| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| Liferay Portal 7.4.0 through 7.4.3.99, and older unsupported versions, and Liferay DXP 2023.Q3.1 through 2023.Q3.4, 7.4 GA through update 92, 7.3 GA through update 34, and older unsupported versions stores password reset tokens in plain text, which allows attackers with access to the database to obtain the token, reset a user’s password and take over the user’s account. |
| CSRF vulnerability in Headless API in Liferay Portal 7.4.0 through 7.4.3.107, and Liferay DXP 2023.Q3.1 through 2023.Q3.4, 7.4 GA through update 92, 7.3 GA through update 35, and older unsupported versions allows remote attackers to execute any Headless API via the `endpoint` parameter. |
| Password enumeration vulnerability in Liferay Portal 7.4.0 through 7.4.3.119, and older unsupported versions, and Liferay DXP 2024.Q1.1 through 2024.Q1.5, 2023.Q4.0 through 2023.Q4.10, 2023.Q3.1 through 2023.Q3.10, 7.4 GA through update 92, and older unsupported versions allows remote attackers to determine a user’s password even if account lockout is enabled via brute force attack. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix BUG_ON() when directory entry has invalid rec_len
The rec_len field in the directory entry has to be a multiple of 4. A
corrupted filesystem image can be used to hit a BUG() in
ext4_rec_len_to_disk(), called from make_indexed_dir().
------------[ cut here ]------------
kernel BUG at fs/ext4/ext4.h:2413!
...
RIP: 0010:make_indexed_dir+0x53f/0x5f0
...
Call Trace:
<TASK>
? add_dirent_to_buf+0x1b2/0x200
ext4_add_entry+0x36e/0x480
ext4_add_nondir+0x2b/0xc0
ext4_create+0x163/0x200
path_openat+0x635/0xe90
do_filp_open+0xb4/0x160
? __create_object.isra.0+0x1de/0x3b0
? _raw_spin_unlock+0x12/0x30
do_sys_openat2+0x91/0x150
__x64_sys_open+0x6c/0xa0
do_syscall_64+0x3c/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
The fix simply adds a call to ext4_check_dir_entry() to validate the
directory entry, returning -EFSCORRUPTED if the entry is invalid. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
Reject kvm_gpc_check() and kvm_gpc_refresh() if the cache is inactive.
Not checking the active flag during refresh is particularly egregious, as
KVM can end up with a valid, inactive cache, which can lead to a variety
of use-after-free bugs, e.g. consuming a NULL kernel pointer or missing
an mmu_notifier invalidation due to the cache not being on the list of
gfns to invalidate.
Note, "active" needs to be set if and only if the cache is on the list
of caches, i.e. is reachable via mmu_notifier events. If a relevant
mmu_notifier event occurs while the cache is "active" but not on the
list, KVM will not acquire the cache's lock and so will not serailize
the mmu_notifier event with active users and/or kvm_gpc_refresh().
A race between KVM_XEN_ATTR_TYPE_SHARED_INFO and KVM_XEN_HVM_EVTCHN_SEND
can be exploited to trigger the bug.
1. Deactivate shinfo cache:
kvm_xen_hvm_set_attr
case KVM_XEN_ATTR_TYPE_SHARED_INFO
kvm_gpc_deactivate
kvm_gpc_unmap
gpc->valid = false
gpc->khva = NULL
gpc->active = false
Result: active = false, valid = false
2. Cause cache refresh:
kvm_arch_vm_ioctl
case KVM_XEN_HVM_EVTCHN_SEND
kvm_xen_hvm_evtchn_send
kvm_xen_set_evtchn
kvm_xen_set_evtchn_fast
kvm_gpc_check
return -EWOULDBLOCK because !gpc->valid
kvm_xen_set_evtchn_fast
return -EWOULDBLOCK
kvm_gpc_refresh
hva_to_pfn_retry
gpc->valid = true
gpc->khva = not NULL
Result: active = false, valid = true
3. Race ioctl KVM_XEN_HVM_EVTCHN_SEND against ioctl
KVM_XEN_ATTR_TYPE_SHARED_INFO:
kvm_arch_vm_ioctl
case KVM_XEN_HVM_EVTCHN_SEND
kvm_xen_hvm_evtchn_send
kvm_xen_set_evtchn
kvm_xen_set_evtchn_fast
read_lock gpc->lock
kvm_xen_hvm_set_attr case
KVM_XEN_ATTR_TYPE_SHARED_INFO
mutex_lock kvm->lock
kvm_xen_shared_info_init
kvm_gpc_activate
gpc->khva = NULL
kvm_gpc_check
[ Check passes because gpc->valid is
still true, even though gpc->khva
is already NULL. ]
shinfo = gpc->khva
pending_bits = shinfo->evtchn_pending
CRASH: test_and_set_bit(..., pending_bits) |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: smm: number of GPRs in the SMRAM image depends on the image format
On 64 bit host, if the guest doesn't have X86_FEATURE_LM, KVM will
access 16 gprs to 32-bit smram image, causing out-ouf-bound ram
access.
