| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
memcg: protect concurrent access to mem_cgroup_idr
Commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after
many small jobs") decoupled the memcg IDs from the CSS ID space to fix the
cgroup creation failures. It introduced IDR to maintain the memcg ID
space. The IDR depends on external synchronization mechanisms for
modifications. For the mem_cgroup_idr, the idr_alloc() and idr_replace()
happen within css callback and thus are protected through cgroup_mutex
from concurrent modifications. However idr_remove() for mem_cgroup_idr
was not protected against concurrency and can be run concurrently for
different memcgs when they hit their refcnt to zero. Fix that.
We have been seeing list_lru based kernel crashes at a low frequency in
our fleet for a long time. These crashes were in different part of
list_lru code including list_lru_add(), list_lru_del() and reparenting
code. Upon further inspection, it looked like for a given object (dentry
and inode), the super_block's list_lru didn't have list_lru_one for the
memcg of that object. The initial suspicions were either the object is
not allocated through kmem_cache_alloc_lru() or somehow
memcg_list_lru_alloc() failed to allocate list_lru_one() for a memcg but
returned success. No evidence were found for these cases.
Looking more deeply, we started seeing situations where valid memcg's id
is not present in mem_cgroup_idr and in some cases multiple valid memcgs
have same id and mem_cgroup_idr is pointing to one of them. So, the most
reasonable explanation is that these situations can happen due to race
between multiple idr_remove() calls or race between
idr_alloc()/idr_replace() and idr_remove(). These races are causing
multiple memcgs to acquire the same ID and then offlining of one of them
would cleanup list_lrus on the system for all of them. Later access from
other memcgs to the list_lru cause crashes due to missing list_lru_one. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Always drain health in shutdown callback
There is no point in recovery during device shutdown. if health
work started need to wait for it to avoid races and NULL pointer
access.
Hence, drain health WQ on shutdown callback. |
| In the Linux kernel, the following vulnerability has been resolved:
cachefiles: cyclic allocation of msg_id to avoid reuse
Reusing the msg_id after a maliciously completed reopen request may cause
a read request to remain unprocessed and result in a hung, as shown below:
t1 | t2 | t3
-------------------------------------------------
cachefiles_ondemand_select_req
cachefiles_ondemand_object_is_close(A)
cachefiles_ondemand_set_object_reopening(A)
queue_work(fscache_object_wq, &info->work)
ondemand_object_worker
cachefiles_ondemand_init_object(A)
cachefiles_ondemand_send_req(OPEN)
// get msg_id 6
wait_for_completion(&req_A->done)
cachefiles_ondemand_daemon_read
// read msg_id 6 req_A
cachefiles_ondemand_get_fd
copy_to_user
// Malicious completion msg_id 6
copen 6,-1
cachefiles_ondemand_copen
complete(&req_A->done)
// will not set the object to close
// because ondemand_id && fd is valid.
// ondemand_object_worker() is done
// but the object is still reopening.
// new open req_B
cachefiles_ondemand_init_object(B)
cachefiles_ondemand_send_req(OPEN)
// reuse msg_id 6
process_open_req
copen 6,A.size
// The expected failed copen was executed successfully
Expect copen to fail, and when it does, it closes fd, which sets the
object to close, and then close triggers reopen again. However, due to
msg_id reuse resulting in a successful copen, the anonymous fd is not
closed until the daemon exits. Therefore read requests waiting for reopen
to complete may trigger hung task.
To avoid this issue, allocate the msg_id cyclically to avoid reusing the
msg_id for a very short duration of time. |
| In the Linux kernel, the following vulnerability has been resolved:
filelock: Fix fcntl/close race recovery compat path
When I wrote commit 3cad1bc01041 ("filelock: Remove locks reliably when
fcntl/close race is detected"), I missed that there are two copies of the
code I was patching: The normal version, and the version for 64-bit offsets
on 32-bit kernels.
Thanks to Greg KH for stumbling over this while doing the stable
backport...
Apply exactly the same fix to the compat path for 32-bit kernels. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/lima: mask irqs in timeout path before hard reset
There is a race condition in which a rendering job might take just long
enough to trigger the drm sched job timeout handler but also still
complete before the hard reset is done by the timeout handler.
This runs into race conditions not expected by the timeout handler.
