Linux: >> Linux Kernel >> 5.15.167 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
net/sched: teql: Fix double-free in teql_master_xmit
Whenever a TEQL devices has a lockless Qdisc as root, qdisc_reset should
be called using the seq_lock to avoid racing with the datapath. Failure
to do so may cause crashes like the following:
[ 238.028993][ T318] BUG: KASAN: double-free in skb_release_data (net/core/skbuff.c:1139)
[ 238.029328][ T318] Free of addr ffff88810c67ec00 by task poc_teql_uaf_ke/318
[ 238.029749][ T318]
[ 238.029900][ T318] CPU: 3 UID: 0 PID: 318 Comm: poc_teql_ke Not tainted 7.0.0-rc3-00149-ge5b31d988a41 #704 PREEMPT(full)
[ 238.029906][ T318] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 238.029910][ T318] Call Trace:
[ 238.029913][ T318] <TASK>
[ 238.029916][ T318] dump_stack_lvl (lib/dump_stack.c:122)
[ 238.029928][ T318] print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)
[ 238.029940][ T318] ? skb_release_data (net/core/skbuff.c:1139)
[ 238.029944][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
...
[ 238.029957][ T318] ? skb_release_data (net/core/skbuff.c:1139)
[ 238.029969][ T318] kasan_report_invalid_free (mm/kasan/report.c:221 mm/kasan/report.c:563)
[ 238.029979][ T318] ? skb_release_data (net/core/skbuff.c:1139)
[ 238.029989][ T318] check_slab_allocation (mm/kasan/common.c:231)
[ 238.029995][ T318] kmem_cache_free (mm/slub.c:2637 (discriminator 1) mm/slub.c:6168 (discriminator 1) mm/slub.c:6298 (discriminator 1))
[ 238.030004][ T318] skb_release_data (net/core/skbuff.c:1139)
...
[ 238.030025][ T318] sk_skb_reason_drop (net/core/skbuff.c:1256)
[ 238.030032][ T318] pfifo_fast_reset (./include/linux/ptr_ring.h:171 ./include/linux/ptr_ring.h:309 ./include/linux/skb_array.h:98 net/sched/sch_generic.c:827)
[ 238.030039][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
...
[ 238.030054][ T318] qdisc_reset (net/sched/sch_generic.c:1034)
[ 238.030062][ T318] teql_destroy (./include/linux/spinlock.h:395 net/sched/sch_teql.c:157)
[ 238.030071][ T318] __qdisc_destroy (./include/net/pkt_sched.h:328 net/sched/sch_generic.c:1077)
[ 238.030077][ T318] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159)
[ 238.030089][ T318] ? __pfx_qdisc_graft (net/sched/sch_api.c:1091)
[ 238.030095][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 238.030102][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 238.030106][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[ 238.030114][ T318] tc_get_qdisc (net/sched/sch_api.c:1529 net/sched/sch_api.c:1556)
...
[ 238.072958][ T318] Allocated by task 303 on cpu 5 at 238.026275s:
[ 238.073392][ T318] kasan_save_stack (mm/kasan/common.c:58)
[ 238.073884][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5))
[ 238.074230][ T318] __kasan_slab_alloc (mm/kasan/common.c:369)
[ 238.074578][ T318] kmem_cache_alloc_node_noprof (./include/linux/kasan.h:253 mm/slub.c:4542 mm/slub.c:4869 mm/slub.c:4921)
[ 238.076091][ T318] kmalloc_reserve (net/core/skbuff.c:616 (discriminator 107))
[ 238.076450][ T318] __alloc_skb (net/core/skbuff.c:713)
[ 238.076834][ T318] alloc_skb_with_frags (./include/linux/skbuff.h:1383 net/core/skbuff.c:6763)
[ 238.077178][ T318] sock_alloc_send_pskb (net/core/sock.c:2997)
[ 238.077520][ T318] packet_sendmsg (net/packet/af_packet.c:2926 net/packet/af_packet.c:3019 net/packet/af_packet.c:3108)
[ 238.081469][ T318]
[ 238.081870][ T318] Freed by task 299 on cpu 1 at 238.028496s:
[ 238.082761][ T318] kasan_save_stack (mm/kasan/common.c:58)
[ 238.083481][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5))
[ 238.085348][ T318] kasan_save_free_info (mm/kasan/generic.c:587 (discriminator 1))
[ 238.085900][ T318] __kasan_slab_free (mm/
---truncated---
CVSS Score
7.8
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
PM: runtime: Fix a race condition related to device removal
The following code in pm_runtime_work() may dereference the dev->parent
pointer after the parent device has been freed:
/* Maybe the parent is now able to suspend. */
if (parent && !parent->power.ignore_children) {
spin_unlock(&dev->power.lock);
spin_lock(&parent->power.lock);
rpm_idle(parent, RPM_ASYNC);
spin_unlock(&parent->power.lock);
spin_lock(&dev->power.lock);
}
Fix this by inserting a flush_work() call in pm_runtime_remove().
