Linux: >> Linux Kernel >> 5.3.14 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: serialize accept_q access
bt_sock_poll() walks the accept queue without synchronization, while
child teardown can unlink the same socket and drop its last reference.
The unsynchronized accept queue walk has existed since the initial
Bluetooth import.
Protect accept_q with a dedicated lock for queue updates and polling.
Also rework bt_accept_dequeue() to take temporary child references under
the queue lock before dropping it and locking the child socket.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: fix tp_meter counter underflow during shutdown
batadv_tp_sender_shutdown() unconditionally decrements the "sending"
atomic counter. If multiple paths (e.g. timeout, user cancel, and
normal finish) call this function, the counter can underflow to -1.
Since the sender logic treats any non-zero value as "still sending",
a negative value causes the sender kthread to loop indefinitely.
This leads to a use-after-free when the interface is removed while
the zombie thread is still active.
Fix this by using atomic_xchg() to ensure the counter only transitions
from 1 to 0 once.
[sven: added missing change in batadv_tp_send]
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_policy: fix strict mode inbound policy matching
match_policy_in() walks sec_path entries from the last transform to the
first one, but strict policy matching needs to consume info->pol[] in
the same forward order as the rule layout.
Derive the strict-match policy position from the number of transforms
already consumed so that multi-element inbound rules are matched
consistently.
CVSS Score
8.3
EPSS Score
0.003
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_queue: hold bridge skb->dev while queued
br_pass_frame_up() rewrites skb->dev from the ingress port to the bridge
master before queueing bridge LOCAL_IN packets. NFQUEUE only holds
references on state.in/out and bridge physdevs, so a queued bridge
packet can retain a freed bridge master in skb->dev until reinjection.
When the verdict is reinjected later, br_netif_receive_skb() re-enters
the receive path with skb->dev still pointing at the freed bridge master,
triggering a use-after-free.
Store skb->dev in the queue entry, hold a reference on it for the queue
lifetime, and use the saved device when dropping queued packets during
NETDEV_DOWN handling.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: set netns_immutable on the fallback device.
john1988 and Noam Rathaus reported that vti6_init_net() does not set the
netns_immutable flag on the per-netns fallback tunnel device (ip6_vti0).
Other similar tunnel drivers (like ip6_tunnel, sit, ip6_gre, and ip_tunnel)
correctly set this flag during their fallback device initialization to
prevent them from being moved to another network namespace.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-19
In the Linux kernel, the following vulnerability has been resolved:
bpf: Free reuseport cBPF prog after RCU grace period.
Eulgyu Kim reported the splat below with a repro. [0]
The repro sets up a UDP reuseport group with a cBPF prog and
replaces it with a new one while another thread is sending
a UDP packet to the group.
The reuseport prog is freed by sk_reuseport_prog_free().
bpf_prog_put() is called for "e"BPF prog to destruct through
multiple stages while cBPF prog is freed immediately by
bpf_release_orig_filter() and bpf_prog_free().
If a reuseport prog is detached from the setsockopt() path
(reuseport_attach_prog() or reuseport_detach_prog()),
sk_reuseport_prog_free() is called without waiting for RCU
readers to complete, resulting in various bugs.
Let's defer freeing the reuseport cBPF prog after one RCU
grace period.
