In the Linux kernel, the following vulnerability has been resolved:
powerpc/imc-pmu: Fix use of mutex in IRQs disabled section
Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP
and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event.
Command to trigger the warning:
# perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5
Performance counter stats for 'sleep 5':
0 thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/
5.002117947 seconds time elapsed
0.000131000 seconds user
0.001063000 seconds sys
Below is snippet of the warning in dmesg:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec
preempt_count: 2, expected: 0
4 locks held by perf-exec/2869:
#0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90
#1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0
#2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510
#3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510
irq event stamp: 4806
hardirqs last enabled at (4805): [<c000000000f65b94>] _raw_spin_unlock_irqrestore+0x94/0xd0
hardirqs last disabled at (4806): [<c0000000003fae44>] perf_event_exec+0x394/0x510
softirqs last enabled at (0): [<c00000000013c404>] copy_process+0xc34/0x1ff0
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
Call Trace:
dump_stack_lvl+0x98/0xe0 (unreliable)
__might_resched+0x2f8/0x310
__mutex_lock+0x6c/0x13f0
thread_imc_event_add+0xf4/0x1b0
event_sched_in+0xe0/0x210
merge_sched_in+0x1f0/0x600
visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0
ctx_flexible_sched_in+0xcc/0x140
ctx_sched_in+0x20c/0x2a0
ctx_resched+0x104/0x1c0
perf_event_exec+0x340/0x510
begin_new_exec+0x730/0xef0
load_elf_binary+0x3f8/0x1e10
...
do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0
WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0
CPU: 36 PID: 2869 Comm: sleep Tainted: G W 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
NIP: c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670
REGS: c00000004d2134e0 TRAP: 0700 Tainted: G W (6.2.0-rc2-00011-g1247637727f2)
MSR: 9000000000021033 <SF,HV,ME,IR,DR,RI,LE> CR: 48002824 XER: 00000000
CFAR: c00000000013fb64 IRQMASK: 1
The above warning triggered because the current imc-pmu code uses mutex
lock in interrupt disabled sections. The function mutex_lock()
internally calls __might_resched(), which will check if IRQs are
disabled and in case IRQs are disabled, it will trigger the warning.
Fix the issue by changing the mutex lock to spinlock.
[mpe: Fix comments, trim oops in change log, add reported-by tags]
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: Fix overflow before widen in the bitmap_ip_create() function.
When first_ip is 0, last_ip is 0xFFFFFFFF, and netmask is 31, the value of
an arithmetic expression 2 << (netmask - mask_bits - 1) is subject
to overflow due to a failure casting operands to a larger data type
before performing the arithmetic.
Note that it's harmless since the value will be checked at the next step.
Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
net: mdio: validate parameter addr in mdiobus_get_phy()
The caller may pass any value as addr, what may result in an out-of-bounds
access to array mdio_map. One existing case is stmmac_init_phy() that
may pass -1 as addr. Therefore validate addr before using it.
In the Linux kernel, the following vulnerability has been resolved:
l2tp: close all race conditions in l2tp_tunnel_register()
The code in l2tp_tunnel_register() is racy in several ways:
1. It modifies the tunnel socket _after_ publishing it.
2. It calls setup_udp_tunnel_sock() on an existing socket without
locking.
3. It changes sock lock class on fly, which triggers many syzbot
reports.
This patch amends all of them by moving socket initialization code
before publishing and under sock lock. As suggested by Jakub, the
l2tp lockdep class is not necessary as we can just switch to
bh_lock_sock_nested().
In the Linux kernel, the following vulnerability has been resolved:
net: nfc: Fix use-after-free in local_cleanup()
Fix a use-after-free that occurs in kfree_skb() called from
local_cleanup(). This could happen when killing nfc daemon (e.g. neard)
after detaching an nfc device.
When detaching an nfc device, local_cleanup() called from
nfc_llcp_unregister_device() frees local->rx_pending and decreases
local->ref by kref_put() in nfc_llcp_local_put().
In the terminating process, nfc daemon releases all sockets and it leads
to decreasing local->ref. After the last release of local->ref,
local_cleanup() called from local_release() frees local->rx_pending
again, which leads to the bug.
Setting local->rx_pending to NULL in local_cleanup() could prevent
use-after-free when local_cleanup() is called twice.
Found by a modified version of syzkaller.
