| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
nvme-fc: do not wait in vain when unloading module
The module exit path has race between deleting all controllers and
freeing 'left over IDs'. To prevent double free a synchronization
between nvme_delete_ctrl and ida_destroy has been added by the initial
commit.
There is some logic around trying to prevent from hanging forever in
wait_for_completion, though it does not handling all cases. E.g.
blktests is able to reproduce the situation where the module unload
hangs forever.
If we completely rely on the cleanup code executed from the
nvme_delete_ctrl path, all IDs will be freed eventually. This makes
calling ida_destroy unnecessary. We only have to ensure that all
nvme_delete_ctrl code has been executed before we leave
nvme_fc_exit_module. This is done by flushing the nvme_delete_wq
workqueue.
While at it, remove the unused nvme_fc_wq workqueue too. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: fix race condition on enabling fast-xmit
fast-xmit must only be enabled after the sta has been uploaded to the driver,
otherwise it could end up passing the not-yet-uploaded sta via drv_tx calls
to the driver, leading to potential crashes because of uninitialized drv_priv
data.
Add a missing sta->uploaded check and re-check fast xmit after inserting a sta. |
| In the Linux kernel, the following vulnerability has been resolved:
blk-mq: fix IO hang from sbitmap wakeup race
In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered
with the following blk_mq_get_driver_tag() in case of getting driver
tag failure.
Then in __sbitmap_queue_wake_up(), waitqueue_active() may not observe
the added waiter in blk_mq_mark_tag_wait() and wake up nothing, meantime
blk_mq_mark_tag_wait() can't get driver tag successfully.
This issue can be reproduced by running the following test in loop, and
fio hang can be observed in < 30min when running it on my test VM
in laptop.
modprobe -r scsi_debug
modprobe scsi_debug delay=0 dev_size_mb=4096 max_queue=1 host_max_queue=1 submit_queues=4
dev=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter*/host*/target*/*/block/* | head -1 | xargs basename`
fio --filename=/dev/"$dev" --direct=1 --rw=randrw --bs=4k --iodepth=1 \
--runtime=100 --numjobs=40 --time_based --name=test \
--ioengine=libaio
Fix the issue by adding one explicit barrier in blk_mq_mark_tag_wait(), which
is just fine in case of running out of tag. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: don't abort filesystem when attempting to snapshot deleted subvolume
If the source file descriptor to the snapshot ioctl refers to a deleted
subvolume, we get the following abort:
BTRFS: Transaction aborted (error -2)
WARNING: CPU: 0 PID: 833 at fs/btrfs/transaction.c:1875 create_pending_snapshot+0x1040/0x1190 [btrfs]
Modules linked in: pata_acpi btrfs ata_piix libata scsi_mod virtio_net blake2b_generic xor net_failover virtio_rng failover scsi_common rng_core raid6_pq libcrc32c
CPU: 0 PID: 833 Comm: t_snapshot_dele Not tainted 6.7.0-rc6 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014
RIP: 0010:create_pending_snapshot+0x1040/0x1190 [btrfs]
RSP: 0018:ffffa09c01337af8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff9982053e7c78 RCX: 0000000000000027
RDX: ffff99827dc20848 RSI: 0000000000000001 RDI: ffff99827dc20840
RBP: ffffa09c01337c00 R08: 0000000000000000 R09: ffffa09c01337998
R10: 0000000000000003 R11: ffffffffb96da248 R12: fffffffffffffffe
R13: ffff99820535bb28 R14: ffff99820b7bd000 R15: ffff99820381ea80
FS: 00007fe20aadabc0(0000) GS:ffff99827dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559a120b502f CR3: 00000000055b6000 CR4: 00000000000006f0
Call Trace:
<TASK>
? create_pending_snapshot+0x1040/0x1190 [btrfs]
? __warn+0x81/0x130
? create_pending_snapshot+0x1040/0x1190 [btrfs]
? report_bug+0x171/0x1a0
