In the Linux kernel, the following vulnerability has been resolved:
mm/swap: fix swap_info_struct race between swapoff and get_swap_pages()
The si->lock must be held when deleting the si from the available list.
Otherwise, another thread can re-add the si to the available list, which
can lead to memory corruption. The only place we have found where this
happens is in the swapoff path. This case can be described as below:
core 0 core 1
swapoff
del_from_avail_list(si) waiting
try lock si->lock acquire swap_avail_lock
and re-add si into
swap_avail_head
acquire si->lock but missing si already being added again, and continuing
to clear SWP_WRITEOK, etc.
It can be easily found that a massive warning messages can be triggered
inside get_swap_pages() by some special cases, for example, we call
madvise(MADV_PAGEOUT) on blocks of touched memory concurrently, meanwhile,
run much swapon-swapoff operations (e.g. stress-ng-swap).
However, in the worst case, panic can be caused by the above scene. In
swapoff(), the memory used by si could be kept in swap_info[] after
turning off a swap. This means memory corruption will not be caused
immediately until allocated and reset for a new swap in the swapon path.
A panic message caused: (with CONFIG_PLIST_DEBUG enabled)
------------[ cut here ]------------
top: 00000000e58a3003, n: 0000000013e75cda, p: 000000008cd4451a
prev: 0000000035b1e58a, n: 000000008cd4451a, p: 000000002150ee8d
next: 000000008cd4451a, n: 000000008cd4451a, p: 000000008cd4451a
WARNING: CPU: 21 PID: 1843 at lib/plist.c:60 plist_check_prev_next_node+0x50/0x70
Modules linked in: rfkill(E) crct10dif_ce(E)...
CPU: 21 PID: 1843 Comm: stress-ng Kdump: ... 5.10.134+
Hardware name: Alibaba Cloud ECS, BIOS 0.0.0 02/06/2015
pstate: 60400005 (nZCv daif +PAN -UAO -TCO BTYPE=--)
pc : plist_check_prev_next_node+0x50/0x70
lr : plist_check_prev_next_node+0x50/0x70
sp : ffff0018009d3c30
x29: ffff0018009d3c40 x28: ffff800011b32a98
x27: 0000000000000000 x26: ffff001803908000
x25: ffff8000128ea088 x24: ffff800011b32a48
x23: 0000000000000028 x22: ffff001800875c00
x21: ffff800010f9e520 x20: ffff001800875c00
x19: ffff001800fdc6e0 x18: 0000000000000030
x17: 0000000000000000 x16: 0000000000000000
x15: 0736076307640766 x14: 0730073007380731
x13: 0736076307640766 x12: 0730073007380731
x11: 000000000004058d x10: 0000000085a85b76
x9 : ffff8000101436e4 x8 : ffff800011c8ce08
x7 : 0000000000000000 x6 : 0000000000000001
x5 : ffff0017df9ed338 x4 : 0000000000000001
x3 : ffff8017ce62a000 x2 : ffff0017df9ed340
x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
plist_check_prev_next_node+0x50/0x70
plist_check_head+0x80/0xf0
plist_add+0x28/0x140
add_to_avail_list+0x9c/0xf0
_enable_swap_info+0x78/0xb4
__do_sys_swapon+0x918/0xa10
__arm64_sys_swapon+0x20/0x30
el0_svc_common+0x8c/0x220
do_el0_svc+0x2c/0x90
el0_svc+0x1c/0x30
el0_sync_handler+0xa8/0xb0
el0_sync+0x148/0x180
irq event stamp: 2082270
Now, si->lock locked before calling 'del_from_avail_list()' to make sure
other thread see the si had been deleted and SWP_WRITEOK cleared together,
will not reinsert again.
This problem exists in versions after stable 5.10.y.
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_fq: fix integer overflow of "credit"
if sch_fq is configured with "initial quantum" having values greater than
INT_MAX, the first assignment of "credit" does signed integer overflow to
a very negative value.
In this situation, the syzkaller script provided by Cristoph triggers the
CPU soft-lockup warning even with few sockets. It's not an infinite loop,
but "credit" wasn't probably meant to be minus 2Gb for each new flow.
