In the Linux kernel, the following vulnerability has been resolved:
btrfs: reject invalid reloc tree root keys with stack dump
[BUG]
Syzbot reported a crash that an ASSERT() got triggered inside
prepare_to_merge().
That ASSERT() makes sure the reloc tree is properly pointed back by its
subvolume tree.
[CAUSE]
After more debugging output, it turns out we had an invalid reloc tree:
BTRFS error (device loop1): reloc tree mismatch, root 8 has no reloc root, expect reloc root key (-8, 132, 8) gen 17
Note the above root key is (TREE_RELOC_OBJECTID, ROOT_ITEM,
QUOTA_TREE_OBJECTID), meaning it's a reloc tree for quota tree.
But reloc trees can only exist for subvolumes, as for non-subvolume
trees, we just COW the involved tree block, no need to create a reloc
tree since those tree blocks won't be shared with other trees.
Only subvolumes tree can share tree blocks with other trees (thus they
have BTRFS_ROOT_SHAREABLE flag).
Thus this new debug output proves my previous assumption that corrupted
on-disk data can trigger that ASSERT().
[FIX]
Besides the dedicated fix and the graceful exit, also let tree-checker to
check such root keys, to make sure reloc trees can only exist for subvolumes.
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:
blk-mq: avoid double ->queue_rq() because of early timeout
David Jeffery found one double ->queue_rq() issue, so far it can
be triggered in VM use case because of long vmexit latency or preempt
latency of vCPU pthread or long page fault in vCPU pthread, then block
IO req could be timed out before queuing the request to hardware but after
calling blk_mq_start_request() during ->queue_rq(), then timeout handler
may handle it by requeue, then double ->queue_rq() is caused, and kernel
panic.
So far, it is driver's responsibility to cover the race between timeout
and completion, so it seems supposed to be solved in driver in theory,
given driver has enough knowledge.
But it is really one common problem, lots of driver could have similar
issue, and could be hard to fix all affected drivers, even it isn't easy
for driver to handle the race. So David suggests this patch by draining
in-progress ->queue_rq() for solving this issue.
In the Linux kernel, the following vulnerability has been resolved:
tipc: fix a null-ptr-deref in tipc_topsrv_accept
syzbot found a crash in tipc_topsrv_accept:
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
Workqueue: tipc_rcv tipc_topsrv_accept
RIP: 0010:kernel_accept+0x22d/0x350 net/socket.c:3487
Call Trace:
<TASK>
tipc_topsrv_accept+0x197/0x280 net/tipc/topsrv.c:460
process_one_work+0x991/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
It was caused by srv->listener that might be set to null by
tipc_topsrv_stop() in net .exit whereas it's still used in
tipc_topsrv_accept() worker.
srv->listener is protected by srv->idr_lock in tipc_topsrv_stop(), so add
a check for srv->listener under srv->idr_lock in tipc_topsrv_accept() to
avoid the null-ptr-deref. To ensure the lsock is not released during the
tipc_topsrv_accept(), move sock_release() after tipc_topsrv_work_stop()
where it's waiting until the tipc_topsrv_accept worker to be done.
Note that sk_callback_lock is used to protect sk->sk_user_data instead of
srv->listener, and it should check srv in tipc_topsrv_listener_data_ready()
instead. This also ensures that no more tipc_topsrv_accept worker will be
started after tipc_conn_close() is called in tipc_topsrv_stop() where it
sets sk->sk_user_data to null.
In the Linux kernel, the following vulnerability has been resolved:
tracing/hist: Fix out-of-bound write on 'action_data.var_ref_idx'
When generate a synthetic event with many params and then create a trace
action for it [1], kernel panic happened [2].
It is because that in trace_action_create() 'data->n_params' is up to
SYNTH_FIELDS_MAX (current value is 64), and array 'data->var_ref_idx'
keeps indices into array 'hist_data->var_refs' for each synthetic event
param, but the length of 'data->var_ref_idx' is TRACING_MAP_VARS_MAX
(current value is 16), so out-of-bound write happened when 'data->n_params'
more than 16. In this case, 'data->match_data.event' is overwritten and
eventually cause the panic.
To solve the issue, adjust the length of 'data->var_ref_idx' to be
SYNTH_FIELDS_MAX and add sanity checks to avoid out-of-bound write.
[1]
# cd /sys/kernel/tracing/
# echo "my_synth_event int v1; int v2; int v3; int v4; int v5; int v6;\
int v7; int v8; int v9; int v10; int v11; int v12; int v13; int v14;\
int v15; int v16; int v17; int v18; int v19; int v20; int v21; int v22;\
int v23; int v24; int v25; int v26; int v27; int v28; int v29; int v30;\
int v31; int v32; int v33; int v34; int v35; int v36; int v37; int v38;\
int v39; int v40; int v41; int v42; int v43; int v44; int v45; int v46;\
int v47; int v48; int v49; int v50; int v51; int v52; int v53; int v54;\
int v55; int v56; int v57; int v58; int v59; int v60; int v61; int v62;\
int v63" >> synthetic_events
# echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="bash"' >> \
events/sched/sched_waking/trigger
# echo "hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(\
pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,\
pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,\
pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,pid,\
pid,pid,pid,pid,pid,pid,pid,pid,pid)" >> events/sched/sched_switch/trigger
[2]
BUG: unable to handle page fault for address: ffff91c900000000
PGD 61001067 P4D 61001067 PUD 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 2 PID: 322 Comm: bash Tainted: G W 6.1.0-rc8+ #229
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:strcmp+0xc/0x30
Code: 75 f7 31 d2 44 0f b6 04 16 44 88 04 11 48 83 c2 01 45 84 c0 75 ee
c3 cc cc cc cc 0f 1f 00 31 c0 eb 08 48 83 c0 01 84 d2 74 13 <0f> b6 14
07 3a 14 06 74 ef 19 c0 83 c8 01 c3 cc cc cc cc 31 c3
RSP: 0018:ffff9b3b00f53c48 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffffba958a68 RCX: 0000000000000000
RDX: 0000000000000010 RSI: ffff91c943d33a90 RDI: ffff91c900000000
RBP: ffff91c900000000 R08: 00000018d604b529 R09: 0000000000000000
R10: ffff91c9483eddb1 R11: ffff91ca483eddab R12: ffff91c946171580
R13: ffff91c9479f0538 R14: ffff91c9457c2848 R15: ffff91c9479f0538
FS: 00007f1d1cfbe740(0000) GS:ffff91c9bdc80000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff91c900000000 CR3: 0000000006316000 CR4: 00000000000006e0
Call Trace:
<TASK>
__find_event_file+0x55/0x90
action_create+0x76c/0x1060
event_hist_trigger_parse+0x146d/0x2060
? event_trigger_write+0x31/0xd0
trigger_process_regex+0xbb/0x110
event_trigger_write+0x6b/0xd0
vfs_write+0xc8/0x3e0
? alloc_fd+0xc0/0x160
? preempt_count_add+0x4d/0xa0
? preempt_count_add+0x70/0xa0
ksys_write+0x5f/0xe0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f1d1d0cf077
Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e
fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00
f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74
RSP: 002b:00007ffcebb0e568 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000143 RCX: 00007f1d1d0cf077
RDX: 0000000000000143 RSI: 00005639265aa7e0 RDI: 0000000000000001
RBP: 00005639265aa7e0 R08: 000000000000000a R09: 0000000000000142
R
---truncated---
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---