
__netif_receive_skb_list net/core/dev.c:5608 [inline]
netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699
gro_normal_list net/core/dev.c:5853 [inline]
gro_normal_list net/core/dev.c:5849 [inline]
napi_complete_done+0x1f1/0x880 net/core/dev.c:6590
virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557
__napi_poll+0xaf/0x440 net/core/dev.c:7023
napi_poll net/core/dev.c:7090 [inline]
net_rx_action+0x801/0xb40 net/core/dev.c:7177
__do_softirq+0x29b/0x9c2 kernel/softirq.c:558
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240
asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0033:0x7f5e972bfd57
Code: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e <48> 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73
RSP: 002b:00007fff8a413210 EFLAGS: 00000283
RAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45
RDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45
RBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9
R10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0
R13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019
</TASK>
Allocated by task 13:
kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
__kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467
kasan_slab_alloc include/linux/kasan.h:259 [inline]
slab_post_alloc_hook mm/slab.h:519 [inline]
slab_alloc_node mm/slub.c:3234 [inline]
slab_alloc mm/slub.c:3242 [inline]
kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247
dst_alloc+0x146/0x1f0 net/core/dst.c:92
rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613
ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:234
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: x86/mmu: Don't advance iterator after restart due to yielding
After dropping mmu_lock in the TDP MMU, restart the iterator during
tdp_iter_next() and do not advance the iterator. Advancing the iterator
results in skipping the top-level SPTE and all its children, which is
fatal if any of the skipped SPTEs were not visited before yielding.
When zapping all SPTEs, i.e. when min_level == root_level, restarting the
iter and then invoking tdp_iter_next() is always fatal if the current gfn
has as a valid SPTE, as advancing the iterator results in try_step_side()
skipping the current gfn, which wasn't visited before yielding.
Sprinkle WARNs on iter->yielded being true in various helpers that are
often used in conjunction with yielding, and tag the helper with
__must_check to reduce the probabily of improper usage.
Failing to zap a top-level SPTE manifests in one of two ways. If a valid
SPTE is skipped by both kvm_tdp_mmu_zap_all() and kvm_tdp_mmu_put_root(),
the shadow page will be leaked and KVM will WARN accordingly.
WARNING: CPU: 1 PID: 3509 at arch/x86/kvm/mmu/tdp_mmu.c:46 [kvm]
RIP: 0010:kvm_mmu_uninit_tdp_mmu+0x3e/0x50 [kvm]
Call Trace:
<TASK>
kvm_arch_destroy_vm+0x130/0x1b0 [kvm]
kvm_destroy_vm+0x162/0x2a0 [kvm]
kvm_vcpu_release+0x34/0x60 [kvm]
__fput+0x82/0x240
task_work_run+0x5c/0x90
do_exit+0x364/0xa10
? futex_unqueue+0x38/0x60
do_group_exit+0x33/0xa0
get_signal+0x155/0x850
arch_do_signal_or_restart+0xed/0x750
exit_to_user_mode_prepare+0xc5/0x120
syscall_exit_to_user_mode+0x1d/0x40
do_syscall_64+0x48/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
If kvm_tdp_mmu_zap_all() skips a gfn/SPTE but that SPTE is then zapped by
kvm_tdp_mmu_put_root(), KVM triggers a use-after-free in the form of
marking a struct page as dirty/accessed after it has been put back on the
free list. This directly triggers a WARN due to encountering a page with
page_count() == 0, but it can also lead to data corruption and additional
errors in the kernel.
WARNING: CPU: 7 PID: 1995658 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:171
RIP: 0010:kvm_is_zone_device_pfn.part.0+0x9e/0xd0 [kvm]
Call Trace:
<TASK>
kvm_set_pfn_dirty+0x120/0x1d0 [kvm]
__handle_changed_spte+0x92e/0xca0 [kvm]
__handle_changed_spte+0x63c/0xca0 [kvm]
__handle_changed_spte+0x63c/0xca0 [kvm]
__handle_changed_spte+0x63c/0xca0 [kvm]
zap_gfn_range+0x549/0x620 [kvm]
kvm_tdp_mmu_put_root+0x1b6/0x270 [kvm]
mmu_free_root_page+0x219/0x2c0 [kvm]
kvm_mmu_free_roots+0x1b4/0x4e0 [kvm]
kvm_mmu_unload+0x1c/0xa0 [kvm]
kvm_arch_destroy_vm+0x1f2/0x5c0 [kvm]
kvm_put_kvm+0x3b1/0x8b0 [kvm]
kvm_vcpu_release+0x4e/0x70 [kvm]
__fput+0x1f7/0x8c0
task_work_run+0xf8/0x1a0
do_exit+0x97b/0x2230
do_group_exit+0xda/0x2a0
get_signal+0x3be/0x1e50
arch_do_signal_or_restart+0x244/0x17f0
exit_to_user_mode_prepare+0xcb/0x120
syscall_exit_to_user_mode+0x1d/0x40
do_syscall_64+0x4d/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
Note, the underlying bug existed even before commit 1af4a96025b3 ("KVM:
x86/mmu: Yield in TDU MMU iter even if no SPTES changed") moved calls to
tdp_mmu_iter_cond_resched() to the beginning of loops, as KVM could still
incorrectly advance past a top-level entry when yielding on a lower-level
entry. But with respect to leaking shadow pages, the bug was introduced
by yielding before processing the current gfn.