In some very specific cases it currently may result in a refcount
imbalance on lima_pm_idle, with a stack dump such as:
[10136.669170] WARNING: CPU: 0 PID: 0 at drivers/gpu/drm/lima/lima_devfreq.c:205 lima_devfreq_record_idle+0xa0/0xb0
...
[10136.669459] pc : lima_devfreq_record_idle+0xa0/0xb0
...
[10136.669628] Call trace:
[10136.669634] lima_devfreq_record_idle+0xa0/0xb0
[10136.669646] lima_sched_pipe_task_done+0x5c/0xb0
[10136.669656] lima_gp_irq_handler+0xa8/0x120
[10136.669666] __handle_irq_event_percpu+0x48/0x160
[10136.669679] handle_irq_event+0x4c/0xc0
We can prevent that race condition entirely by masking the irqs at the
beginning of the timeout handler, at which point we give up on waiting
for that job entirely.
The irqs will be enabled again at the next hard reset which is already
done as a recovery by the timeout handler. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Fix a data race on last_boosted_vcpu in kvm_vcpu_on_spin()
Use {READ,WRITE}_ONCE() to access kvm->last_boosted_vcpu to ensure the
loads and stores are atomic. In the extremely unlikely scenario the
compiler tears the stores, it's theoretically possible for KVM to attempt
to get a vCPU using an out-of-bounds index, e.g. if the write is split
into multiple 8-bit stores, and is paired with a 32-bit load on a VM with
257 vCPUs:
CPU0 CPU1
last_boosted_vcpu = 0xff;
(last_boosted_vcpu = 0x100)
last_boosted_vcpu[15:8] = 0x01;
i = (last_boosted_vcpu = 0x1ff)
last_boosted_vcpu[7:0] = 0x00;
vcpu = kvm->vcpu_array[0x1ff];
As detected by KCSAN:
BUG: KCSAN: data-race in kvm_vcpu_on_spin [kvm] / kvm_vcpu_on_spin [kvm]
write to 0xffffc90025a92344 of 4 bytes by task 4340 on cpu 16:
kvm_vcpu_on_spin (arch/x86/kvm/../../../virt/kvm/kvm_main.c:4112) kvm
handle_pause (arch/x86/kvm/vmx/vmx.c:5929) kvm_intel
vmx_handle_exit (arch/x86/kvm/vmx/vmx.c:?
arch/x86/kvm/vmx/vmx.c:6606) kvm_intel
vcpu_run (arch/x86/kvm/x86.c:11107 arch/x86/kvm/x86.c:11211) kvm
kvm_arch_vcpu_ioctl_run (arch/x86/kvm/x86.c:?) kvm
kvm_vcpu_ioctl (arch/x86/kvm/../../../virt/kvm/kvm_main.c:?) kvm
__se_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:904 fs/ioctl.c:890)
__x64_sys_ioctl (fs/ioctl.c:890)
x64_sys_call (arch/x86/entry/syscall_64.c:33)
do_syscall_64 (arch/x86/entry/common.c:?)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
read to 0xffffc90025a92344 of 4 bytes by task 4342 on cpu 4:
kvm_vcpu_on_spin (arch/x86/kvm/../../../virt/kvm/kvm_main.c:4069) kvm
handle_pause (arch/x86/kvm/vmx/vmx.c:5929) kvm_intel
vmx_handle_exit (arch/x86/kvm/vmx/vmx.c:?