Capping "initial quantum" to INT_MAX proved to fix the issue.
v2: validation of "initial quantum" is done in fq_policy, instead of open
coding in fq_change() _ suggested by Jakub Kicinski
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: Avoid nf_ct_helper_hash uses after free
If nf_conntrack_init_start() fails (for example due to a
register_nf_conntrack_bpf() failure), the nf_conntrack_helper_fini()
clean-up path frees the nf_ct_helper_hash map.
When built with NF_CONNTRACK=y, further netfilter modules (e.g:
netfilter_conntrack_ftp) can still be loaded and call
nf_conntrack_helpers_register(), independently of whether nf_conntrack
initialized correctly. This accesses the nf_ct_helper_hash dangling
pointer and causes a uaf, possibly leading to random memory corruption.
This patch guards nf_conntrack_helper_register() from accessing a freed
or uninitialized nf_ct_helper_hash pointer and fixes possible
uses-after-free when loading a conntrack module.
In the Linux kernel, the following vulnerability has been resolved:
md: fix soft lockup in status_resync
status_resync() will calculate 'curr_resync - recovery_active' to show
user a progress bar like following:
[============>........] resync = 61.4%
'curr_resync' and 'recovery_active' is updated in md_do_sync(), and
status_resync() can read them concurrently, hence it's possible that
'curr_resync - recovery_active' can overflow to a huge number. In this
case status_resync() will be stuck in the loop to print a large amount
of '=', which will end up soft lockup.
Fix the problem by setting 'resync' to MD_RESYNC_ACTIVE in this case,
this way resync in progress will be reported to user.
In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix possible data races in gfs2_show_options()
Some fields such as gt_logd_secs of the struct gfs2_tune are accessed
without holding the lock gt_spin in gfs2_show_options():
val = sdp->sd_tune.gt_logd_secs;
if (val != 30)
seq_printf(s, ",commit=%d", val);
And thus can cause data races when gfs2_show_options() and other functions
such as gfs2_reconfigure() are concurrently executed:
spin_lock(>->gt_spin);
gt->gt_logd_secs = newargs->ar_commit;
To fix these possible data races, the lock sdp->sd_tune.gt_spin is
acquired before accessing the fields of gfs2_tune and released after these
accesses.
Further changes by Andreas:
- Don't hold the spin lock over the seq_printf operations.
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: Fix potential shift-out-of-bounds in brcmf_fw_alloc_request()
This patch fixes a shift-out-of-bounds in brcmfmac that occurs in
BIT(chiprev) when a 'chiprev' provided by the device is too large.
It should also not be equal to or greater than BITS_PER_TYPE(u32)
as we do bitwise AND with a u32 variable and BIT(chiprev). The patch
adds a check that makes the function return NULL if that is the case.
Note that the NULL case is later handled by the bus-specific caller,
brcmf_usb_probe_cb() or brcmf_usb_reset_resume(), for example.
Found by a modified version of syzkaller.
UBSAN: shift-out-of-bounds in drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
shift exponent 151055786 is too large for 64-bit type 'long unsigned int'
CPU: 0 PID: 1885 Comm: kworker/0:2 Tainted: G O 5.14.0+ #132
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Workqueue: usb_hub_wq hub_event
Call Trace:
dump_stack_lvl+0x57/0x7d
ubsan_epilogue+0x5/0x40
__ubsan_handle_shift_out_of_bounds.cold+0x53/0xdb
? lock_chain_count+0x20/0x20
brcmf_fw_alloc_request.cold+0x19/0x3ea
? brcmf_fw_get_firmwares+0x250/0x250
? brcmf_usb_ioctl_resp_wait+0x1a7/0x1f0