Without this patch blktest block/001 triggers the following complaint
sporadically:
BUG: KASAN: slab-use-after-free in lock_acquire+0x70/0x160
Read of size 1 at addr ffff88812bef7198 by task kworker/u553:1/3081
Workqueue: pm pm_runtime_work
Call Trace:
<TASK>
dump_stack_lvl+0x61/0x80
print_address_description.constprop.0+0x8b/0x310
print_report+0xfd/0x1d7
kasan_report+0xd8/0x1d0
__kasan_check_byte+0x42/0x60
lock_acquire.part.0+0x38/0x230
lock_acquire+0x70/0x160
_raw_spin_lock+0x36/0x50
rpm_suspend+0xc6a/0xfe0
rpm_idle+0x578/0x770
pm_runtime_work+0xee/0x120
process_one_work+0xde3/0x1410
worker_thread+0x5eb/0xfe0
kthread+0x37b/0x480
ret_from_fork+0x6cb/0x920
ret_from_fork_asm+0x11/0x20
</TASK>
Allocated by task 4314:
kasan_save_stack+0x2a/0x50
kasan_save_track+0x18/0x40
kasan_save_alloc_info+0x3d/0x50
__kasan_kmalloc+0xa0/0xb0
__kmalloc_noprof+0x311/0x990
scsi_alloc_target+0x122/0xb60 [scsi_mod]
__scsi_scan_target+0x101/0x460 [scsi_mod]
scsi_scan_channel+0x179/0x1c0 [scsi_mod]
scsi_scan_host_selected+0x259/0x2d0 [scsi_mod]
store_scan+0x2d2/0x390 [scsi_mod]
dev_attr_store+0x43/0x80
sysfs_kf_write+0xde/0x140
kernfs_fop_write_iter+0x3ef/0x670
vfs_write+0x506/0x1470
ksys_write+0xfd/0x230
__x64_sys_write+0x76/0xc0
x64_sys_call+0x213/0x1810
do_syscall_64+0xee/0xfc0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Freed by task 4314:
kasan_save_stack+0x2a/0x50
kasan_save_track+0x18/0x40
kasan_save_free_info+0x3f/0x50
__kasan_slab_free+0x67/0x80
kfree+0x225/0x6c0
scsi_target_dev_release+0x3d/0x60 [scsi_mod]
device_release+0xa3/0x220
kobject_cleanup+0x105/0x3a0
kobject_put+0x72/0xd0
put_device+0x17/0x20
scsi_device_dev_release+0xacf/0x12c0 [scsi_mod]
device_release+0xa3/0x220
kobject_cleanup+0x105/0x3a0
kobject_put+0x72/0xd0
put_device+0x17/0x20
scsi_device_put+0x7f/0xc0 [scsi_mod]
sdev_store_delete+0xa5/0x120 [scsi_mod]
dev_attr_store+0x43/0x80
sysfs_kf_write+0xde/0x140
kernfs_fop_write_iter+0x3ef/0x670
vfs_write+0x506/0x1470
ksys_write+0xfd/0x230
__x64_sys_write+0x76/0xc0
x64_sys_call+0x213/0x1810
CVSS Score
4.7
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
net: mana: fix use-after-free in mana_hwc_destroy_channel() by reordering teardown
A potential race condition exists in mana_hwc_destroy_channel() where
hwc->caller_ctx is freed before the HWC's Completion Queue (CQ) and
Event Queue (EQ) are destroyed. This allows an in-flight CQ interrupt
handler to dereference freed memory, leading to a use-after-free or
NULL pointer dereference in mana_hwc_handle_resp().