? handle_bug+0x3a/0x70
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? create_pending_snapshot+0x1040/0x1190 [btrfs]
? create_pending_snapshot+0x1040/0x1190 [btrfs]
create_pending_snapshots+0x92/0xc0 [btrfs]
btrfs_commit_transaction+0x66b/0xf40 [btrfs]
btrfs_mksubvol+0x301/0x4d0 [btrfs]
btrfs_mksnapshot+0x80/0xb0 [btrfs]
__btrfs_ioctl_snap_create+0x1c2/0x1d0 [btrfs]
btrfs_ioctl_snap_create_v2+0xc4/0x150 [btrfs]
btrfs_ioctl+0x8a6/0x2650 [btrfs]
? kmem_cache_free+0x22/0x340
? do_sys_openat2+0x97/0xe0
__x64_sys_ioctl+0x97/0xd0
do_syscall_64+0x46/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
RIP: 0033:0x7fe20abe83af
RSP: 002b:00007ffe6eff1360 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fe20abe83af
RDX: 00007ffe6eff23c0 RSI: 0000000050009417 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 00007fe20ad16cd0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe6eff13c0 R14: 00007fe20ad45000 R15: 0000559a120b6d58
</TASK>
---[ end trace 0000000000000000 ]---
BTRFS: error (device vdc: state A) in create_pending_snapshot:1875: errno=-2 No such entry
BTRFS info (device vdc: state EA): forced readonly
BTRFS warning (device vdc: state EA): Skipping commit of aborted transaction.
BTRFS: error (device vdc: state EA) in cleanup_transaction:2055: errno=-2 No such entry
This happens because create_pending_snapshot() initializes the new root
item as a copy of the source root item. This includes the refs field,
which is 0 for a deleted subvolume. The call to btrfs_insert_root()
therefore inserts a root with refs == 0. btrfs_get_new_fs_root() then
finds the root and returns -ENOENT if refs == 0, which causes
create_pending_snapshot() to abort.
Fix it by checking the source root's refs before attempting the
snapshot, but after locking subvol_sem to avoid racing with deletion. |
| In the Linux kernel, the following vulnerability has been resolved:
spi: sun6i: fix race between DMA RX transfer completion and RX FIFO drain
Previously the transfer complete IRQ immediately drained to RX FIFO to
read any data remaining in FIFO to the RX buffer. This behaviour is
correct when dealing with SPI in interrupt mode. However in DMA mode the
transfer complete interrupt still fires as soon as all bytes to be
transferred have been stored in the FIFO. At that point data in the FIFO
still needs to be picked up by the DMA engine. Thus the drain procedure
and DMA engine end up racing to read from RX FIFO, corrupting any data
read. Additionally the RX buffer pointer is never adjusted according to
DMA progress in DMA mode, thus calling the RX FIFO drain procedure in DMA
mode is a bug.
Fix corruptions in DMA RX mode by draining RX FIFO only in interrupt mode.
Also wait for completion of RX DMA when in DMA mode before returning to
ensure all data has been copied to the supplied memory buffer. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: logitech-hidpp: Fix kernel crash on receiver USB disconnect
hidpp_connect_event() has *four* time-of-check vs time-of-use (TOCTOU)
races when it races with itself.
hidpp_connect_event() primarily runs from a workqueue but it also runs
on probe() and if a "device-connected" packet is received by the hw
when the thread running hidpp_connect_event() from probe() is waiting on
the hw, then a second thread running hidpp_connect_event() will be
started from the workqueue.
This opens the following races (note the below code is simplified):
1. Retrieving + printing the protocol (harmless race):
if (!hidpp->protocol_major) {
hidpp_root_get_protocol_version()
hidpp->protocol_major = response.rap.params[0];
}
We can actually see this race hit in the dmesg in the abrt output
attached to rhbz#2227968:
[ 3064.624215] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.
[ 3064.658184] logitech-hidpp-device 0003:046D:4071.0049: HID++ 4.5 device connected.