arch/x86/kvm/vmx/vmx.c:6606) kvm_intel
vcpu_run (arch/x86/kvm/x86.c:11107 arch/x86/kvm/x86.c:11211) kvm
kvm_arch_vcpu_ioctl_run (arch/x86/kvm/x86.c:?) kvm
kvm_vcpu_ioctl (arch/x86/kvm/../../../virt/kvm/kvm_main.c:?) kvm
__se_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:904 fs/ioctl.c:890)
__x64_sys_ioctl (fs/ioctl.c:890)
x64_sys_call (arch/x86/entry/syscall_64.c:33)
do_syscall_64 (arch/x86/entry/common.c:?)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
value changed: 0x00000012 -> 0x00000000 |
| In the Linux kernel, the following vulnerability has been resolved:
ima: Avoid blocking in RCU read-side critical section
A panic happens in ima_match_policy:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
PGD 42f873067 P4D 0
Oops: 0000 [#1] SMP NOPTI
CPU: 5 PID: 1286325 Comm: kubeletmonit.sh
Kdump: loaded Tainted: P
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 0.0.0 02/06/2015
RIP: 0010:ima_match_policy+0x84/0x450
Code: 49 89 fc 41 89 cf 31 ed 89 44 24 14 eb 1c 44 39
7b 18 74 26 41 83 ff 05 74 20 48 8b 1b 48 3b 1d
f2 b9 f4 00 0f 84 9c 01 00 00 <44> 85 73 10 74 ea
44 8b 6b 14 41 f6 c5 01 75 d4 41 f6 c5 02 74 0f
RSP: 0018:ff71570009e07a80 EFLAGS: 00010207
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000200
RDX: ffffffffad8dc7c0 RSI: 0000000024924925 RDI: ff3e27850dea2000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffffabfce739
R10: ff3e27810cc42400 R11: 0000000000000000 R12: ff3e2781825ef970
R13: 00000000ff3e2785 R14: 000000000000000c R15: 0000000000000001
FS: 00007f5195b51740(0000)
GS:ff3e278b12d40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000626d24002 CR4: 0000000000361ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
ima_get_action+0x22/0x30
process_measurement+0xb0/0x830
? page_add_file_rmap+0x15/0x170
? alloc_set_pte+0x269/0x4c0
? prep_new_page+0x81/0x140
? simple_xattr_get+0x75/0xa0
? selinux_file_open+0x9d/0xf0
ima_file_check+0x64/0x90
path_openat+0x571/0x1720
do_filp_open+0x9b/0x110
? page_counter_try_charge+0x57/0xc0
? files_cgroup_alloc_fd+0x38/0x60
? __alloc_fd+0xd4/0x250
? do_sys_open+0x1bd/0x250
do_sys_open+0x1bd/0x250
do_syscall_64+0x5d/0x1d0
entry_SYSCALL_64_after_hwframe+0x65/0xca
Commit c7423dbdbc9e ("ima: Handle -ESTALE returned by
ima_filter_rule_match()") introduced call to ima_lsm_copy_rule within a
RCU read-side critical section which contains kmalloc with GFP_KERNEL.
This implies a possible sleep and violates limitations of RCU read-side
critical sections on non-PREEMPT systems.
Sleeping within RCU read-side critical section might cause
synchronize_rcu() returning early and break RCU protection, allowing a
UAF to happen.
The root cause of this issue could be described as follows:
| Thread A | Thread B |
| |ima_match_policy |
| | rcu_read_lock |
|ima_lsm_update_rule | |
| synchronize_rcu | |
| | kmalloc(GFP_KERNEL)|
| | sleep |
==> synchronize_rcu returns early
| kfree(entry) | |
| | entry = entry->next|
==> UAF happens and entry now becomes NULL (or could be anything).
| | entry->action |
==> Accessing entry might cause panic.
To fix this issue, we are converting all kmalloc that is called within
RCU read-side critical section to use GFP_ATOMIC.
[PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case] |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix races between hole punching and AIO+DIO
After commit "ocfs2: return real error code in ocfs2_dio_wr_get_block",
fstests/generic/300 become from always failed to sometimes failed:
========================================================================
[ 473.293420 ] run fstests generic/300
[ 475.296983 ] JBD2: Ignoring recovery information on journal
[ 475.302473 ] ocfs2: Mounting device (253,1) on (node local, slot 0) with ordered data mode.
[ 494.290998 ] OCFS2: ERROR (device dm-1): ocfs2_change_extent_flag: Owner 5668 has an extent at cpos 78723 which can no longer be found
[ 494.291609 ] On-disk corruption discovered. Please run fsck.ocfs2 once the filesystem is unmounted.
[ 494.292018 ] OCFS2: File system is now read-only.
[ 494.292224 ] (kworker/19:11,2628,19):ocfs2_mark_extent_written:5272 ERROR: status = -30
[ 494.292602 ] (kworker/19:11,2628,19):ocfs2_dio_end_io_write:2374 ERROR: status = -3
fio: io_u error on file /mnt/scratch/racer: Read-only file system: write offset=460849152, buflen=131072
=========================================================================
In __blockdev_direct_IO, ocfs2_dio_wr_get_block is called to add unwritten
extents to a list. extents are also inserted into extent tree in
ocfs2_write_begin_nolock. Then another thread call fallocate to puch a
hole at one of the unwritten extent. The extent at cpos was removed by
ocfs2_remove_extent(). At end io worker thread, ocfs2_search_extent_list
found there is no such extent at the cpos.