brcmf_usb_get_fwname+0x114/0x1a0
? brcmf_usb_reset_resume+0x120/0x120
? number+0x6c4/0x9a0
brcmf_c_process_clm_blob+0x168/0x590
? put_dec+0x90/0x90
? enable_ptr_key_workfn+0x20/0x20
? brcmf_common_pd_remove+0x50/0x50
? rcu_read_lock_sched_held+0xa1/0xd0
brcmf_c_preinit_dcmds+0x673/0xc40
? brcmf_c_set_joinpref_default+0x100/0x100
? rcu_read_lock_sched_held+0xa1/0xd0
? rcu_read_lock_bh_held+0xb0/0xb0
? lock_acquire+0x19d/0x4e0
? find_held_lock+0x2d/0x110
? brcmf_usb_deq+0x1cc/0x260
? mark_held_locks+0x9f/0xe0
? lockdep_hardirqs_on_prepare+0x273/0x3e0
? _raw_spin_unlock_irqrestore+0x47/0x50
? trace_hardirqs_on+0x1c/0x120
? brcmf_usb_deq+0x1a7/0x260
? brcmf_usb_rx_fill_all+0x5a/0xf0
brcmf_attach+0x246/0xd40
? wiphy_new_nm+0x1476/0x1d50
? kmemdup+0x30/0x40
brcmf_usb_probe+0x12de/0x1690
? brcmf_usbdev_qinit.constprop.0+0x470/0x470
usb_probe_interface+0x25f/0x710
really_probe+0x1be/0xa90
__driver_probe_device+0x2ab/0x460
? usb_match_id.part.0+0x88/0xc0
driver_probe_device+0x49/0x120
__device_attach_driver+0x18a/0x250
? driver_allows_async_probing+0x120/0x120
bus_for_each_drv+0x123/0x1a0
? bus_rescan_devices+0x20/0x20
? lockdep_hardirqs_on_prepare+0x273/0x3e0
? trace_hardirqs_on+0x1c/0x120
__device_attach+0x207/0x330
? device_bind_driver+0xb0/0xb0
? kobject_uevent_env+0x230/0x12c0
bus_probe_device+0x1a2/0x260
device_add+0xa61/0x1ce0
? __mutex_unlock_slowpath+0xe7/0x660
? __fw_devlink_link_to_suppliers+0x550/0x550
usb_set_configuration+0x984/0x1770
? kernfs_create_link+0x175/0x230
usb_generic_driver_probe+0x69/0x90
usb_probe_device+0x9c/0x220
really_probe+0x1be/0xa90
__driver_probe_device+0x2ab/0x460
driver_probe_device+0x49/0x120
__device_attach_driver+0x18a/0x250
? driver_allows_async_probing+0x120/0x120
bus_for_each_drv+0x123/0x1a0
? bus_rescan_devices+0x20/0x20
? lockdep_hardirqs_on_prepare+0x273/0x3e0
? trace_hardirqs_on+0x1c/0x120
__device_attach+0x207/0x330
? device_bind_driver+0xb0/0xb0
? kobject_uevent_env+0x230/0x12c0
bus_probe_device+0x1a2/0x260
device_add+0xa61/0x1ce0
? __fw_devlink_link_to_suppliers+0x550/0x550
usb_new_device.cold+0x463/0xf66
? hub_disconnect+0x400/0x400
? _raw_spin_unlock_irq+0x24/0x30
hub_event+0x10d5/0x3330
? hub_port_debounce+0x280/0x280
? __lock_acquire+0x1671/0x5790
? wq_calc_node_cpumask+0x170/0x2a0
? lock_release+0x640/0x640
? rcu_read_lock_sched_held+0xa1/0xd0
? rcu_read_lock_bh_held+0xb0/0xb0
? lockdep_hardirqs_on_prepare+0x273/0x3e0
process_one_work+0x873/0x13e0
? lock_release+0x640/0x640
? pwq_dec_nr_in_flight+0x320/0x320
? rwlock_bug.part.0+0x90/0x90
worker_thread+0x8b/0xd10
? __kthread_parkme+0xd9/0x1d0
? pr
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
media: solo6x10: fix possible memory leak in solo_sysfs_init()
If device_register() returns error in solo_sysfs_init(), the
name allocated by dev_set_name() need be freed. As comment of
device_register() says, it should use put_device() to give up
the reference in the error path. So fix this by calling
put_device(), then the name can be freed in kobject_cleanup().
In the Linux kernel, the following vulnerability has been resolved:
vme: Fix error not catched in fake_init()
In fake_init(), __root_device_register() is possible to fail but it's
ignored, which can cause unregistering vme_root fail when exit.
general protection fault,
probably for non-canonical address 0xdffffc000000008c
KASAN: null-ptr-deref in range [0x0000000000000460-0x0000000000000467]
RIP: 0010:root_device_unregister+0x26/0x60
Call Trace:
<TASK>
__x64_sys_delete_module+0x34f/0x540
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Return error when __root_device_register() fails.