mana_smc_teardown_hwc() signals the hardware to stop but does not
synchronize against IRQ handlers already executing on other CPUs. The
IRQ synchronization only happens in mana_hwc_destroy_cq() via
mana_gd_destroy_eq() -> mana_gd_deregister_irq(). Since this runs
after kfree(hwc->caller_ctx), a concurrent mana_hwc_rx_event_handler()
can dereference freed caller_ctx (and rxq->msg_buf) in
mana_hwc_handle_resp().
Fix this by reordering teardown to reverse-of-creation order: destroy
the TX/RX work queues and CQ/EQ before freeing hwc->caller_ctx. This
ensures all in-flight interrupt handlers complete before the memory they
access is freed.
CVSS Score
7.0
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
net: usb: aqc111: Do not perform PM inside suspend callback
syzbot reports "task hung in rpm_resume"
This is caused by aqc111_suspend calling
the PM variant of its write_cmd routine.
The simplified call trace looks like this:
rpm_suspend()
usb_suspend_both() - here udev->dev.power.runtime_status == RPM_SUSPENDING
aqc111_suspend() - called for the usb device interface
aqc111_write32_cmd()
usb_autopm_get_interface()
pm_runtime_resume_and_get()
rpm_resume() - here we call rpm_resume() on our parent
rpm_resume() - Here we wait for a status change that will never happen.
At this point we block another task which holds
rtnl_lock and locks up the whole networking stack.
Fix this by replacing the write_cmd calls with their _nopm variants
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
net: usb: cdc_ncm: add ndpoffset to NDP32 nframes bounds check
The same bounds-check bug fixed for NDP16 in the previous patch also
exists in cdc_ncm_rx_verify_ndp32(). The DPE array size is validated
against the total skb length without accounting for ndpoffset, allowing
out-of-bounds reads when the NDP32 is placed near the end of the NTB.
Add ndpoffset to the nframes bounds check and use struct_size_t() to
express the NDP-plus-DPE-array size more clearly.
Compile-tested only.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
net: usb: cdc_ncm: add ndpoffset to NDP16 nframes bounds check
cdc_ncm_rx_verify_ndp16() validates that the NDP header and its DPE
entries fit within the skb. The first check correctly accounts for
ndpoffset:
if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len)
but the second check omits it:
if ((sizeof(struct usb_cdc_ncm_ndp16) +
ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len)
This validates the DPE array size against the total skb length as if
the NDP were at offset 0, rather than at ndpoffset. When the NDP is
placed near the end of the NTB (large wNdpIndex), the DPE entries can
extend past the skb data buffer even though the check passes.
cdc_ncm_rx_fixup() then reads out-of-bounds memory when iterating
the DPE array.
Add ndpoffset to the nframes bounds check and use struct_size_t() to
express the NDP-plus-DPE-array size more clearly.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
ipv6: add NULL checks for idev in SRv6 paths
__in6_dev_get() can return NULL when the device has no IPv6 configuration
(e.g. MTU < IPV6_MIN_MTU or after NETDEV_UNREGISTER).
Add NULL checks for idev returned by __in6_dev_get() in both
seg6_hmac_validate_skb() and ipv6_srh_rcv() to prevent potential NULL
pointer dereferences.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure
ieee80211_tx_prepare_skb() has three error paths, but only two of them
free the skb. The first error path (ieee80211_tx_prepare() returning
TX_DROP) does not free it, while invoke_tx_handlers() failure and the
fragmentation check both do.