On 32 bit host, the rsm_load_state_64/enter_smm_save_state_64
is compiled out, thus access overflow can't happen. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Initialize gfn_to_pfn_cache locks in dedicated helper
Move the gfn_to_pfn_cache lock initialization to another helper and
call the new helper during VM/vCPU creation. There are race
conditions possible due to kvm_gfn_to_pfn_cache_init()'s
ability to re-initialize the cache's locks.
For example: a race between ioctl(KVM_XEN_HVM_EVTCHN_SEND) and
kvm_gfn_to_pfn_cache_init() leads to a corrupted shinfo gpc lock.
(thread 1) | (thread 2)
|
kvm_xen_set_evtchn_fast |
read_lock_irqsave(&gpc->lock, ...) |
| kvm_gfn_to_pfn_cache_init
| rwlock_init(&gpc->lock)
read_unlock_irqrestore(&gpc->lock, ...) |
Rename "cache_init" and "cache_destroy" to activate+deactivate to
avoid implying that the cache really is destroyed/freed.
Note, there more races in the newly named kvm_gpc_activate() that will
be addressed separately.
[sean: call out that this is a bug fix] |
| In the Linux kernel, the following vulnerability has been resolved:
x86/tdx: Panic on bad configs that #VE on "private" memory access
All normal kernel memory is "TDX private memory". This includes
everything from kernel stacks to kernel text. Handling
exceptions on arbitrary accesses to kernel memory is essentially
impossible because they can happen in horribly nasty places like
kernel entry/exit. But, TDX hardware can theoretically _deliver_
a virtualization exception (#VE) on any access to private memory.
But, it's not as bad as it sounds. TDX can be configured to never
deliver these exceptions on private memory with a "TD attribute"
called ATTR_SEPT_VE_DISABLE. The guest has no way to *set* this
attribute, but it can check it.
Ensure ATTR_SEPT_VE_DISABLE is set in early boot. panic() if it
is unset. There is no sane way for Linux to run with this
attribute clear so a panic() is appropriate.
There's small window during boot before the check where kernel
has an early #VE handler. But the handler is only for port I/O
and will also panic() as soon as it sees any other #VE, such as
a one generated by a private memory access.
[ dhansen: Rewrite changelog and rebase on new tdx_parse_tdinfo().
Add Kirill's tested-by because I made changes since
he wrote this. ] |
| In the Linux kernel, the following vulnerability has been resolved:
cxl/region: Fix cxl_region leak, cleanup targets at region delete
When a region is deleted any targets that have been previously assigned
to that region hold references to it. Trigger those references to
drop by detaching all targets at unregister_region() time.
Otherwise that region object will leak as userspace has lost the ability
to detach targets once region sysfs is torn down. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix tree mod log mishandling of reallocated nodes
We have been seeing the following panic in production
kernel BUG at fs/btrfs/tree-mod-log.c:677!