T1 T2 T3
inode lock
...
insert extents
...
inode unlock
ocfs2_fallocate
__ocfs2_change_file_space
inode lock
lock ip_alloc_sem
ocfs2_remove_inode_range inode
ocfs2_remove_btree_range
ocfs2_remove_extent
^---remove the extent at cpos 78723
...
unlock ip_alloc_sem
inode unlock
ocfs2_dio_end_io
ocfs2_dio_end_io_write
lock ip_alloc_sem
ocfs2_mark_extent_written
ocfs2_change_extent_flag
ocfs2_search_extent_list
^---failed to find extent
...
unlock ip_alloc_sem
In most filesystems, fallocate is not compatible with racing with AIO+DIO,
so fix it by adding to wait for all dio before fallocate/punch_hole like
ext4. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/memory-failure: fix handling of dissolved but not taken off from buddy pages
When I did memory failure tests recently, below panic occurs:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8cee00
flags: 0x6fffe0000000000(node=1|zone=2|lastcpupid=0x7fff)
raw: 06fffe0000000000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000009 00000000ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(!PageBuddy(page))
------------[ cut here ]------------
kernel BUG at include/linux/page-flags.h:1009!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
RIP: 0010:__del_page_from_free_list+0x151/0x180
RSP: 0018:ffffa49c90437998 EFLAGS: 00000046
RAX: 0000000000000035 RBX: 0000000000000009 RCX: ffff8dd8dfd1c9c8
RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff8dd8dfd1c9c0
RBP: ffffd901233b8000 R08: ffffffffab5511f8 R09: 0000000000008c69
R10: 0000000000003c15 R11: ffffffffab5511f8 R12: ffff8dd8fffc0c80
R13: 0000000000000001 R14: ffff8dd8fffc0c80 R15: 0000000000000009
FS: 00007ff916304740(0000) GS:ffff8dd8dfd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055eae50124c8 CR3: 00000008479e0000 CR4: 00000000000006f0
Call Trace:
<TASK>
__rmqueue_pcplist+0x23b/0x520
get_page_from_freelist+0x26b/0xe40
__alloc_pages_noprof+0x113/0x1120
__folio_alloc_noprof+0x11/0xb0
alloc_buddy_hugetlb_folio.isra.0+0x5a/0x130
__alloc_fresh_hugetlb_folio+0xe7/0x140
alloc_pool_huge_folio+0x68/0x100
set_max_huge_pages+0x13d/0x340
hugetlb_sysctl_handler_common+0xe8/0x110
proc_sys_call_handler+0x194/0x280
vfs_write+0x387/0x550
ksys_write+0x64/0xe0
do_syscall_64+0xc2/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff916114887
RSP: 002b:00007ffec8a2fd78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000055eae500e350 RCX: 00007ff916114887
RDX: 0000000000000004 RSI: 000055eae500e390 RDI: 0000000000000003
RBP: 000055eae50104c0 R08: 0000000000000000 R09: 000055eae50104c0
R10: 0000000000000077 R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000000004 R14: 00007ff916216b80 R15: 00007ff916216a00
</TASK>
Modules linked in: mce_inject hwpoison_inject
---[ end trace 0000000000000000 ]---
And before the panic, there had an warning about bad page state:
BUG: Bad page state in process page-types pfn:8cee00
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8cee00
flags: 0x6fffe0000000000(node=1|zone=2|lastcpupid=0x7fff)
page_type: 0xffffff7f(buddy)
raw: 06fffe0000000000 ffffd901241c0008 ffffd901240f8008 0000000000000000
raw: 0000000000000000 0000000000000009 00000000ffffff7f 0000000000000000
page dumped because: nonzero mapcount
Modules linked in: mce_inject hwpoison_inject
CPU: 8 PID: 154211 Comm: page-types Not tainted 6.9.0-rc4-00499-g5544ec3178e2-dirty #22
Call Trace:
<TASK>
dump_stack_lvl+0x83/0xa0
bad_page+0x63/0xf0
free_unref_page+0x36e/0x5c0
unpoison_memory+0x50b/0x630
simple_attr_write_xsigned.constprop.0.isra.0+0xb3/0x110
debugfs_attr_write+0x42/0x60
full_proxy_write+0x5b/0x80
vfs_write+0xcd/0x550
ksys_write+0x64/0xe0
do_syscall_64+0xc2/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f189a514887
RSP: 002b:00007ffdcd899718 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f189a514887
RDX: 0000000000000009 RSI: 00007ffdcd899730 RDI: 0000000000000003
RBP: 00007ffdcd8997a0 R08: 0000000000000000 R09: 00007ffdcd8994b2
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdcda199a8
R13: 0000000000404af1 R14: 000000000040ad78 R15: 00007f189a7a5040
</TASK>
The root cause should be the below race:
memory_failure
try_memory_failure_hugetlb
me_huge_page
__page_handle_poison
dissolve_free_hugetlb_folio
drain_all_pages -- Buddy page can be isolated e.g. for compaction.
