| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: guest_memfd: Treat memslot binding offset+size as unsigned values
When binding a memslot to a guest_memfd file, treat the offset and size as
unsigned values to fix a bug where the sum of the two can result in a false
negative when checking for overflow against the size of the file. Passing
unsigned values also avoids relying on somewhat obscure checks in other
flows for safety, and tracks the offset and size as they are intended to be
tracked, as unsigned values.
On 64-bit kernels, the number of pages a memslot contains and thus the size
(and offset) of its guest_memfd binding are unsigned 64-bit values. Taking
the offset+size as an loff_t instead of a uoff_t inadvertently converts
the unsigned value to a signed value if the offset and/or size is massive.
Locally storing the offset and size as signed values is benign in and of
itself (though even that is *extremely* difficult to discern), but
operating on their sum is not.
For the offset, KVM explicitly checks against a negative value, which might
seem like a bug as KVM could incorrectly reject a legitimate binding, but
that's not actually the case as KVM_CREATE_GUEST_MEMFD takes a signed value
for its size, i.e. a would-be-negative offset is also greater than the
maximum possible size of any guest_memfd file.
Regarding the size, while KVM lacks an explicit check for a negative value,
i.e. seemingly has a flawed overflow check, KVM restricts the number of
pages in a single memslot to the largest positive signed 32-bit value:
if (id < KVM_USER_MEM_SLOTS &&
(mem->memory_size >> PAGE_SHIFT) > KVM_MEM_MAX_NR_PAGES)
return -EINVAL;
and so that maximum "size" will ever be is 0x7fffffff000.
The sum of the two is, however, problematic. While the size is restricted
by KVM's memslot logic, the offset is not, i.e. the offset is completely
unchecked until the "offset + size > i_size_read(inode)" check. If the
offset is the (nearly) largest possible _positive_ value, then adding size
to the offset can result in a signed, negative 64-bit value. When compared
against the size of the file (guaranteed to be positive), the negative sum
is always smaller, and KVM incorrectly allows the absurd offset.
Opportunistically add missing includes in kvm_mm.h (instead of relying on
its parents). |
| In the Linux kernel, the following vulnerability has been resolved:
xfs: don't wrap around quota ids in dqiterate
LOLLM noticed that q_id is an unsigned 32-bit variable. If it happens
to be set to XFS_DQ_ID_MAX due to a filesystem that actually has a dquot
for ID_MAX, then this addition will truncate to zero and the iteration
starts over. Fix this by casting to u64. |
| In the Linux kernel, the following vulnerability has been resolved:
net: garp: fix unsigned integer underflow in garp_pdu_parse_attr
The receive-side GARP attribute parser computes dlen with reversed
operands:
dlen = sizeof(*ga) - ga->len;
ga->len is the on-wire attribute length and includes the GARP attribute
header. For normal attributes with data, ga->len is larger than
sizeof(*ga), so the subtraction underflows in unsigned arithmetic.
The resulting value is later passed to garp_attr_lookup(), whose length
argument is u8. After truncation, the parsed data length usually no
longer matches the length stored for locally registered attributes, so
received Join/Leave events are ignored. This breaks the GARP receive path
for common attributes, such as GVRP VLAN registration attributes.
Compute the data length as the attribute length minus the header length. |
| In the Linux kernel, the following vulnerability has been resolved:
tty: hvc_iucv: fix off-by-one in number of supported devices
MAX_HVC_IUCV_LINES == HVC_ALLOC_TTY_ADAPTERS == 8.
This is the number of entries in:
static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES];
Sometimes hvc_iucv_table[] is limited by:
(a) if (num > hvc_iucv_devices) // for error detection
or
(b) for (i = 0; i < hvc_iucv_devices; i++) // in 2 places
(so these 2 don't agree; second one appears to be correct to me.)
hvc_iucv_devices can be 0..8. This is a counter.
(c) if (hvc_iucv_devices > MAX_HVC_IUCV_LINES)
If hvc_iucv_devices == 8, (a) allows the code to access hvc_iucv_table[8].
