In the Linux kernel, the following vulnerability has been resolved:
x86/mce: Work around an erratum on fast string copy instructions
A rare kernel panic scenario can happen when the following conditions
are met due to an erratum on fast string copy instructions:
1) An uncorrected error.
2) That error must be in first cache line of a page.
3) Kernel must execute page_copy from the page immediately before that
page.
The fast string copy instructions ("REP; MOVS*") could consume an
uncorrectable memory error in the cache line _right after_ the desired
region to copy and raise an MCE.
Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string
copy and will avoid such spurious machine checks. However, that is less
preferable due to the permanent performance impact. Considering memory
poison is rare, it's desirable to keep fast string copy enabled until an
MCE is seen.
Intel has confirmed the following:
1. The CPU erratum of fast string copy only applies to Skylake,
Cascade Lake and Cooper Lake generations.
Directly return from the MCE handler:
2. Will result in complete execution of the "REP; MOVS*" with no data
loss or corruption.
3. Will not result in another MCE firing on the next poisoned cache line
due to "REP; MOVS*".
4. Will resume execution from a correct point in code.
5. Will result in the same instruction that triggered the MCE firing a
second MCE immediately for any other software recoverable data fetch
errors.
6. Is not safe without disabling the fast string copy, as the next fast
string copy of the same buffer on the same CPU would result in a PANIC
MCE.
This should mitigate the erratum completely with the only caveat that
the fast string copy is disabled on the affected hyper thread thus
performance degradation.
This is still better than the OS crashing on MCEs raised on an
irrelevant process due to "REP; MOVS*' accesses in a kernel context,
e.g., copy_page.
Injected errors on 1st cache line of 8 anonymous pages of process
'proc1' and observed MCE consumption from 'proc2' with no panic
(directly returned).
Without the fix, the host panicked within a few minutes on a
random 'proc2' process due to kernel access from copy_page.
[ bp: Fix comment style + touch ups, zap an unlikely(), improve the
quirk function's readability. ]
In the Linux kernel, the following vulnerability has been resolved:
drm/sprd: fix potential NULL dereference
'drm' could be null in sprd_drm_shutdown, and drm_warn maybe dereference
it, remove this warning log.
v1 -> v2:
- Split checking platform_get_resource() return value to a separate patch
- Use dev_warn() instead of removing the warning log
In the Linux kernel, the following vulnerability has been resolved:
scsi: mpi3mr: Fix memory leaks
Fix memory leaks related to operational reply queue's memory segments which
are not getting freed while unloading the driver.
In the Linux kernel, the following vulnerability has been resolved:
staging: vchiq_arm: Avoid NULL ptr deref in vchiq_dump_platform_instances
vchiq_get_state() can return a NULL pointer. So handle this cases and
avoid a NULL pointer derefence in vchiq_dump_platform_instances.
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix memory leak in ceph_readdir when note_last_dentry returns error
Reset the last_readdir at the same time, and add a comment explaining
why we don't free last_readdir when dir_emit returns false.
In the Linux kernel, the following vulnerability has been resolved:
clk: mediatek: Fix memory leaks on probe
Handle the error branches to free memory where required.
Addresses-Coverity-ID: 1491825 ("Resource leak")
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: revisit gc autotuning
as of commit 4608fdfc07e1
("netfilter: conntrack: collect all entries in one cycle")
conntrack gc was changed to run every 2 minutes.
On systems where conntrack hash table is set to large value, most evictions
happen from gc worker rather than the packet path due to hash table
distribution.
This causes netlink event overflows when events are collected.
This change collects average expiry of scanned entries and
reschedules to the average remaining value, within 1 to 60 second interval.
To avoid event overflows, reschedule after each bucket and add a
limit for both run time and number of evictions per run.
If more entries have to be evicted, reschedule and restart 1 jiffy
into the future.