take_page_off_buddy -- Failed as page is not in the
---truncated--- |
| In Eclipse OpenJ9 before version 0.41.0, the JVM can be forced into an infinite busy hang on a spinlock or a segmentation fault if a shutdown signal (SIGTERM, SIGINT or SIGHUP) is received before the JVM has finished initializing.
|
| An issue was discovered in drivers/bluetooth/hci_ldisc.c in the Linux kernel 6.2. In hci_uart_tty_ioctl, there is a race condition between HCIUARTSETPROTO and HCIUARTGETPROTO. HCI_UART_PROTO_SET is set before hu->proto is set. A NULL pointer dereference may occur. |
| An issue was discovered in the Linux kernel through 6.0.9. drivers/char/xillybus/xillyusb.c has a race condition and use-after-free during physical removal of a USB device. |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period
io_eventfd_do_signal() is invoked from an RCU callback, but when
dropping the reference to the io_ev_fd, it calls io_eventfd_free()
directly if the refcount drops to zero. This isn't correct, as any
potential freeing of the io_ev_fd should be deferred another RCU grace
period.
Just call io_eventfd_put() rather than open-code the dec-and-test and
free, which will correctly defer it another RCU grace period. |
| In the Linux kernel, the following vulnerability has been resolved:
topology: Keep the cpumask unchanged when printing cpumap
During fuzz testing, the following warning was discovered:
different return values (15 and 11) from vsnprintf("%*pbl
", ...)
test:keyward is WARNING in kvasprintf
WARNING: CPU: 55 PID: 1168477 at lib/kasprintf.c:30 kvasprintf+0x121/0x130
Call Trace:
kvasprintf+0x121/0x130
kasprintf+0xa6/0xe0
bitmap_print_to_buf+0x89/0x100
core_siblings_list_read+0x7e/0xb0
kernfs_file_read_iter+0x15b/0x270
new_sync_read+0x153/0x260
vfs_read+0x215/0x290
ksys_read+0xb9/0x160
do_syscall_64+0x56/0x100
entry_SYSCALL_64_after_hwframe+0x78/0xe2
The call trace shows that kvasprintf() reported this warning during the
printing of core_siblings_list. kvasprintf() has several steps:
(1) First, calculate the length of the resulting formatted string.
(2) Allocate a buffer based on the returned length.
(3) Then, perform the actual string formatting.
(4) Check whether the lengths of the formatted strings returned in
steps (1) and (2) are consistent.
If the core_cpumask is modified between steps (1) and (3), the lengths
obtained in these two steps may not match. Indeed our test includes cpu
hotplugging, which should modify core_cpumask while printing.
To fix this issue, cache the cpumask into a temporary variable before
calling cpumap_print_{list, cpumask}_to_buf(), to keep it unchanged
during the printing process. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/dp_mst: Fix resetting msg rx state after topology removal
If the MST topology is removed during the reception of an MST down reply
or MST up request sideband message, the
drm_dp_mst_topology_mgr::up_req_recv/down_rep_recv states could be reset
from one thread via drm_dp_mst_topology_mgr_set_mst(false), racing with
the reading/parsing of the message from another thread via
drm_dp_mst_handle_down_rep() or drm_dp_mst_handle_up_req(). The race is
possible since the reader/parser doesn't hold any lock while accessing
the reception state. This in turn can lead to a memory corruption in the
reader/parser as described by commit bd2fccac61b4 ("drm/dp_mst: Fix MST
sideband message body length check").