Testing with extra logging added has shown that after this the 2 threads
take turn grabbing the hw access mutex (send_mutex) so they ping-pong
through all the other TOCTOU cases managing to hit all of them:
2. Updating the name to the HIDPP name (harmless race):
if (hidpp->name == hdev->name) {
...
hidpp->name = new_name;
}
3. Initializing the power_supply class for the battery (problematic!):
hidpp_initialize_battery()
{
if (hidpp->battery.ps)
return 0;
probe_battery(); /* Blocks, threads take turns executing this */
hidpp->battery.desc.properties =
devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
hidpp->battery.ps =
devm_power_supply_register(&hidpp->hid_dev->dev,
&hidpp->battery.desc, cfg);
}
4. Creating delayed input_device (potentially problematic):
if (hidpp->delayed_input)
return;
hidpp->delayed_input = hidpp_allocate_input(hdev);
The really big problem here is 3. Hitting the race leads to the following
sequence:
hidpp->battery.desc.properties =
devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
hidpp->battery.ps =
devm_power_supply_register(&hidpp->hid_dev->dev,
&hidpp->battery.desc, cfg);
...
hidpp->battery.desc.properties =
devm_kmemdup(dev, hidpp_battery_props, cnt, GFP_KERNEL);
hidpp->battery.ps =
devm_power_supply_register(&hidpp->hid_dev->dev,
&hidpp->battery.desc, cfg);
So now we have registered 2 power supplies for the same battery,
which looks a bit weird from userspace's pov but this is not even
the really big problem.
Notice how:
1. This is all devm-maganaged
2. The hidpp->battery.desc struct is shared between the 2 power supplies
3. hidpp->battery.desc.properties points to the result from the second
devm_kmemdup()
This causes a use after free scenario on USB disconnect of the receiver:
1. The last registered power supply class device gets unregistered
2. The memory from the last devm_kmemdup() call gets freed,
hidpp->battery.desc.properties now points to freed memory
3. The first registered power supply class device gets unregistered,
this involves sending a remove uevent to userspace which invokes
power_supply_uevent() to fill the uevent data
4. power_supply_uevent() uses hidpp->battery.desc.properties which
now points to freed memory leading to backtraces like this one:
Sep 22 20:01:35 eric kernel: BUG: unable to handle page fault for address: ffffb2140e017f08
...
Sep 22 20:01:35 eric kernel: Workqueue: usb_hub_wq hub_event
Sep 22 20:01:35 eric kernel: RIP: 0010:power_supply_uevent+0xee/0x1d0
...
Sep 22 20:01:35 eric kernel: ? asm_exc_page_fault+0x26/0x30
Sep 22 20:01:35 eric kernel: ? power_supply_uevent+0xee/0x1d0
Sep 22 20:01:35 eric kernel: ? power_supply_uevent+0x10d/0x1d0
Sep 22 20:01:35 eric kernel: dev_uevent+0x10f/0x2d0
Sep 22 20:01:35 eric kernel: kobject_uevent_env+0x291/0x680
Sep 22 20:01:35 eric kernel:
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: Fix race of buffer access at PCM OSS layer
The PCM OSS layer tries to clear the buffer with the silence data at
initialization (or reconfiguration) of a stream with the explicit call
of snd_pcm_format_set_silence() with runtime->dma_area. But this may
lead to a UAF because the accessed runtime->dma_area might be freed
concurrently, as it's performed outside the PCM ops.