Alternatively, tdp_mmu_iter_cond_resched() could simply fall through, or
callers could jump to their "retry" label. The downside of that approach
is that tdp_mmu_iter_cond_resched() _must_ be called before anything else
in the loop, and there's no easy way to enfornce that requirement.
Ideally, KVM would handling the cond_resched() fully within the iterator
macro (the code is actually quite clean) and avoid this entire class of
bugs, but that is extremely difficult do wh
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Clear all QP fields if creation failed
rxe_qp_do_cleanup() relies on valid pointer values in QP for the properly
created ones, but in case rxe_qp_from_init() failed it was filled with
garbage and caused tot the following error.
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 12560 at lib/refcount.c:28 refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28
Modules linked in:
CPU: 1 PID: 12560 Comm: syz-executor.4 Not tainted 5.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28
Code: e9 db fe ff ff 48 89 df e8 2c c2 ea fd e9 8a fe ff ff e8 72 6a a7 fd 48 c7 c7 e0 b2 c1 89 c6 05 dc 3a e6 09 01 e8 ee 74 fb 04 <0f> 0b e9 af fe ff ff 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55
RSP: 0018:ffffc900097ceba8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff815bb075 RDI: fffff520012f9d67
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815b4eae R11: 0000000000000000 R12: ffff8880322a4800
R13: ffff8880322a4940 R14: ffff888033044e00 R15: 0000000000000000
FS: 00007f6eb2be3700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdbe5d41000 CR3: 000000001d181000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__refcount_sub_and_test include/linux/refcount.h:283 [inline]
__refcount_dec_and_test include/linux/refcount.h:315 [inline]
refcount_dec_and_test include/linux/refcount.h:333 [inline]
kref_put include/linux/kref.h:64 [inline]
rxe_qp_do_cleanup+0x96f/0xaf0 drivers/infiniband/sw/rxe/rxe_qp.c:805
execute_in_process_context+0x37/0x150 kernel/workqueue.c:3327
rxe_elem_release+0x9f/0x180 drivers/infiniband/sw/rxe/rxe_pool.c:391
kref_put include/linux/kref.h:65 [inline]
rxe_create_qp+0x2cd/0x310 drivers/infiniband/sw/rxe/rxe_verbs.c:425
_ib_create_qp drivers/infiniband/core/core_priv.h:331 [inline]
ib_create_named_qp+0x2ad/0x1370 drivers/infiniband/core/verbs.c:1231
ib_create_qp include/rdma/ib_verbs.h:3644 [inline]
create_mad_qp+0x177/0x2d0 drivers/infiniband/core/mad.c:2920
ib_mad_port_open drivers/infiniband/core/mad.c:3001 [inline]
ib_mad_init_device+0xd6f/0x1400 drivers/infiniband/core/mad.c:3092
add_client_context+0x405/0x5e0 drivers/infiniband/core/device.c:717
enable_device_and_get+0x1cd/0x3b0 drivers/infiniband/core/device.c:1331
ib_register_device drivers/infiniband/core/device.c:1413 [inline]
ib_register_device+0x7c7/0xa50 drivers/infiniband/core/device.c:1365
rxe_register_device+0x3d5/0x4a0 drivers/infiniband/sw/rxe/rxe_verbs.c:1147
rxe_add+0x12fe/0x16d0 drivers/infiniband/sw/rxe/rxe.c:247
rxe_net_add+0x8c/0xe0 drivers/infiniband/sw/rxe/rxe_net.c:503
rxe_newlink drivers/infiniband/sw/rxe/rxe.c:269 [inline]
rxe_newlink+0xb7/0xe0 drivers/infiniband/sw/rxe/rxe.c:250
nldev_newlink+0x30e/0x550 drivers/infiniband/core/nldev.c:1555
rdma_nl_rcv_msg+0x36d/0x690 drivers/infiniband/core/netlink.c:195
rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
rdma_nl_rcv+0x2ee/0x430 drivers/infiniband/core/netlink.c:259
netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
sock_sendmsg_nosec net/socket.c:654 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:674
____sys_sendmsg+0x6e8/0x810 net/socket.c:2350
___sys_sendmsg+0xf3/0x170 net/socket.c:2404
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2433
do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Stop looking for coalesced MMIO zones if the bus is destroyed
Abort the walk of coalesced MMIO zones if kvm_io_bus_unregister_dev()
fails to allocate memory for the new instance of the bus. If it can't
instantiate a new bus, unregister_dev() destroys all devices _except_ the
target device. But, it doesn't tell the caller that it obliterated the
bus and invoked the destructor for all devices that were on the bus. In
the coalesced MMIO case, this can result in a deleted list entry
dereference due to attempting to continue iterating on coalesced_zones
after future entries (in the walk) have been deleted.