invalid opcode: 0000 [#1] SMP
RIP: 0010:tree_mod_log_rewind+0x1b4/0x200
RSP: 0000:ffffc9002c02f890 EFLAGS: 00010293
RAX: 0000000000000003 RBX: ffff8882b448c700 RCX: 0000000000000000
RDX: 0000000000008000 RSI: 00000000000000a7 RDI: ffff88877d831c00
RBP: 0000000000000002 R08: 000000000000009f R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000100c40 R12: 0000000000000001
R13: ffff8886c26d6a00 R14: ffff88829f5424f8 R15: ffff88877d831a00
FS: 00007fee1d80c780(0000) GS:ffff8890400c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fee1963a020 CR3: 0000000434f33002 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
btrfs_get_old_root+0x12b/0x420
btrfs_search_old_slot+0x64/0x2f0
? tree_mod_log_oldest_root+0x3d/0xf0
resolve_indirect_ref+0xfd/0x660
? ulist_alloc+0x31/0x60
? kmem_cache_alloc_trace+0x114/0x2c0
find_parent_nodes+0x97a/0x17e0
? ulist_alloc+0x30/0x60
btrfs_find_all_roots_safe+0x97/0x150
iterate_extent_inodes+0x154/0x370
? btrfs_search_path_in_tree+0x240/0x240
iterate_inodes_from_logical+0x98/0xd0
? btrfs_search_path_in_tree+0x240/0x240
btrfs_ioctl_logical_to_ino+0xd9/0x180
btrfs_ioctl+0xe2/0x2ec0
? __mod_memcg_lruvec_state+0x3d/0x280
? do_sys_openat2+0x6d/0x140
? kretprobe_dispatcher+0x47/0x70
? kretprobe_rethook_handler+0x38/0x50
? rethook_trampoline_handler+0x82/0x140
? arch_rethook_trampoline_callback+0x3b/0x50
? kmem_cache_free+0xfb/0x270
? do_sys_openat2+0xd5/0x140
__x64_sys_ioctl+0x71/0xb0
do_syscall_64+0x2d/0x40
Which is this code in tree_mod_log_rewind()
switch (tm->op) {
case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING:
BUG_ON(tm->slot < n);
This occurs because we replay the nodes in order that they happened, and
when we do a REPLACE we will log a REMOVE_WHILE_FREEING for every slot,
starting at 0. 'n' here is the number of items in this block, which in
this case was 1, but we had 2 REMOVE_WHILE_FREEING operations.
The actual root cause of this was that we were replaying operations for
a block that shouldn't have been replayed. Consider the following
sequence of events
1. We have an already modified root, and we do a btrfs_get_tree_mod_seq().
2. We begin removing items from this root, triggering KEY_REPLACE for
it's child slots.
3. We remove one of the 2 children this root node points to, thus triggering
the root node promotion of the remaining child, and freeing this node.
4. We modify a new root, and re-allocate the above node to the root node of
this other root.
The tree mod log looks something like this
logical 0 op KEY_REPLACE (slot 1) seq 2
logical 0 op KEY_REMOVE (slot 1) seq 3
logical 0 op KEY_REMOVE_WHILE_FREEING (slot 0) seq 4
logical 4096 op LOG_ROOT_REPLACE (old logical 0) seq 5
logical 8192 op KEY_REMOVE_WHILE_FREEING (slot 1) seq 6
logical 8192 op KEY_REMOVE_WHILE_FREEING (slot 0) seq 7
logical 0 op LOG_ROOT_REPLACE (old logical 8192) seq 8
>From here the bug is triggered by the following steps
1. Call btrfs_get_old_root() on the new_root.
2. We call tree_mod_log_oldest_root(btrfs_root_node(new_root)), which is
currently logical 0.
3. tree_mod_log_oldest_root() calls tree_mod_log_search_oldest(), which
gives us the KEY_REPLACE seq 2, and since that's not a
LOG_ROOT_REPLACE we incorrectly believe that we don't have an old
root, because we expect that the most recent change should be a
LOG_ROOT_REPLACE.
4. Back in tree_mod_log_oldest_root() we don't have a LOG_ROOT_REPLACE,
so we don't set old_root, we simply use our e
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
i2c: piix4: Fix adapter not be removed in piix4_remove()
In piix4_probe(), the piix4 adapter will be registered in:
piix4_probe()
piix4_add_adapters_sb800() / piix4_add_adapter()
i2c_add_adapter()
Based on the probed device type, piix4_add_adapters_sb800() or single
piix4_add_adapter() will be called.
For the former case, piix4_adapter_count is set as the number of adapters,
while for antoher case it is not set and kept default *zero*.
When piix4 is removed, piix4_remove() removes the adapters added in
piix4_probe(), basing on the piix4_adapter_count value.
Because the count is zero for the single adapter case, the adapter won't
be removed and makes the sources allocated for adapter leaked, such as
the i2c client and device.