For avoiding it, move the code into the PCM core and perform it inside
the buffer access lock, so that it won't be changed during the
operation. |
| In the Linux kernel, the following vulnerability has been resolved:
virtio_ring: Fix data race by tagging event_triggered as racy for KCSAN
syzbot reports a data-race when accessing the event_triggered, here is the
simplified stack when the issue occurred:
==================================================================
BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_enable_cb_delayed
write to 0xffff8881025bc452 of 1 bytes by task 3288 on cpu 0:
virtqueue_enable_cb_delayed+0x42/0x3c0 drivers/virtio/virtio_ring.c:2653
start_xmit+0x230/0x1310 drivers/net/virtio_net.c:3264
__netdev_start_xmit include/linux/netdevice.h:5151 [inline]
netdev_start_xmit include/linux/netdevice.h:5160 [inline]
xmit_one net/core/dev.c:3800 [inline]
read to 0xffff8881025bc452 of 1 bytes by interrupt on cpu 1:
virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:880 [inline]
virtqueue_disable_cb+0x92/0x180 drivers/virtio/virtio_ring.c:2566
skb_xmit_done+0x5f/0x140 drivers/net/virtio_net.c:777
vring_interrupt+0x161/0x190 drivers/virtio/virtio_ring.c:2715
__handle_irq_event_percpu+0x95/0x490 kernel/irq/handle.c:158
handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
value changed: 0x01 -> 0x00
==================================================================
When the data race occurs, the function virtqueue_enable_cb_delayed() sets
event_triggered to false, and virtqueue_disable_cb_split/packed() reads it
as false due to the race condition. Since event_triggered is an unreliable
hint used for optimization, this should only cause the driver temporarily
suggest that the device not send an interrupt notification when the event
index is used.
Fix this KCSAN reported data-race issue by explicitly tagging the access as
data_racy. |
| 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 [nfs_layout_nfsv41_files e3a4187f18ae8a27b630f9feae6831b584a9360a]
[ 57.202765] pnfs_generic_pg_writepages+0xbe/0x230 [nfsv4 c716d88496ded0ea6d289bbea684fa996f9b57a9]
[ 57.202788] __nfs_pageio_add_request+0x3fd/0x520 [nfs 6c976fa593a7c2976f5a0aeb4965514a828e6902]
[ 57.202813] nfs_pageio_add_request+0x18b/0x390 [nfs 6c976fa593a7c2976f5a0aeb4965514a828e6902]
[ 57.202831] nfs_do_writepage+0x116/0x1e0 [nfs 6c976fa593a7c2976f5a0aeb4965514a828e6902]
[ 57.202849] nfs_writepages_callback+0x13/0x30 [nfs 6c976fa593a7c2976f5a0aeb4965514a828e6902]
[ 57.202866] write_cache_pages+0x265/0x450
[ 57.202870] ? __pfx_nfs_writepages_callback+0x10/0x10 [nfs 6c976fa593a7c2976f5a0aeb4965514a828e6902]
[ 57.202891] nfs_writepages+0x141/0x230 [nfs 6c976fa593a7c2976f5a0aeb4965514a828e6902]
[ 57.202913] do_writepages+0xd2/0x230
[ 57.202917] ? filemap_fdatawrite_wbc+0x5c/0x80
[ 57.202921] filemap_fdatawrite_wbc+0x67/0x80
[ 57.202924] filemap_write_and_wait_range+0xd9/0x170
[ 57.202930] nfs_wb_all+0x49/0x180 [nfs 6c976fa593a7c2976f5a0aeb4965514a828e6902]
[ 57.202947] nfs4_file_flush+0x72/0xb0 [nfsv4 c716d88496ded0ea6d289bbea684fa996f9b57a9]
[ 57.202969] __se_sys_close+0x46/0xd0
[ 57.202972] do_syscall_64+0x68/0x100
[ 57.202975] ? do_syscall_64+0x77/0x100
[ 57.202976] ? do_syscall_64+0x77/0x100
[ 57.202979] entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 57.202982] RIP: 0033:0x7fe2b12e4a94
[ 57.202985] Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 80 3d d5 18 0e 00 00 74 13 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 44 c3 0f 1f 00 48 83 ec 18 89 7c 24 0c e8 c3
[ 57.202987] RSP: 002b:00007ffe857ddb38 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
[ 57.202989] RAX: ffffffffffffffda RBX: 00007ffe857dfd68 RCX: 00007fe2b12e4a94
[ 57.202991] RDX: 0000000000002000 RSI: 00007ffe857ddc40 RDI: 0000000000000003
[ 57.202992] RBP: 00007ffe857dfc50 R08: 7fffffffffffffff R09: 0000000065650f49
[ 57.202993] R10: 00007f
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
eeprom: at24: fix memory corruption race condition
If the eeprom is not accessible, an nvmem device will be registered, the
read will fail, and the device will be torn down. If another driver
accesses the nvmem device after the teardown, it will reference
invalid memory.
