Linux: >> Linux Kernel >> 5.15.210 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
io_uring/poll: fix signed comparison in io_poll_get_ownership()
io_poll_get_ownership() uses a signed comparison to check whether
poll_refs has reached the threshold for the slowpath:
if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS))
atomic_read() returns int (signed). When IO_POLL_CANCEL_FLAG
(BIT(31)) is set in poll_refs, the value becomes negative in
signed arithmetic, so the >= 128 comparison always evaluates to
false and the slowpath is never taken.
Fix this by casting the atomic_read() result to unsigned int
before the comparison, so that the cancel flag is treated as a
large positive value and correctly triggers the slowpath.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
crypto: jitterentropy - replace long-held spinlock with mutex
jent_kcapi_random() serializes the shared jitterentropy state, but it
currently holds a spinlock across the jent_read_entropy() call. That
path performs expensive jitter collection and SHA3 conditioning, so
parallel readers can trigger stalls as contending waiters spin for
the same lock.
To prevent non-preemptible lock hold, replace rng->jent_lock with a
mutex so contended readers sleep instead of spinning on a shared lock
held across expensive entropy generation.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR
In the SIOCGIFHWADDR path, tap_ioctl() copies 16 bytes of an
uninitialised on-stack struct sockaddr_storage to userspace via
ifr_hwaddr, but netif_get_mac_address() only writes sa_family and
dev->addr_len (6 for Ethernet) bytes, leaving sa_data[6..13] uninitialised.
Those 8 trailing bytes leak kernel stack contents; SIOCGIFHWADDR on a
macvtap chardev returns kernel .text and direct-map pointers, defeating
KASLR.
Initialise ss at declaration.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-24
In the Linux kernel, the following vulnerability has been resolved:
af_unix: Reject SIOCATMARK on non-stream sockets
SIOCATMARK reports whether the receive queue is at the urgent mark for
MSG_OOB.
In AF_UNIX, MSG_OOB is supported only for SOCK_STREAM sockets.
SOCK_DGRAM and SOCK_SEQPACKET reject MSG_OOB in sendmsg() and recvmsg(),
so they should not support SIOCATMARK either.
Return -EOPNOTSUPP for non-stream sockets before checking the receive
queue.
CVSS Score
5.5
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:
net/sched: fix pedit partial COW leading to page cache corruption
tcf_pedit_act() computes the COW range for skb_ensure_writable()
once before the key loop using tcfp_off_max_hint, but the hint does
not account for the runtime header offset added by typed keys. This
can leave part of the write region un-COW'd.
Fix by moving skb_ensure_writable() inside the per-key loop where
the actual write offset is known, and add overflow checking on the
offset arithmetic. For negative offsets (e.g. Ethernet header edits
at ingress), use skb_cow() to COW the headroom instead. Guard
offset_valid() against INT_MIN, where negation is undefined.
CVSS Score
7.8
EPSS Score
0.005
Published
2026-06-16
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: use list_del_rcu for netlink hooks
nft_netdev_unregister_hooks and __nft_unregister_flowtable_net_hooks need
to use list_del_rcu(), this list can be walked by concurrent dumpers.
Add a new helper and use it consistently.
CVSS Score
7.8
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
In the Linux kernel, the following vulnerability has been resolved:
selinux: allow multiple opens of /sys/fs/selinux/policy
Currently there can only be a single open of /sys/fs/selinux/policy at
any time. This allows any process to block any other process from
reading the kernel policy. The original motivation seems to have been
a mix of preventing an inconsistent view of the policy size and
preventing userspace from allocating kernel memory without bound, but
this is arguably equally bad. Eliminate the policy_opened flag and
shrink the critical section that the policy mutex is held. While we
are making changes here, drop a couple of extraneous BUG_ONs.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-06-08
In the Linux kernel, the following vulnerability has been resolved:
lib: test_hmm: evict device pages on file close to avoid use-after-free
Patch series "Minor hmm_test fixes and cleanups".
Two bugfixes a cleanup for the HMM kernel selftests. These were mostly
reported by Zenghui Yu with special thanks to Lorenzo for analysing and
pointing out the problems.
This patch (of 3):
When dmirror_fops_release() is called it frees the dmirror struct but
doesn't migrate device private pages back to system memory first. This
leaves those pages with a dangling zone_device_data pointer to the freed
dmirror.
If a subsequent fault occurs on those pages (eg. during coredump) the
dmirror_devmem_fault() callback dereferences the stale pointer causing a
kernel panic. This was reported [1] when running mm/ksft_hmm.sh on arm64,
where a test failure triggered SIGABRT and the resulting coredump walked
the VMAs faulting in the stale device private pages.
Fix this by calling dmirror_device_evict_chunk() for each devmem chunk in
dmirror_fops_release() to migrate all device private pages back to system
memory before freeing the dmirror struct. The function is moved earlier
in the file to avoid a forward declaration.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-06-08