Add kfree_skb() to the first error path so all three are consistent,
and remove the now-redundant frees in callers (ath9k, mt76,
mac80211_hwsim) to avoid double-free.
Document the skb ownership guarantee in the function's kdoc.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
net: mvpp2: guard flow control update with global_tx_fc in buffer switching
mvpp2_bm_switch_buffers() unconditionally calls
mvpp2_bm_pool_update_priv_fc() when switching between per-cpu and
shared buffer pool modes. This function programs CM3 flow control
registers via mvpp2_cm3_read()/mvpp2_cm3_write(), which dereference
priv->cm3_base without any NULL check.
When the CM3 SRAM resource is not present in the device tree (the
third reg entry added by commit 60523583b07c ("dts: marvell: add CM3
SRAM memory to cp11x ethernet device tree")), priv->cm3_base remains
NULL and priv->global_tx_fc is false. Any operation that triggers
mvpp2_bm_switch_buffers(), for example an MTU change that crosses
the jumbo frame threshold, will crash:
Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000000
Mem abort info:
ESR = 0x0000000096000006
EC = 0x25: DABT (current EL), IL = 32 bits
pc : readl+0x0/0x18
lr : mvpp2_cm3_read.isra.0+0x14/0x20
Call trace:
readl+0x0/0x18
mvpp2_bm_pool_update_fc+0x40/0x12c
mvpp2_bm_pool_update_priv_fc+0x94/0xd8
mvpp2_bm_switch_buffers.isra.0+0x80/0x1c0
mvpp2_change_mtu+0x140/0x380
__dev_set_mtu+0x1c/0x38
dev_set_mtu_ext+0x78/0x118
dev_set_mtu+0x48/0xa8
dev_ifsioc+0x21c/0x43c
dev_ioctl+0x2d8/0x42c
sock_ioctl+0x314/0x378
Every other flow control call site in the driver already guards
hardware access with either priv->global_tx_fc or port->tx_fc.
mvpp2_bm_switch_buffers() is the only place that omits this check.
Add the missing priv->global_tx_fc guard to both the disable and
re-enable calls in mvpp2_bm_switch_buffers(), consistent with the
rest of the driver.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-03
In the Linux kernel, the following vulnerability has been resolved:
udp_tunnel: fix NULL deref caused by udp_sock_create6 when CONFIG_IPV6=n
When CONFIG_IPV6 is disabled, the udp_sock_create6() function returns 0
(success) without actually creating a socket. Callers such as
fou_create() then proceed to dereference the uninitialized socket
pointer, resulting in a NULL pointer dereference.
The captured NULL deref crash:
BUG: kernel NULL pointer dereference, address: 0000000000000018
RIP: 0010:fou_nl_add_doit (net/ipv4/fou_core.c:590 net/ipv4/fou_core.c:764)
[...]
Call Trace:
<TASK>
genl_family_rcv_msg_doit.constprop.0 (net/netlink/genetlink.c:1114)
genl_rcv_msg (net/netlink/genetlink.c:1194 net/netlink/genetlink.c:1209)
[...]
netlink_rcv_skb (net/netlink/af_netlink.c:2550)
genl_rcv (net/netlink/genetlink.c:1219)
netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
netlink_sendmsg (net/netlink/af_netlink.c:1894)
__sock_sendmsg (net/socket.c:727 (discriminator 1) net/socket.c:742 (discriminator 1))
__sys_sendto (./include/linux/file.h:62 (discriminator 1) ./include/linux/file.h:83 (discriminator 1) net/socket.c:2183 (discriminator 1))
__x64_sys_sendto (net/socket.c:2213 (discriminator 1) net/socket.c:2209 (discriminator 1) net/socket.c:2209 (discriminator 1))
do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
entry_SYSCALL_64_after_hwframe (net/arch/x86/entry/entry_64.S:130)
This patch makes udp_sock_create6 return -EPFNOSUPPORT instead, so
callers correctly take their error paths. There is only one caller of
the vulnerable function and only privileged users can trigger it.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-04-03