Move the failure point before registering the nvmem device. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSv4/pNFS: Fix a race to wake on NFS_LAYOUT_DRAIN
We found a few different systems hung up in writeback waiting on the same
page lock, and one task waiting on the NFS_LAYOUT_DRAIN bit in
pnfs_update_layout(), however the pnfs_layout_hdr's plh_outstanding count
was zero.
It seems most likely that this is another race between the waiter and waker
similar to commit ed0172af5d6f ("SUNRPC: Fix a race to wake a sync task").
Fix it up by applying the advised barrier. |
| In the Linux kernel, the following vulnerability has been resolved:
i40e: fix vf may be used uninitialized in this function warning
To fix the regression introduced by commit 52424f974bc5, which causes
servers hang in very hard to reproduce conditions with resets races.
Using two sources for the information is the root cause.
In this function before the fix bumping v didn't mean bumping vf
pointer. But the code used this variables interchangeably, so stale vf
could point to different/not intended vf.
Remove redundant "v" variable and iterate via single VF pointer across
whole function instead to guarantee VF pointer validity. |
| In the Linux kernel, the following vulnerability has been resolved:
af_unix: Fix garbage collector racing against connect()
Garbage collector does not take into account the risk of embryo getting
enqueued during the garbage collection. If such embryo has a peer that
carries SCM_RIGHTS, two consecutive passes of scan_children() may see a
different set of children. Leading to an incorrectly elevated inflight
count, and then a dangling pointer within the gc_inflight_list.
sockets are AF_UNIX/SOCK_STREAM
S is an unconnected socket
L is a listening in-flight socket bound to addr, not in fdtable
V's fd will be passed via sendmsg(), gets inflight count bumped
connect(S, addr) sendmsg(S, [V]); close(V) __unix_gc()
---------------- ------------------------- -----------
NS = unix_create1()
skb1 = sock_wmalloc(NS)
L = unix_find_other(addr)
unix_state_lock(L)
unix_peer(S) = NS
// V count=1 inflight=0
NS = unix_peer(S)
skb2 = sock_alloc()
skb_queue_tail(NS, skb2[V])
// V became in-flight
// V count=2 inflight=1
close(V)
// V count=1 inflight=1
// GC candidate condition met
for u in gc_inflight_list:
if (total_refs == inflight_refs)
add u to gc_candidates
// gc_candidates={L, V}
for u in gc_candidates:
scan_children(u, dec_inflight)
// embryo (skb1) was not
// reachable from L yet, so V's
// inflight remains unchanged
__skb_queue_tail(L, skb1)
unix_state_unlock(L)
for u in gc_candidates:
if (u.inflight)
scan_children(u, inc_inflight_move_tail)
// V count=1 inflight=2 (!)
If there is a GC-candidate listening socket, lock/unlock its state. This
makes GC wait until the end of any ongoing connect() to that socket. After
flipping the lock, a possibly SCM-laden embryo is already enqueued. And if
there is another embryo coming, it can not possibly carry SCM_RIGHTS. At
this point, unix_inflight() can not happen because unix_gc_lock is already
taken. Inflight graph remains unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath9k: delay all of ath9k_wmi_event_tasklet() until init is complete
The ath9k_wmi_event_tasklet() used in ath9k_htc assumes that all the data
structures have been fully initialised by the time it runs. However, because of
the order in which things are initialised, this is not guaranteed to be the
case, because the device is exposed to the USB subsystem before the ath9k driver
initialisation is completed.