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: Fix use after free in hci_send_acl
This fixes the following trace caused by receiving
HCI_EV_DISCONN_PHY_LINK_COMPLETE which does call hci_conn_del without
first checking if conn->type is in fact AMP_LINK and in case it is
do properly cleanup upper layers with hci_disconn_cfm:
==================================================================
BUG: KASAN: use-after-free in hci_send_acl+0xaba/0xc50
Read of size 8 at addr ffff88800e404818 by task bluetoothd/142
CPU: 0 PID: 142 Comm: bluetoothd Not tainted
5.17.0-rc5-00006-gda4022eeac1a #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x45/0x59
print_address_description.constprop.0+0x1f/0x150
kasan_report.cold+0x7f/0x11b
hci_send_acl+0xaba/0xc50
l2cap_do_send+0x23f/0x3d0
l2cap_chan_send+0xc06/0x2cc0
l2cap_sock_sendmsg+0x201/0x2b0
sock_sendmsg+0xdc/0x110
sock_write_iter+0x20f/0x370
do_iter_readv_writev+0x343/0x690
do_iter_write+0x132/0x640
vfs_writev+0x198/0x570
do_writev+0x202/0x280
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RSP: 002b:00007ffce8a099b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3
0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 14 00 00 00 0f 05
<48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
RDX: 0000000000000001 RSI: 00007ffce8a099e0 RDI: 0000000000000015
RAX: ffffffffffffffda RBX: 00007ffce8a099e0 RCX: 00007f788fc3cf77
R10: 00007ffce8af7080 R11: 0000000000000246 R12: 000055e4ccf75580
RBP: 0000000000000015 R08: 0000000000000002 R09: 0000000000000001
</TASK>
R13: 000055e4ccf754a0 R14: 000055e4ccf75cd0 R15: 000055e4ccf4a6b0
Allocated by task 45:
kasan_save_stack+0x1e/0x40
__kasan_kmalloc+0x81/0xa0
hci_chan_create+0x9a/0x2f0
l2cap_conn_add.part.0+0x1a/0xdc0
l2cap_connect_cfm+0x236/0x1000
le_conn_complete_evt+0x15a7/0x1db0
hci_le_conn_complete_evt+0x226/0x2c0
hci_le_meta_evt+0x247/0x450
hci_event_packet+0x61b/0xe90
hci_rx_work+0x4d5/0xc50
process_one_work+0x8fb/0x15a0
worker_thread+0x576/0x1240
kthread+0x29d/0x340
ret_from_fork+0x1f/0x30
Freed by task 45:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_set_free_info+0x20/0x30
__kasan_slab_free+0xfb/0x130
kfree+0xac/0x350
hci_conn_cleanup+0x101/0x6a0
hci_conn_del+0x27e/0x6c0
hci_disconn_phylink_complete_evt+0xe0/0x120
hci_event_packet+0x812/0xe90
hci_rx_work+0x4d5/0xc50
process_one_work+0x8fb/0x15a0
worker_thread+0x576/0x1240
kthread+0x29d/0x340
ret_from_fork+0x1f/0x30
The buggy address belongs to the object at ffff88800c0f0500
The buggy address is located 24 bytes inside of
which belongs to the cache kmalloc-128 of size 128
The buggy address belongs to the page:
128-byte region [ffff88800c0f0500, ffff88800c0f0580)
flags: 0x100000000000200(slab|node=0|zone=1)
page:00000000fe45cd86 refcount:1 mapcount:0
mapping:0000000000000000 index:0x0 pfn:0xc0f0
raw: 0000000000000000 0000000080100010 00000001ffffffff
0000000000000000
raw: 0100000000000200 ffffea00003a2c80 dead000000000004
ffff8880078418c0
page dumped because: kasan: bad access detected
ffff88800c0f0400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc
Memory state around the buggy address:
>ffff88800c0f0500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88800c0f0480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88800c0f0580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
powerpc/secvar: fix refcount leak in format_show()
Refcount leak will happen when format_show returns failure in multiple
cases. Unified management of of_node_put can fix this problem.