These sources can still be accessed by i2c or bus and cause problems.
An easily reproduced case is that if a new adapter is registered, i2c
will get the leaked adapter and try to call smbus_algorithm, which was
already freed:
Triggered by: rmmod i2c_piix4 && modprobe max31730
BUG: unable to handle page fault for address: ffffffffc053d860
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3752 Comm: modprobe Tainted: G
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
RIP: 0010:i2c_default_probe (drivers/i2c/i2c-core-base.c:2259) i2c_core
RSP: 0018:ffff888107477710 EFLAGS: 00000246
...
<TASK>
i2c_detect (drivers/i2c/i2c-core-base.c:2302) i2c_core
__process_new_driver (drivers/i2c/i2c-core-base.c:1336) i2c_core
bus_for_each_dev (drivers/base/bus.c:301)
i2c_for_each_dev (drivers/i2c/i2c-core-base.c:1823) i2c_core
i2c_register_driver (drivers/i2c/i2c-core-base.c:1861) i2c_core
do_one_initcall (init/main.c:1296)
do_init_module (kernel/module/main.c:2455)
...
</TASK>
---[ end trace 0000000000000000 ]---
Fix this problem by correctly set piix4_adapter_count as 1 for the
single adapter so it can be normally removed. |
| An issue was discovered in AnyDesk through 9.0.4. Remote Denial of Service can occur because of incorrect deserialization that results in failed memory allocation and a NULL pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: ti: am65-cpsw: Fix segmentation fault at module unload
Move am65_cpsw_nuss_phylink_cleanup() call to after
am65_cpsw_nuss_cleanup_ndev() so phylink is still valid
to prevent the below Segmentation fault on module remove when
first slave link is up.
[ 31.652944] Unable to handle kernel paging request at virtual address 00040008000005f4
[ 31.684627] Mem abort info:
[ 31.687446] ESR = 0x0000000096000004
[ 31.704614] EC = 0x25: DABT (current EL), IL = 32 bits
[ 31.720663] SET = 0, FnV = 0
[ 31.723729] EA = 0, S1PTW = 0
[ 31.740617] FSC = 0x04: level 0 translation fault
[ 31.756624] Data abort info:
[ 31.759508] ISV = 0, ISS = 0x00000004
[ 31.776705] CM = 0, WnR = 0
[ 31.779695] [00040008000005f4] address between user and kernel address ranges
[ 31.808644] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[ 31.814928] Modules linked in: wlcore_sdio wl18xx wlcore mac80211 libarc4 cfg80211 rfkill crct10dif_ce phy_gmii_sel ti_am65_cpsw_nuss(-) sch_fq_codel ipv6
[ 31.828776] CPU: 0 PID: 1026 Comm: modprobe Not tainted 6.1.0-rc2-00012-gfabfcf7dafdb-dirty #160
[ 31.837547] Hardware name: Texas Instruments AM625 (DT)
[ 31.842760] pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 31.849709] pc : phy_stop+0x18/0xf8
[ 31.853202] lr : phylink_stop+0x38/0xf8
[ 31.857031] sp : ffff80000a0839f0
[ 31.860335] x29: ffff80000a0839f0 x28: ffff000000de1c80 x27: 0000000000000000
[ 31.867462] x26: 0000000000000000 x25: 0000000000000000 x24: ffff80000a083b98
[ 31.874589] x23: 0000000000000800 x22: 0000000000000001 x21: ffff000001bfba90
[ 31.881715] x20: ffff0000015ee000 x19: 0004000800000200 x18: 0000000000000000
[ 31.888842] x17: ffff800076c45000 x16: ffff800008004000 x15: 000058e39660b106
[ 31.895969] x14: 0000000000000144 x13: 0000000000000144 x12: 0000000000000000
[ 31.903095] x11: 000000000000275f x10: 00000000000009e0 x9 : ffff80000a0837d0
[ 31.910222] x8 : ffff000000de26c0 x7 : ffff00007fbd6540 x6 : ffff00007fbd64c0
[ 31.917349] x5 : ffff00007fbd0b10 x4 : ffff00007fbd0b10 x3 : ffff00007fbd3920
[ 31.924476] x2 : d0a07fcff8b8d500 x1 : 0000000000000000 x0 : 0004000800000200
[ 31.931603] Call trace:
[ 31.934042] phy_stop+0x18/0xf8
[ 31.937177] phylink_stop+0x38/0xf8
[ 31.940657] am65_cpsw_nuss_ndo_slave_stop+0x28/0x1e0 [ti_am65_cpsw_nuss]
[ 31.947452] __dev_close_many+0xa4/0x140
[ 31.951371] dev_close_many+0x84/0x128
[ 31.955115] unregister_netdevice_many+0x130/0x6d0
[ 31.959897] unregister_netdevice_queue+0x94/0xd8
[ 31.964591] unregister_netdev+0x24/0x38
[ 31.968504] am65_cpsw_nuss_cleanup_ndev.isra.0+0x48/0x70 [ti_am65_cpsw_nuss]
[ 31.975637] am65_cpsw_nuss_remove+0x58/0xf8 [ti_am65_cpsw_nuss] |
| In the Linux kernel, the following vulnerability has been resolved:
serial: imx: Add missing .thaw_noirq hook
The following warning is seen with non-console UART instance when
system hibernates.