We already committed a partial fix for this in commit:
8b3046abc99e ("ath9k_htc: fix NULL pointer dereference at ath9k_htc_tx_get_packet()")
However, that commit only aborted the WMI_TXSTATUS_EVENTID command in the event
tasklet, pairing it with an "initialisation complete" bit in the TX struct. It
seems syzbot managed to trigger the race for one of the other commands as well,
so let's just move the existing synchronisation bit to cover the whole
tasklet (setting it at the end of ath9k_htc_probe_device() instead of inside
ath9k_tx_init()). |
| In the Linux kernel, the following vulnerability has been resolved:
netrom: Fix data-races around sysctl_net_busy_read
We need to protect the reader reading the sysctl value because the
value can be changed concurrently. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_qfq: Fix race condition on qfq_aggregate
A race condition can occur when 'agg' is modified in qfq_change_agg
(called during qfq_enqueue) while other threads access it
concurrently. For example, qfq_dump_class may trigger a NULL
dereference, and qfq_delete_class may cause a use-after-free.
This patch addresses the issue by:
1. Moved qfq_destroy_class into the critical section.
2. Added sch_tree_lock protection to qfq_dump_class and
qfq_dump_class_stats. |
| In the Linux kernel, the following vulnerability has been resolved:
interconnect: Don't access req_list while it's being manipulated
The icc_lock mutex was split into separate icc_lock and icc_bw_lock
mutexes in [1] to avoid lockdep splats. However, this didn't adequately
protect access to icc_node::req_list.
The icc_set_bw() function will eventually iterate over req_list while
only holding icc_bw_lock, but req_list can be modified while only
holding icc_lock. This causes races between icc_set_bw(), of_icc_get(),
and icc_put().
Example A:
CPU0 CPU1
---- ----
icc_set_bw(path_a)
mutex_lock(&icc_bw_lock);
icc_put(path_b)
mutex_lock(&icc_lock);
aggregate_requests()
hlist_for_each_entry(r, ...
hlist_del(...
<r = invalid pointer>
Example B:
CPU0 CPU1
---- ----
icc_set_bw(path_a)
mutex_lock(&icc_bw_lock);
path_b = of_icc_get()
of_icc_get_by_index()
mutex_lock(&icc_lock);
path_find()
path_init()
aggregate_requests()
hlist_for_each_entry(r, ...
hlist_add_head(...
<r = invalid pointer>
Fix this by ensuring icc_bw_lock is always held before manipulating
icc_node::req_list. The additional places icc_bw_lock is held don't
perform any memory allocations, so we should still be safe from the
original lockdep splats that motivated the separate locks.
[1] commit af42269c3523 ("interconnect: Fix locking for runpm vs reclaim") |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix warning in ext4_iomap_begin as race between bmap and write
We got issue as follows:
------------[ cut here ]------------
WARNING: CPU: 3 PID: 9310 at fs/ext4/inode.c:3441 ext4_iomap_begin+0x182/0x5d0
RIP: 0010:ext4_iomap_begin+0x182/0x5d0
RSP: 0018:ffff88812460fa08 EFLAGS: 00010293
RAX: ffff88811f168000 RBX: 0000000000000000 RCX: ffffffff97793c12
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: ffff88812c669160 R08: ffff88811f168000 R09: ffffed10258cd20f
R10: ffff88812c669077 R11: ffffed10258cd20e R12: 0000000000000001
R13: 00000000000000a4 R14: 000000000000000c R15: ffff88812c6691ee
FS: 00007fd0d6ff3740(0000) GS:ffff8883af180000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0d6dda290 CR3: 0000000104a62000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
iomap_apply+0x119/0x570
iomap_bmap+0x124/0x150
ext4_bmap+0x14f/0x250
bmap+0x55/0x80
do_vfs_ioctl+0x952/0xbd0
__x64_sys_ioctl+0xc6/0x170
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Above issue may happen as follows:
bmap write
bmap
ext4_bmap
iomap_bmap
ext4_iomap_begin
ext4_file_write_iter
ext4_buffered_write_iter
generic_perform_write
ext4_da_write_begin
ext4_da_write_inline_data_begin
ext4_prepare_inline_data
ext4_create_inline_data
ext4_set_inode_flag(inode,
EXT4_INODE_INLINE_DATA);
if (WARN_ON_ONCE(ext4_has_inline_data(inode))) ->trigger bug_on
To solved above issue hold inode lock in ext4_bamp. |
| In the Linux kernel, the following vulnerability has been resolved:
binder: fix UAF of ref->proc caused by race condition
A transaction of type BINDER_TYPE_WEAK_HANDLE can fail to increment the
reference for a node. In this case, the target proc normally releases
the failed reference upon close as expected. However, if the target is
dying in parallel the call will race with binder_deferred_release(), so
the target could have released all of its references by now leaving the
cleanup of the new failed reference unhandled.