Note "e"BPF prog is safe as is unless the fast path starts
to touch fields destroyed in bpf_prog_put_deferred() and
__bpf_prog_put_noref().
[0]:
BUG: KASAN: vmalloc-out-of-bounds in reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
Read of size 4 at addr ffffc9000051e004 by task slowme/10208
CPU: 6 UID: 1000 PID: 10208 Comm: slowme Not tainted 7.0.0-geb7ac95ff75e #32 PREEMPT(full)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
udp4_lib_lookup2+0x3bc/0x950 net/ipv4/udp.c:495
__udp4_lib_lookup+0x768/0xe20 net/ipv4/udp.c:723
__udp4_lib_lookup_skb+0x297/0x390 net/ipv4/udp.c:752
__udp4_lib_rcv+0x1312/0x2620 net/ipv4/udp.c:2752
ip_protocol_deliver_rcu+0x282/0x440 net/ipv4/ip_input.c:207
ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6181 [inline]
__netif_receive_skb net/core/dev.c:6294 [inline]
process_backlog+0xaa4/0x1960 net/core/dev.c:6645
__napi_poll+0xae/0x340 net/core/dev.c:7709
napi_poll net/core/dev.c:7772 [inline]
net_rx_action+0x5d7/0xf50 net/core/dev.c:7929
handle_softirqs+0x22b/0x870 kernel/softirq.c:622
do_softirq+0x76/0xd0 kernel/softirq.c:523
</IRQ>
<TASK>
__local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x1dd7/0x3710 net/core/dev.c:4890
neigh_output include/net/neighbour.h:556 [inline]
ip_finish_output2+0xca9/0x1070 net/ipv4/ip_output.c:237
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:438
ip_send_skb+0x45/0xc0 net/ipv4/ip_output.c:1508
udp_send_skb+0xb04/0x1510 net/ipv4/udp.c:1195
udp_sendmsg+0x1a71/0x2350 net/ipv4/udp.c:1485
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x554/0x680 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x160/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x415a2d
Code: b3 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6bc31e41e8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f6bc31e4cdc RCX: 0000000000415a2d
RDX: 0000000000000001 RSI: 00007f6bc31e421f RDI: 0000000000000003
RBP: 00007f6bc31e4240 R08: 00007f6bc31e4220 R09: 0000000000000010
R10: 0000000000000000 R11:
---truncated---
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-19
In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix rlimit for posix cpu timers
Posix cpu timers requires an additional step beyond setting the rlimit.
Refactor the code so its clear when what code is setting the
limit and conditionally update the posix cpu timers when appropriate.
CVSS Score
7.3
EPSS Score
0.001
Published
2026-06-09
In the Linux kernel, the following vulnerability has been resolved:
tap: free page on error paths in tap_get_user_xdp()
tap_get_user_xdp() rejects a frame shorter than ETH_HLEN with -EINVAL,
and returns -ENOMEM when build_skb() fails. Both paths jump to the err
label without freeing the page that vhost_net_build_xdp() allocated for
the frame. tap_sendmsg() discards the per-buffer return value and always
returns 0, so vhost_tx_batch() takes the success path and never frees
the page; each rejected frame in a batch leaks one page-frag chunk.
Free the page on both error paths, before the skb is built. This is the
tap counterpart of the same leak in tun_xdp_one().
CVSS Score
7.4
EPSS Score
0.002
Published
2026-06-09
In the Linux kernel, the following vulnerability has been resolved:
tun: free page on build_skb failure in tun_xdp_one()
When build_skb() fails in tun_xdp_one(), the function sets ret to
-ENOMEM and jumps to the out label, which returns without freeing the
page that vhost_net_build_xdp() allocated for the frame. As with the
short-frame rejection path, tun_sendmsg() discards the per-buffer error
and still returns total_len, so vhost_tx_batch() takes the success path
and never frees the page. Each build_skb() failure in a batch leaks one
page-frag chunk.
Free the page before taking the error path, matching the put_page() the
other error exits of tun_xdp_one() already perform.
CVSS Score
7.1
EPSS Score
0.001
Published
2026-06-09
In the Linux kernel, the following vulnerability has been resolved:
media: videobuf2: Set vma_flags in vb2_dma_sg_mmap
vb2_dma_contig sets VMA flags VM_DONTEXPAND and VM_DONTDUMP and I do not
see a reason why vb2_dma_sg should behave differently. This avoids
hitting `WARN_ON(!(vma->vm_flags & VM_DONTEXPAND));` in
drm_gem_mmap_obj() during mmap() of an imported dma-buf from the out of
tree Apple ISP camera capture driver which uses vb2_dma_sg_memops.