[ 37.371969] ------------[ cut here ]------------
[ 37.376599] uart3_root_clk already disabled
[ 37.380810] WARNING: CPU: 0 PID: 296 at drivers/clk/clk.c:952 clk_core_disable+0xa4/0xb0
...
[ 37.506986] Call trace:
[ 37.509432] clk_core_disable+0xa4/0xb0
[ 37.513270] clk_disable+0x34/0x50
[ 37.516672] imx_uart_thaw+0x38/0x5c
[ 37.520250] platform_pm_thaw+0x30/0x6c
[ 37.524089] dpm_run_callback.constprop.0+0x3c/0xd4
[ 37.528972] device_resume+0x7c/0x160
[ 37.532633] dpm_resume+0xe8/0x230
[ 37.536036] hibernation_snapshot+0x288/0x430
[ 37.540397] hibernate+0x10c/0x2e0
[ 37.543798] state_store+0xc4/0xd0
[ 37.547203] kobj_attr_store+0x1c/0x30
[ 37.550953] sysfs_kf_write+0x48/0x60
[ 37.554619] kernfs_fop_write_iter+0x118/0x1ac
[ 37.559063] new_sync_write+0xe8/0x184
[ 37.562812] vfs_write+0x230/0x290
[ 37.566214] ksys_write+0x68/0xf4
[ 37.569529] __arm64_sys_write+0x20/0x2c
[ 37.573452] invoke_syscall.constprop.0+0x50/0xf0
[ 37.578156] do_el0_svc+0x11c/0x150
[ 37.581648] el0_svc+0x30/0x140
[ 37.584792] el0t_64_sync_handler+0xe8/0xf0
[ 37.588976] el0t_64_sync+0x1a0/0x1a4
[ 37.592639] ---[ end trace 56e22eec54676d75 ]---
On hibernating, pm core calls into related hooks in sequence like:
.freeze
.freeze_noirq
.thaw_noirq
.thaw
With .thaw_noirq hook being absent, the clock will be disabled in a
unbalanced call which results the warning above.
imx_uart_freeze()
clk_prepare_enable()
imx_uart_suspend_noirq()
clk_disable()
imx_uart_thaw
clk_disable_unprepare()
Adding the missing .thaw_noirq hook as imx_uart_resume_noirq() will have
the call sequence corrected as below and thus fix the warning.
imx_uart_freeze()
clk_prepare_enable()
imx_uart_suspend_noirq()
clk_disable()
imx_uart_resume_noirq()
clk_enable()
imx_uart_thaw
clk_disable_unprepare() |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: clear out_curr if all frag chunks of current msg are pruned
A crash was reported by Zhen Chen:
list_del corruption, ffffa035ddf01c18->next is NULL
WARNING: CPU: 1 PID: 250682 at lib/list_debug.c:49 __list_del_entry_valid+0x59/0xe0
RIP: 0010:__list_del_entry_valid+0x59/0xe0
Call Trace:
sctp_sched_dequeue_common+0x17/0x70 [sctp]
sctp_sched_fcfs_dequeue+0x37/0x50 [sctp]
sctp_outq_flush_data+0x85/0x360 [sctp]
sctp_outq_uncork+0x77/0xa0 [sctp]
sctp_cmd_interpreter.constprop.0+0x164/0x1450 [sctp]
sctp_side_effects+0x37/0xe0 [sctp]
sctp_do_sm+0xd0/0x230 [sctp]
sctp_primitive_SEND+0x2f/0x40 [sctp]
sctp_sendmsg_to_asoc+0x3fa/0x5c0 [sctp]
sctp_sendmsg+0x3d5/0x440 [sctp]
sock_sendmsg+0x5b/0x70
and in sctp_sched_fcfs_dequeue() it dequeued a chunk from stream
out_curr outq while this outq was empty.