Fix the above by resetting the message reception state if needed before
reading/parsing a message. Another solution would be to hold the
drm_dp_mst_topology_mgr::lock for the whole duration of the message
reception/parsing in drm_dp_mst_handle_down_rep() and
drm_dp_mst_handle_up_req(), however this would require a bigger change.
Since the fix is also needed for stable, opting for the simpler solution
in this patch. |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring: check if iowq is killed before queuing
task work can be executed after the task has gone through io_uring
termination, whether it's the final task_work run or the fallback path.
In this case, task work will find ->io_wq being already killed and
null'ed, which is a problem if it then tries to forward the request to
io_queue_iowq(). Make io_queue_iowq() fail requests in this case.
Note that it also checks PF_KTHREAD, because the user can first close
a DEFER_TASKRUN ring and shortly after kill the task, in which case
->iowq check would race. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Fix race between element replace and close()
Element replace (with a socket different from the one stored) may race
with socket's close() link popping & unlinking. __sock_map_delete()
unconditionally unrefs the (wrong) element:
// set map[0] = s0
map_update_elem(map, 0, s0)
// drop fd of s0
close(s0)
sock_map_close()
lock_sock(sk) (s0!)
sock_map_remove_links(sk)
link = sk_psock_link_pop()
sock_map_unlink(sk, link)
sock_map_delete_from_link
// replace map[0] with s1
map_update_elem(map, 0, s1)
sock_map_update_elem
(s1!) lock_sock(sk)
sock_map_update_common
psock = sk_psock(sk)
spin_lock(&stab->lock)
osk = stab->sks[idx]
sock_map_add_link(..., &stab->sks[idx])
sock_map_unref(osk, &stab->sks[idx])
psock = sk_psock(osk)
sk_psock_put(sk, psock)
if (refcount_dec_and_test(&psock))
sk_psock_drop(sk, psock)
spin_unlock(&stab->lock)
unlock_sock(sk)
__sock_map_delete
spin_lock(&stab->lock)
sk = *psk // s1 replaced s0; sk == s1
if (!sk_test || sk_test == sk) // sk_test (s0) != sk (s1); no branch
sk = xchg(psk, NULL)
if (sk)
sock_map_unref(sk, psk) // unref s1; sks[idx] will dangle
psock = sk_psock(sk)
sk_psock_put(sk, psock)
if (refcount_dec_and_test())
sk_psock_drop(sk, psock)
spin_unlock(&stab->lock)
release_sock(sk)
Then close(map) enqueues bpf_map_free_deferred, which finally calls
sock_map_free(). This results in some refcount_t warnings along with
a KASAN splat [1].
Fix __sock_map_delete(), do not allow sock_map_unref() on elements that
may have been replaced.
[1]:
BUG: KASAN: slab-use-after-free in sock_map_free+0x10e/0x330
Write of size 4 at addr ffff88811f5b9100 by task kworker/u64:12/1063
CPU: 14 UID: 0 PID: 1063 Comm: kworker/u64:12 Not tainted 6.12.0+ #125
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
Workqueue: events_unbound bpf_map_free_deferred
Call Trace:
<TASK>
dump_stack_lvl+0x68/0x90
print_report+0x174/0x4f6
kasan_report+0xb9/0x190
kasan_check_range+0x10f/0x1e0
sock_map_free+0x10e/0x330
bpf_map_free_deferred+0x173/0x320
process_one_work+0x846/0x1420
worker_thread+0x5b3/0xf80
kthread+0x29e/0x360
ret_from_fork+0x2d/0x70
ret_from_fork_asm+0x1a/0x30
</TASK>
Allocated by task 1202:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x10/0x30
__kasan_slab_alloc+0x85/0x90
kmem_cache_alloc_noprof+0x131/0x450
sk_prot_alloc+0x5b/0x220
sk_alloc+0x2c/0x870
unix_create1+0x88/0x8a0
unix_create+0xc5/0x180
__sock_create+0x241/0x650
__sys_socketpair+0x1ce/0x420
__x64_sys_socketpair+0x92/0x100
do_syscall_64+0x93/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Freed by task 46:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x10/0x30
kasan_save_free_info+0x37/0x60
__kasan_slab_free+0x4b/0x70
kmem_cache_free+0x1a1/0x590
__sk_destruct+0x388/0x5a0
sk_psock_destroy+0x73e/0xa50
process_one_work+0x846/0x1420
worker_thread+0x5b3/0xf80
kthread+0x29e/0x360
ret_from_fork+0x2d/0x70
ret_from_fork_asm+0x1a/0x30
The bu
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: Hold module reference while requesting a module
User space may unload ip_set.ko while it is itself requesting a set type
backend module, leading to a kernel crash. The race condition may be
provoked by inserting an mdelay() right after the nfnl_unlock() call. |
| In the Linux kernel, the following vulnerability has been resolved:
media: i2c: tc358743: Fix crash in the probe error path when using polling
If an error occurs in the probe() function, we should remove the polling
timer that was alarmed earlier, otherwise the timer is called with
arguments that are already freed, which results in a crash.