Opportunistically add curly braces to the for-loop, which encompasses
many lines but sneaks by without braces due to the guts being a single
if statement. |
| In the Linux kernel, the following vulnerability has been resolved:
Drivers: hv: vmbus: Use after free in __vmbus_open()
The "open_info" variable is added to the &vmbus_connection.chn_msg_list,
but the error handling frees "open_info" without removing it from the
list. This will result in a use after free. First remove it from the
list, and then free it. |
| In the Linux kernel, the following vulnerability has been resolved:
ath10k: Fix a use after free in ath10k_htc_send_bundle
In ath10k_htc_send_bundle, the bundle_skb could be freed by
dev_kfree_skb_any(bundle_skb). But the bundle_skb is used later
by bundle_skb->len.
As skb_len = bundle_skb->len, my patch replaces bundle_skb->len to
skb_len after the bundle_skb was freed. |
| In the Linux kernel, the following vulnerability has been resolved:
net:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send
In emac_mac_tx_buf_send, it calls emac_tx_fill_tpd(..,skb,..).
If some error happens in emac_tx_fill_tpd(), the skb will be freed via
dev_kfree_skb(skb) in error branch of emac_tx_fill_tpd().
But the freed skb is still used via skb->len by netdev_sent_queue(,skb->len).
As i observed that emac_tx_fill_tpd() haven't modified the value of skb->len,
thus my patch assigns skb->len to 'len' before the possible free and
use 'len' instead of skb->len later. |
| In the Linux kernel, the following vulnerability has been resolved:
mm: memcontrol: slab: fix obtain a reference to a freeing memcg
Patch series "Use obj_cgroup APIs to charge kmem pages", v5.
Since Roman's series "The new cgroup slab memory controller" applied.
All slab objects are charged with the new APIs of obj_cgroup. The new
APIs introduce a struct obj_cgroup to charge slab objects. It prevents
long-living objects from pinning the original memory cgroup in the
memory. But there are still some corner objects (e.g. allocations
larger than order-1 page on SLUB) which are not charged with the new
APIs. Those objects (include the pages which are allocated from buddy
allocator directly) are charged as kmem pages which still hold a
reference to the memory cgroup.
E.g. We know that the kernel stack is charged as kmem pages because the
size of the kernel stack can be greater than 2 pages (e.g. 16KB on
x86_64 or arm64). If we create a thread (suppose the thread stack is
charged to memory cgroup A) and then move it from memory cgroup A to
memory cgroup B. Because the kernel stack of the thread hold a
reference to the memory cgroup A. The thread can pin the memory cgroup
A in the memory even if we remove the cgroup A. If we want to see this
scenario by using the following script. We can see that the system has
added 500 dying cgroups (This is not a real world issue, just a script
to show that the large kmallocs are charged as kmem pages which can pin
the memory cgroup in the memory).
#!/bin/bash
cat /proc/cgroups | grep memory
cd /sys/fs/cgroup/memory
echo 1 > memory.move_charge_at_immigrate
for i in range{1..500}
do
mkdir kmem_test
echo $$ > kmem_test/cgroup.procs
sleep 3600 &
echo $$ > cgroup.procs
echo `cat kmem_test/cgroup.procs` > cgroup.procs
rmdir kmem_test
done
cat /proc/cgroups | grep memory
This patchset aims to make those kmem pages to drop the reference to
memory cgroup by using the APIs of obj_cgroup. Finally, we can see that
the number of the dying cgroups will not increase if we run the above test
script.