Normally stream->out_curr must be set to NULL once all frag chunks of
current msg are dequeued, as we can see in sctp_sched_dequeue_done().
However, in sctp_prsctp_prune_unsent() as it is not a proper dequeue,
sctp_sched_dequeue_done() is not called to do this.
This patch is to fix it by simply setting out_curr to NULL when the
last frag chunk of current msg is dequeued from out_curr stream in
sctp_prsctp_prune_unsent(). |
| In the Linux kernel, the following vulnerability has been resolved:
siox: fix possible memory leak in siox_device_add()
If device_register() returns error in siox_device_add(),
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(), and sdevice is freed in siox_device_release(),
set it to null in error path. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: zoned: clone zoned device info when cloning a device
When cloning a btrfs_device, we're not cloning the associated
btrfs_zoned_device_info structure of the device in case of a zoned
filesystem.
Later on this leads to a NULL pointer dereference when accessing the
device's zone_info for instance when setting a zone as active.
This was uncovered by fstests' testcase btrfs/161. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: fix potential memleak in 'add_widget_node'
As 'kobject_add' may allocated memory for 'kobject->name' when return error.
And in this function, if call 'kobject_add' failed didn't free kobject.
So call 'kobject_put' to recycling resources. |
| In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix use-after-free bug of ns_writer on remount
If a nilfs2 filesystem is downgraded to read-only due to metadata
corruption on disk and is remounted read/write, or if emergency read-only
remount is performed, detaching a log writer and synchronizing the
filesystem can be done at the same time.
In these cases, use-after-free of the log writer (hereinafter
nilfs->ns_writer) can happen as shown in the scenario below:
Task1 Task2
-------------------------------- ------------------------------
nilfs_construct_segment
nilfs_segctor_sync
init_wait
init_waitqueue_entry
add_wait_queue
schedule
nilfs_remount (R/W remount case)
nilfs_attach_log_writer
nilfs_detach_log_writer
nilfs_segctor_destroy
kfree
finish_wait
_raw_spin_lock_irqsave
__raw_spin_lock_irqsave
do_raw_spin_lock
debug_spin_lock_before <-- use-after-free
While Task1 is sleeping, nilfs->ns_writer is freed by Task2. After Task1
waked up, Task1 accesses nilfs->ns_writer which is already freed. This
scenario diagram is based on the Shigeru Yoshida's post [1].
This patch fixes the issue by not detaching nilfs->ns_writer on remount so
that this UAF race doesn't happen. Along with this change, this patch
also inserts a few necessary read-only checks with superblock instance
where only the ns_writer pointer was used to check if the filesystem is
read-only. |
| In the Linux kernel, the following vulnerability has been resolved:
xsk: Fix race condition in AF_XDP generic RX path
Move rx_lock from xsk_socket to xsk_buff_pool.
Fix synchronization for shared umem mode in
generic RX path where multiple sockets share
single xsk_buff_pool.
RX queue is exclusive to xsk_socket, while FILL
queue can be shared between multiple sockets.
This could result in race condition where two
CPU cores access RX path of two different sockets
sharing the same umem.
Protect both queues by acquiring spinlock in shared
xsk_buff_pool.
Lock contention may be minimized in the future by some
per-thread FQ buffering.
It's safe and necessary to move spin_lock_bh(rx_lock)
after xsk_rcv_check():
* xs->pool and spinlock_init is synchronized by
xsk_bind() -> xsk_is_bound() memory barriers.
* xsk_rcv_check() may return true at the moment
of xsk_release() or xsk_unbind_dev(),
however this will not cause any data races or
race conditions. xsk_unbind_dev() removes xdp
socket from all maps and waits for completion
of all outstanding rx operations. Packets in
RX path will either complete safely or drop. |