------------[ cut here ]------------
WARNING: CPU: 3 PID: 0 at kernel/time/timer.c:1830 __run_timers+0x244/0x268
Modules linked in:
CPU: 3 UID: 0 PID: 0 Comm: swapper/3 Not tainted 6.11.0 #226
Hardware name: Diasom DS-RK3568-SOM-EVB (DT)
pstate: 804000c9 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __run_timers+0x244/0x268
lr : __run_timers+0x1d4/0x268
sp : ffffff80eff2baf0
x29: ffffff80eff2bb50 x28: 7fffffffffffffff x27: ffffff80eff2bb00
x26: ffffffc080f669c0 x25: ffffff80efef6bf0 x24: ffffff80eff2bb00
x23: 0000000000000000 x22: dead000000000122 x21: 0000000000000000
x20: ffffff80efef6b80 x19: ffffff80041c8bf8 x18: ffffffffffffffff
x17: ffffffc06f146000 x16: ffffff80eff27dc0 x15: 000000000000003e
x14: 0000000000000000 x13: 00000000000054da x12: 0000000000000000
x11: 00000000000639c0 x10: 000000000000000c x9 : 0000000000000009
x8 : ffffff80eff2cb40 x7 : ffffff80eff2cb40 x6 : ffffff8002bee480
x5 : ffffffc080cb2220 x4 : ffffffc080cb2150 x3 : 00000000000f4240
x2 : 0000000000000102 x1 : ffffff80eff2bb00 x0 : ffffff80041c8bf0
Call trace:
__run_timers+0x244/0x268
timer_expire_remote+0x50/0x68
tmigr_handle_remote+0x388/0x39c
run_timer_softirq+0x38/0x44
handle_softirqs+0x138/0x298
__do_softirq+0x14/0x20
____do_softirq+0x10/0x1c
call_on_irq_stack+0x24/0x4c
do_softirq_own_stack+0x1c/0x2c
irq_exit_rcu+0x9c/0xcc
el1_interrupt+0x48/0xc0
el1h_64_irq_handler+0x18/0x24
el1h_64_irq+0x7c/0x80
default_idle_call+0x34/0x68
do_idle+0x23c/0x294
cpu_startup_entry+0x38/0x3c
secondary_start_kernel+0x128/0x160
__secondary_switched+0xb8/0xbc
---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/arm-smmu: Defer probe of clients after smmu device bound
Null pointer dereference occurs due to a race between smmu
driver probe and client driver probe, when of_dma_configure()
for client is called after the iommu_device_register() for smmu driver
probe has executed but before the driver_bound() for smmu driver
has been called.
Following is how the race occurs:
T1:Smmu device probe T2: Client device probe
really_probe()
arm_smmu_device_probe()
iommu_device_register()
really_probe()
platform_dma_configure()
of_dma_configure()
of_dma_configure_id()
of_iommu_configure()
iommu_probe_device()
iommu_init_device()
arm_smmu_probe_device()
arm_smmu_get_by_fwnode()
driver_find_device_by_fwnode()
driver_find_device()
next_device()
klist_next()
/* null ptr
assigned to smmu */
/* null ptr dereference
while smmu->streamid_mask */
driver_bound()
klist_add_tail()
When this null smmu pointer is dereferenced later in
arm_smmu_probe_device, the device crashes.
Fix this by deferring the probe of the client device
until the smmu device has bound to the arm smmu driver.
[will: Add comment] |
