Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
hfsplus: fix uninit-value by validating catalog record size
Syzbot reported a KMSAN uninit-value issue in hfsplus_strcasecmp(). The
root cause is that hfs_brec_read() doesn't validate that the on-disk
record size matches the expected size for the record type being read.
When mounting a corrupted filesystem, hfs_brec_read() may read less data
than expected. For example, when reading a catalog thread record, the
debug output showed:
HFSPLUS_BREC_READ: rec_len=520, fd->entrylength=26
HFSPLUS_BREC_READ: WARNING - entrylength (26) < rec_len (520) - PARTIAL READ!
hfs_brec_read() only validates that entrylength is not greater than the
buffer size, but doesn't check if it's less than expected. It successfully
reads 26 bytes into a 520-byte structure and returns success, leaving 494
bytes uninitialized.
This uninitialized data in tmp.thread.nodeName then gets copied by
hfsplus_cat_build_key_uni() and used by hfsplus_strcasecmp(), triggering
the KMSAN warning when the uninitialized bytes are used as array indices
in case_fold().
Fix by introducing hfsplus_brec_read_cat() wrapper that:
1. Calls hfs_brec_read() to read the data
2. Validates the record size based on the type field:
- Fixed size for folder and file records
- Variable size for thread records (depends on string length)
3. Returns -EIO if size doesn't match expected
For thread records, check against HFSPLUS_MIN_THREAD_SZ before reading
nodeName.length to avoid reading uninitialized data at call sites that
don't zero-initialize the entry structure.
Also initialize the tmp variable in hfsplus_find_cat() as defensive
programming to ensure no uninitialized data even if validation is
bypassed.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: free sk if last
When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer(),
and released at the end.
If at that moment, it was the last reference being held, the sk would
not be freed. sock_put() should then be called instead of __sock_put().
But that's not enough: if it is the last reference, sock_put() will call
sk_free(), which will end up calling sk_stop_timer_sync() on the same
timer, and waiting indefinitely to finish. So it is needed to mark that
the timer is done at the end of the timer handler when it has not been
rescheduled, not to call sk_stop_timer_sync() on "itself".
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
riscv: kvm: fix vector context allocation leak
When the second kzalloc (host_context.vector.datap) fails in
kvm_riscv_vcpu_alloc_vector_context, the first allocation
(guest_context.vector.datap) is leaked. Free it before returning.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
ipv6: xfrm6: release dst on error in xfrm6_rcv_encap()
xfrm6_rcv_encap() performs an IPv6 route lookup when the skb does not
already have a dst attached. ip6_route_input_lookup() returns a
referenced dst entry even when the lookup resolves to an error route.
If dst->error is set, xfrm6_rcv_encap() drops the skb without attaching
the dst to the skb and without releasing the reference returned by the
lookup. Repeated packets hitting this path therefore leak dst entries.
Release the dst before jumping to the drop path.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
exit: prevent preemption of oopsing TASK_DEAD task
When an already-exiting task oopses, make_task_dead() currently calls
do_task_dead() with preemption enabled. That is forbidden:
do_task_dead() calls __schedule(), which has a comment saying "WARNING:
must be called with preemption disabled!".
If an oopsing task is preempted in do_task_dead(), between becoming
TASK_DEAD and entering the scheduler explicitly, bad things happen:
finish_task_switch() assumes that once the scheduler has switched away
from a TASK_DEAD task, the task can never run again and its stack is no
longer needed; but that assumption apparently doesn't hold if the dead
task was preempted (the SM_PREEMPT case).
This means that the scheduler ends up repeatedly dropping references on
the dead task's stack, which can lead to use-after-free or double-free
of the entire task stack; in other words, two tasks can end up running
on the same stack, resulting in various kinds of memory corruption.
(This does not just affect "recursively oopsing" tasks; it is enough to
oops once during task exit, for example in a file_operations::release
handler)
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Read scx_root under scx_cgroup_ops_rwsem in cgroup setters
scx_group_set_{weight,idle,bandwidth}() cache scx_root before acquiring
scx_cgroup_ops_rwsem, so the pointer can be stale by the time the op runs.
If the loaded scheduler is disabled and freed (via RCU work) and another is
enabled between the naked load and the rwsem acquire, the reader sees
scx_cgroup_enabled=true (the new scheduler's) but dereferences the freed one
- UAF on SCX_HAS_OP(sch, ...) / SCX_CALL_OP(sch, ...).
scx_cgroup_enabled is toggled only under scx_cgroup_ops_rwsem write
(scx_cgroup_{init,exit}), so reading scx_root inside the rwsem read section
correlates @sch with the enabled snapshot.
CVSS Score
7.0
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
smb/client: fix out-of-bounds read in smb2_compound_op()
If a server sends a truncated response but a large OutputBufferLength, and
terminates the EA list early, check_wsl_eas() returns success without
validating that the entire OutputBufferLength fits within iov_len.
Then smb2_compound_op() does:
memcpy(idata->wsl.eas, data[0], size[0]);
Where size[0] is OutputBufferLength. If iov_len is smaller than size[0],
memcpy can read beyond the end of the rsp_iov allocation and leak adjacent
kernel heap memory.
CVSS Score
9.1
EPSS Score
0.001
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Fix potential ADE in loongson_gpu_fixup_dma_hang()
The switch case in loongson_gpu_fixup_dma_hang() may not DC2 or DC3, and
readl(crtc_reg) will access with random address, because the "device" is
from "base+PCI_DEVICE_ID", "base" is from "pdev->devfn+1". This is wrong
when my platform inserts a discrete GPU:
lspci -tv
-[0000:00]-+-00.0 Loongson Technology LLC Hyper Transport Bridge Controller
...