gst-launch-1.0 v4l2src ! gtk4paintablesink
[ 38.201528] ------------[ cut here ]------------
[ 38.202135] WARNING: CPU: 7 PID: 2362 at drivers/gpu/drm/drm_gem.c:1144 drm_gem_mmap_obj+0x1f8/0x210
[ 38.203278] Modules linked in: rfcomm snd_seq_dummy snd_hrtimer
snd_seq snd_seq_device uinput nf_conntrack_netbios_ns
nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib
nft_reject_inet nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat
nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables qrtr bnep
nls_ascii i2c_dev loop fuse dm_multipath nfnetlink brcmfmac_wcc
hid_magicmouse hci_bcm4377 brcmfmac brcmutil bluetooth ecdh_generic
cfg80211 ecc btrfs xor xor_neon rfkill hid_apple raid6_pq joydev
aop_als apple_nvmem_spmi industrialio snd_soc_aop apple_z2
snd_soc_cs42l84 tps6598x snd_soc_tas2764 macsmc_reboot spi_nor
macsmc_hwmon rtc_macsmc gpio_macsmc macsmc_power regmap_spmi
macsmc_input dockchannel_hid panel_summit appledrm nvme_apple dwc3
snd_soc_macaudio drm_client_lib nvme_core phy_apple_atc hwmon
apple_sart apple_dockchannel macsmc apple_rtkit_helper
spmi_apple_controller aop apple_wdt mfd_core nvmem_apple_efuses
pinctrl_apple_gpio apple_isp apple_dcp videobuf2_dma_sg mux_core
spi_apple
[ 38.203300] videobuf2_memops i2c_pasemi_platform snd_soc_apple_mca videobuf2_v4l2 videodev clk_apple_nco videobuf2_common snd_pcm_dmaengine adpdrm asahi apple_admac adpdrm_mipi drm_dma_helper pwm_apple i2c_pasemi_core drm_display_helper mc cec apple_dart ofpart apple_soc_cpufreq leds_pwm phram
[ 38.217677] CPU: 7 UID: 1000 PID: 2362 Comm: gst-launch-1.0 Tainted: G W 6.17.6+ #asahi-dev PREEMPT(full)
[ 38.219040] Tainted: [W]=WARN
[ 38.219398] Hardware name: Apple MacBook Pro (13-inch, M2, 2022) (DT)
[ 38.220213] pstate: 21400005 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[ 38.221088] pc : drm_gem_mmap_obj+0x1f8/0x210
[ 38.221643] lr : drm_gem_mmap_obj+0x78/0x210
[ 38.222178] sp : ffffc0008dc678e0
[ 38.222579] x29: ffffc0008dc678e0 x28: 0000000000042a97 x27: ffff8000b701b480
[ 38.223465] x26: 00000000000000fb x25: ffffc0008dc67d20 x24: ffffc0008dc67968
[ 38.224402] x23: ffff8000e3ca5600 x22: ffff8000265b7800 x21: ffff80003000c0c0
[ 38.225279] x20: 0000000000000000 x19: ffff8000b68c5200 x18: ffffc0008dc67968
[ 38.226151] x17: 0000000000000000 x16: 0000000000000000 x15: ffffc000810a30a8
[ 38.227042] x14: 00007fff637effff x13: 00005555de91ffff x12: 00007fff63293fff
[ 38.227942] x11: 0000000000000000 x10: ffff8000184ecf08 x9 : ffffc0007a1900c8
[ 38.228824] x8 : ffffc0008dc67968 x7 : 0000000000000012 x6 : ffffc0015cf1c000
[ 38.229703] x5 : ffffc0008dc676a0 x4 : ffffc00081a27dc0 x3 : 0000000000000038
[ 38.230607] x2 : 0000000000000003 x1 : 0000000000000003 x0 : 00000000100000fb
[ 38.231488] Call trace:
[ 38.231806] drm_gem_mmap_obj+0x1f8/0x210 (P)
[ 38.232342] drm_gem_mmap+0x140/0x260
[ 38.232813] __mmap_region+0x488/0x9a0
[ 38.233277] mmap_region+0xd0/0x148
[ 38.233703] do_mmap+0x350/0x5c0
[ 38.234148] vm_mmap_pgoff+0x14c/0x200
[ 38.234612] ksys_mmap_pgoff+0x150/0x208
[ 38.235107] __arm64_sys_mmap+0x34/0x50
[ 38.235611] invoke_syscall+0x50/0x120
[ 38.236075] el0_svc_common.constprop.0+0x48/0xf0
[ 38.236680] do_el0_svc+0x24/0x38
[ 38.237113] el0_svc+0x38/0x168
[ 38.237507] el0t_64_sync_handler+0xa0/0xe8
[ 38.238034] el0t_64_sync+0x198/0x1a0
[ 38.238491] ---[ end trace 0000000000000000 ]---
There were discussions in [1] at the end of 2023 that mmap() on imported
---truncated---
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-08