The transaction then ends and the target proc gets released making the
ref->proc now a dangling pointer. Later on, ref->node is closed and we
attempt to take spin_lock(&ref->proc->inner_lock), which leads to the
use-after-free bug reported below. Let's fix this by cleaning up the
failed reference on the spot instead of relying on the target to do so.
==================================================================
BUG: KASAN: use-after-free in _raw_spin_lock+0xa8/0x150
Write of size 4 at addr ffff5ca207094238 by task kworker/1:0/590
CPU: 1 PID: 590 Comm: kworker/1:0 Not tainted 5.19.0-rc8 #10
Hardware name: linux,dummy-virt (DT)
Workqueue: events binder_deferred_func
Call trace:
dump_backtrace.part.0+0x1d0/0x1e0
show_stack+0x18/0x70
dump_stack_lvl+0x68/0x84
print_report+0x2e4/0x61c
kasan_report+0xa4/0x110
kasan_check_range+0xfc/0x1a4
__kasan_check_write+0x3c/0x50
_raw_spin_lock+0xa8/0x150
binder_deferred_func+0x5e0/0x9b0
process_one_work+0x38c/0x5f0
worker_thread+0x9c/0x694
kthread+0x188/0x190
ret_from_fork+0x10/0x20 |
| In the Linux kernel, the following vulnerability has been resolved:
dm ioctl: fix misbehavior if list_versions races with module loading
__list_versions will first estimate the required space using the
"dm_target_iterate(list_version_get_needed, &needed)" call and then will
fill the space using the "dm_target_iterate(list_version_get_info,
&iter_info)" call. Each of these calls locks the targets using the
"down_read(&_lock)" and "up_read(&_lock)" calls, however between the first
and second "dm_target_iterate" there is no lock held and the target
modules can be loaded at this point, so the second "dm_target_iterate"
call may need more space than what was the first "dm_target_iterate"
returned.
The code tries to handle this overflow (see the beginning of
list_version_get_info), however this handling is incorrect.
The code sets "param->data_size = param->data_start + needed" and
"iter_info.end = (char *)vers+len" - "needed" is the size returned by the
first dm_target_iterate call; "len" is the size of the buffer allocated by
userspace.
"len" may be greater than "needed"; in this case, the code will write up
to "len" bytes into the buffer, however param->data_size is set to
"needed", so it may write data past the param->data_size value. The ioctl
interface copies only up to param->data_size into userspace, thus part of
the result will be truncated.
Fix this bug by setting "iter_info.end = (char *)vers + needed;" - this
guarantees that the second "dm_target_iterate" call will write only up to
the "needed" buffer and it will exit with "DM_BUFFER_FULL_FLAG" if it
overflows the "needed" space - in this case, userspace will allocate a
larger buffer and retry.
Note that there is also a bug in list_version_get_needed - we need to add
"strlen(tt->name) + 1" to the needed size, not "strlen(tt->name)". |