+-06.0 Loongson Technology LLC LG100 GPU
+-06.2 Loongson Technology LLC Device 7a37
...
Add a default switch case to fix the panic as below:
Kernel ade access[#1]:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.6.136-loong64-desktop-hwe+ #4
pc 90000000017e5534 ra 90000000017e54c0 tp 90000001002f8000 sp 90000001002fb6c0
a0 80000efe00003100 a1 0000000000003100 a2 0000000000000000 a3 0000000000000002
a4 90000001002fb6b4 a5 900000087cdb58fd a6 90000000027af000 a7 0000000000000001
t0 00000000000085b9 t1 000000000000ffff t2 0000000000000000 t3 0000000000000000
t4 fffffffffffffffd t5 00000000fffb6d9c t6 0000000000083b00 t7 00000000000070c0
t8 900000087cdb4d94 u0 900000087cdb58fd s9 90000001002fb826 s0 90000000031c12c8
s1 7fffffffffffff00 s2 90000000031c12d0 s3 0000000000002710 s4 0000000000000000
s5 0000000000000000 s6 9000000100053000 s7 7fffffffffffff00 s8 90000000030d4000
ra: 90000000017e54c0 loongson_gpu_fixup_dma_hang+0x40/0x210
ERA: 90000000017e5534 loongson_gpu_fixup_dma_hang+0xb4/0x210
CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
PRMD: 00000004 (PPLV0 +PIE -PWE)
EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)
ESTAT: 00480000 [ADEM] (IS= ECode=8 EsubCode=1)
BADV: 7fffffffffffff00
PRID: 0014d000 (Loongson-64bit, Loongson-3A6000-HV)
Modules linked in:
Process swapper/0 (pid: 1, threadinfo=(____ptrval____), task=(____ptrval____))
Stack : 0000000000000006 90000001002fb778 90000001002fb704 0000000000000007
0000000016a65700 90000000017e5690 000000000000ffff ffffffffffffffff
900000000209f7c0 9000000100053000 900000000209f7a8 9000000000eebc08
0000000000000000 0000000000000000 0000000000000006 90000001002fb778
90000001000530b8 90000000027af000 0000000000000000 9000000100054000
9000000100053000 9000000000ebb70c 9000000100004c00 9000000004000001
90000001002fb7e4 bae765461f31cb12 0000000000000000 0000000000000000
0000000000000006 90000000027af000 0000000000000030 90000000027af000
900000087cd6f800 9000000100053000 0000000000000000 9000000000ebc560
7a2500147cdaf720 bae765461f31cb12 0000000000000001 0000000000000030
...
Call Trace:
[<90000000017e5534>] loongson_gpu_fixup_dma_hang+0xb4/0x210
[<9000000000eebc08>] pci_fixup_device+0x108/0x280
[<9000000000ebb70c>] pci_setup_device+0x24c/0x690
[<9000000000ebc560>] pci_scan_single_device+0xe0/0x140
[<9000000000ebc684>] pci_scan_slot+0xc4/0x280
[<9000000000ebdd00>] pci_scan_child_bus_extend+0x60/0x3f0
[<9000000000f5bc94>] acpi_pci_root_create+0x2b4/0x420
[<90000000017e5e74>] pci_acpi_scan_root+0x2d4/0x440
[<9000000000f5b02c>] acpi_pci_root_add+0x21c/0x3a0
[<9000000000f4ee54>] acpi_bus_attach+0x1a4/0x3c0
[<90000000010e200c>] device_for_each_child+0x6c/0xe0
[<9000000000f4bbf4>] acpi_dev_for_each_child+0x44/0x70
[<9000000000f4ef40>] acpi_bus_attach+0x290/0x3c0
[<90000000010e200c>] device_for_each_child+0x6c/0xe0
[<9000000000f4bbf4>] acpi_dev_for_each_child+0x44/0x70
[<9000000000f4ef40>] acpi_bus_attach+0x290/0x3c0
[<9000000000f5211c>] acpi_bus_scan+0x6c/0x280
[<900000000189c028>] acpi_scan_init+0x194/0x310
[<900000000189bc6c>] acpi_init+0xcc/0x140
[<9000000000220cdc>] do_one_initcall+0x4c/0x310
[<90000000018618fc>] kernel_init_freeable+0x258/0x2d4
[<900000000184326c>] kernel_init+0x28/0x13c
[<9000000000222008>] ret_from_kernel_thread+0xc/0xa4
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: oss: Fix data race at accessing runtime.oss.trigger
Currently the runtime.oss.trigger field may be accessed concurrently
without protection, which may lead to the data race. And, in this
case, it may lead to more severe problem because it's a bit field; as
writing the data, it may overwrite other bit fields as well, which
confuses the operation completely, as spotted by fuzzing.
Fix it by covering runtime.oss.trigger bit fled also with the existing
params_lock mutex in both snd_pcm_oss_get_trigger() and
snd_pcm_oss_poll().
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: always decrease sk refcount
When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer().
It should then be released in all cases at the end.
Some (unlikely) checks were returning directly instead of calling
sock_put() to decrease the refcount. Jump to a new 'exit' label to call
__sock_put() (which will become sock_put() in the next commit) to fix
this potential leak.
While at it, drop the '!msk' check which cannot happen because it is
never reset, and explicitly mark the remaining one as "unlikely".
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28