BUG: KASAN: use-after-free in kfree_skb()
Call Trace:
dump_stack_lvl (lib/dump_stack.c:106)
print_address_description.constprop.0.cold (mm/kasan/report.c:306)
kasan_check_range (mm/kasan/generic.c:189)
kfree_skb (net/core/skbuff.c:955)
local_cleanup (net/nfc/llcp_core.c:159)
nfc_llcp_local_put.part.0 (net/nfc/llcp_core.c:172)
nfc_llcp_local_put (net/nfc/llcp_core.c:181)
llcp_sock_destruct (net/nfc/llcp_sock.c:959)
__sk_destruct (net/core/sock.c:2133)
sk_destruct (net/core/sock.c:2181)
__sk_free (net/core/sock.c:2192)
sk_free (net/core/sock.c:2203)
llcp_sock_release (net/nfc/llcp_sock.c:646)
__sock_release (net/socket.c:650)
sock_close (net/socket.c:1365)
__fput (fs/file_table.c:306)
task_work_run (kernel/task_work.c:179)
ptrace_notify (kernel/signal.c:2354)
syscall_exit_to_user_mode_prepare (kernel/entry/common.c:278)
syscall_exit_to_user_mode (kernel/entry/common.c:296)
do_syscall_64 (arch/x86/entry/common.c:86)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:106)
Allocated by task 4719:
kasan_save_stack (mm/kasan/common.c:45)
__kasan_slab_alloc (mm/kasan/common.c:325)
slab_post_alloc_hook (mm/slab.h:766)
kmem_cache_alloc_node (mm/slub.c:3497)
__alloc_skb (net/core/skbuff.c:552)
pn533_recv_response (drivers/nfc/pn533/usb.c:65)
__usb_hcd_giveback_urb (drivers/usb/core/hcd.c:1671)
usb_giveback_urb_bh (drivers/usb/core/hcd.c:1704)
tasklet_action_common.isra.0 (kernel/softirq.c:797)
__do_softirq (kernel/softirq.c:571)
Freed by task 1901:
kasan_save_stack (mm/kasan/common.c:45)
kasan_set_track (mm/kasan/common.c:52)
kasan_save_free_info (mm/kasan/genericdd.c:518)
__kasan_slab_free (mm/kasan/common.c:236)
kmem_cache_free (mm/slub.c:3809)
kfree_skbmem (net/core/skbuff.c:874)
kfree_skb (net/core/skbuff.c:931)
local_cleanup (net/nfc/llcp_core.c:159)
nfc_llcp_unregister_device (net/nfc/llcp_core.c:1617)
nfc_unregister_device (net/nfc/core.c:1179)
pn53x_unregister_nfc (drivers/nfc/pn533/pn533.c:2846)
pn533_usb_disconnect (drivers/nfc/pn533/usb.c:579)
usb_unbind_interface (drivers/usb/core/driver.c:458)
device_release_driver_internal (drivers/base/dd.c:1279)
bus_remove_device (drivers/base/bus.c:529)
device_del (drivers/base/core.c:3665)
usb_disable_device (drivers/usb/core/message.c:1420)
usb_disconnect (drivers/usb/core.c:2261)
hub_event (drivers/usb/core/hub.c:5833)
process_one_work (arch/x86/include/asm/jump_label.h:27 include/linux/jump_label.h:212 include/trace/events/workqueue.h:108 kernel/workqueue.c:2281)
worker_thread (include/linux/list.h:282 kernel/workqueue.c:2423)
kthread (kernel/kthread.c:319)
ret_from_fork (arch/x86/entry/entry_64.S:301)
In the Linux kernel, the following vulnerability has been resolved:
bnxt: Do not read past the end of test names
Test names were being concatenated based on a offset beyond the end of
the first name, which tripped the buffer overflow detection logic:
detected buffer overflow in strnlen
[...]
Call Trace:
bnxt_ethtool_init.cold+0x18/0x18
Refactor struct hwrm_selftest_qlist_output to use an actual array,
and adjust the concatenation to use snprintf() rather than a series of
strncat() calls.
In the Linux kernel, the following vulnerability has been resolved:
HID: betop: check shape of output reports
betopff_init() only checks the total sum of the report counts for each
report field to be at least 4, but hid_betopff_play() expects 4 report
fields.
A device advertising an output report with one field and 4 report counts
would pass the check but crash the kernel with a NULL pointer dereference
in hid_betopff_play().
In the Linux kernel, the following vulnerability has been resolved:
tracing: Make sure trace_printk() can output as soon as it can be used
Currently trace_printk() can be used as soon as early_trace_init() is
called from start_kernel(). But if a crash happens, and
"ftrace_dump_on_oops" is set on the kernel command line, all you get will
be:
[ 0.456075] <idle>-0 0dN.2. 347519us : Unknown type 6
[ 0.456075] <idle>-0 0dN.2. 353141us : Unknown type 6
[ 0.456075] <idle>-0 0dN.2. 358684us : Unknown type 6
This is because the trace_printk() event (type 6) hasn't been registered
yet. That gets done via an early_initcall(), which may be early, but not
early enough.
Instead of registering the trace_printk() event (and other ftrace events,
which are not trace events) via an early_initcall(), have them registered at
the same time that trace_printk() can be used. This way, if there is a
crash before early_initcall(), then the trace_printk()s will actually be
useful.
In the Linux kernel, the following vulnerability has been resolved:
cifs: fix potential memory leaks in session setup
Make sure to free cifs_ses::auth_key.response before allocating it as
we might end up leaking memory in reconnect or mounting.
In the Linux kernel, the following vulnerability has been resolved:
ipv4: prevent potential spectre v1 gadget in fib_metrics_match()
if (!type)
continue;
if (type > RTAX_MAX)
return false;
...
fi_val = fi->fib_metrics->metrics[type - 1];
@type being used as an array index, we need to prevent
cpu speculation or risk leaking kernel memory content.