This patch (of 7):
The rcu_read_lock/unlock only can guarantee that the memcg will not be
freed, but it cannot guarantee the success of css_get (which is in the
refill_stock when cached memcg changed) to memcg.
rcu_read_lock()
memcg = obj_cgroup_memcg(old)
__memcg_kmem_uncharge(memcg)
refill_stock(memcg)
if (stock->cached != memcg)
// css_get can change the ref counter from 0 back to 1.
css_get(&memcg->css)
rcu_read_unlock()
This fix is very like the commit:
eefbfa7fd678 ("mm: memcg/slab: fix use after free in obj_cgroup_charge")
Fix this by holding a reference to the memcg which is passed to the
__memcg_kmem_uncharge() before calling __memcg_kmem_uncharge(). |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: do asoc update earlier in sctp_sf_do_dupcook_a
There's a panic that occurs in a few of envs, the call trace is as below:
[] general protection fault, ... 0x29acd70f1000a: 0000 [#1] SMP PTI
[] RIP: 0010:sctp_ulpevent_notify_peer_addr_change+0x4b/0x1fa [sctp]
[] sctp_assoc_control_transport+0x1b9/0x210 [sctp]
[] sctp_do_8_2_transport_strike.isra.16+0x15c/0x220 [sctp]
[] sctp_cmd_interpreter.isra.21+0x1231/0x1a10 [sctp]
[] sctp_do_sm+0xc3/0x2a0 [sctp]
[] sctp_generate_timeout_event+0x81/0xf0 [sctp]
This is caused by a transport use-after-free issue. When processing a
duplicate COOKIE-ECHO chunk in sctp_sf_do_dupcook_a(), both COOKIE-ACK
and SHUTDOWN chunks are allocated with the transort from the new asoc.
However, later in the sideeffect machine, the old asoc is used to send
them out and old asoc's shutdown_last_sent_to is set to the transport
that SHUTDOWN chunk attached to in sctp_cmd_setup_t2(), which actually
belongs to the new asoc. After the new_asoc is freed and the old asoc
T2 timeout, the old asoc's shutdown_last_sent_to that is already freed
would be accessed in sctp_sf_t2_timer_expire().
Thanks Alexander and Jere for helping dig into this issue.
To fix it, this patch is to do the asoc update first, then allocate
the COOKIE-ACK and SHUTDOWN chunks with the 'updated' old asoc. This
would make more sense, as a chunk from an asoc shouldn't be sent out
with another asoc. We had fixed quite a few issues caused by this. |
| In the Linux kernel, the following vulnerability has been resolved:
net: qrtr: Avoid potential use after free in MHI send
It is possible that the MHI ul_callback will be invoked immediately
following the queueing of the skb for transmission, leading to the
callback decrementing the refcount of the associated sk and freeing the
skb.
As such the dereference of skb and the increment of the sk refcount must
happen before the skb is queued, to avoid the skb to be used after free
and potentially the sk to drop its last refcount.. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix crash in qla2xxx_mqueuecommand()
RIP: 0010:kmem_cache_free+0xfa/0x1b0
Call Trace:
qla2xxx_mqueuecommand+0x2b5/0x2c0 [qla2xxx]
scsi_queue_rq+0x5e2/0xa40
__blk_mq_try_issue_directly+0x128/0x1d0
blk_mq_request_issue_directly+0x4e/0xb0
Fix incorrect call to free srb in qla2xxx_mqueuecommand(), as srb is now
allocated by upper layers. This fixes smatch warning of srb unintended
free. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix race between transaction aborts and fsyncs leading to use-after-free
There is a race between a task aborting a transaction during a commit,
a task doing an fsync and the transaction kthread, which leads to an
use-after-free of the log root tree. When this happens, it results in a
stack trace like the following:
BTRFS info (device dm-0): forced readonly
BTRFS warning (device dm-0): Skipping commit of aborted transaction.
BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure
BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5)
BTRFS warning (device dm-0): Skipping commit of aborted transaction.
BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10
BTRFS error (device dm-0): error writing primary super block to device 1
BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10
BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10
BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10
BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers)
BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure
general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:__mutex_lock+0x139/0xa40
Code: c0 74 19 (...)
RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202
RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002
RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000
R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040
R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358
FS: 00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
? __btrfs_handle_fs_error+0xde/0x146 [btrfs]
? btrfs_sync_log+0x7c1/0xf20 [btrfs]
? btrfs_sync_log+0x7c1/0xf20 [btrfs]
btrfs_sync_log+0x7c1/0xf20 [btrfs]
btrfs_sync_file+0x40c/0x580 [btrfs]
do_fsync+0x38/0x70
__x64_sys_fsync+0x10/0x20
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fa9142a55c3
Code: 8b 15 09 (...)
RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3
RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005
RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340
R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0
Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...)
---[ end trace ee2f1b19327d791d ]---
The steps that lead to this crash are the following:
1) We are at transaction N;
2) We have two tasks with a transaction handle attached to transaction N.
Task A and Task B. Task B is doing an fsync;
3) Task B is at btrfs_sync_log(), and has saved fs_info->log_root_tree
into a local variable named 'log_root_tree' at the top of
btrfs_sync_log(). Task B is about to call write_all_supers(), but
before that...
4) Task A calls btrfs_commit_transaction(), and after it sets the
transaction state to TRANS_STATE_COMMIT_START, an error happens before
it w
---truncated--- |