Oops. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/amd: Bounds-check devid in __rlookup_amd_iommu()
iommu_device_register() walks every device on the PCI bus via
bus_for_each_dev() and calls amd_iommu_probe_device() for each. The
inlined check_device() path computes the device's sbdf, calls
rlookup_amd_iommu() to find the owning IOMMU, and only afterwards
verifies devid <= pci_seg->last_bdf. __rlookup_amd_iommu() indexes
rlookup_table[devid] with no bounds check of its own, so for a PCI
device whose BDF is not described by the IVRS, the lookup reads past
the end of the allocation before the caller's bounds check can run.
This was harmless before commit e874c666b15b ("iommu/amd: Change
rlookup, irq_lookup, and alias to use kvalloc()"): the table was a
zeroed page-order allocation, so the over-read returned NULL and the
caller's NULL check skipped the device. After that commit the table is
a tight kvcalloc() and the over-read returns adjacent slab contents,
which check_device() then dereferences as a struct amd_iommu *,
causing a boot-time GPF.
Seen on Google Compute Engine ct6e VMs, where the virtualized IVRS
describes only the four TPU endpoints 00:04.0-07.0; the gVNIC at
00:08.0 (devid 0x40) indexes 56 bytes past the 456-byte allocation,
into the adjacent kmalloc-512 slab object:
pci 0000:00:04.0: Adding to iommu group 0
pci 0000:00:05.0: Adding to iommu group 1
pci 0000:00:06.0: Adding to iommu group 2
pci 0000:00:07.0: Adding to iommu group 3
Oops: general protection fault, probably for non-canonical address 0x3a64695f78746382: 0000 [#1] SMP NOPTI
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.18.22 #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/06/2025
RIP: 0010:amd_iommu_probe_device+0x54/0x3a0
Call Trace:
__iommu_probe_device+0x107/0x520
probe_iommu_group+0x29/0x50
bus_for_each_dev+0x7e/0xe0
iommu_device_register+0xc9/0x240
iommu_go_to_state+0x9c0/0x1c60
amd_iommu_init+0x14/0x40
pci_iommu_init+0x16/0x60
do_one_initcall+0x47/0x2f0
Guard the array access in __rlookup_amd_iommu(). With the fix applied
on 6.18.22, the gVNIC at 00:08.0 is skipped cleanly and the VM boots. |
| In the Linux kernel, the following vulnerability has been resolved:
6lowpan: fix off-by-one in multicast context address compression
The second memcpy in lowpan_iphc_mcast_ctx_addr_compress() uses
&data[1] as destination and &ipaddr->s6_addr[11] as source, but
both should be offset by one: &data[2] and &ipaddr->s6_addr[12]
respectively.
This off-by-one has two consequences:
1. data[1] is overwritten with s6_addr[11], corrupting the RIID
field in the compressed multicast address
2. data[5] is never written, so uninitialized kernel stack memory
is transmitted over the network via lowpan_push_hc_data(),
leaking kernel stack contents
The correct inline data layout must match what the decompression
function lowpan_uncompress_multicast_ctx_daddr() expects:
data[0..1] = s6_addr[1..2] (flags/scope + RIID)
data[2..5] = s6_addr[12..15] (group ID)
Also zero-initialize the data array as a defensive measure against
similar bugs in the future. |
| In the Linux kernel, the following vulnerability has been resolved:
thunderbolt: Reject zero-length property entries in validator
tb_property_entry_valid() accepts entries with length == 0 for
DIRECTORY, DATA, and TEXT types. A zero-length TEXT entry passes
validation but causes an underflow in the null-termination logic:
property->value.text[property->length * 4 - 1] = '\0';
When property->length is 0 this writes to offset -1 relative to
the allocation.
Reject zero-length entries early in the validator since they have no
valid representation in the XDomain property protocol. |
| In the Linux kernel, the following vulnerability has been resolved:
dm log: fix out-of-bounds write due to region_count overflow
The local variable region_count in create_log_context() is declared as
unsigned int (32-bit), but dm_sector_div_up() returns sector_t (64-bit).
When a device-mapper target has a sufficiently large ti->len with a small
region_size, the division result can exceed UINT_MAX. The truncated
value is then used to calculate bitset_size, causing clean_bits,
sync_bits, and recovering_bits to be allocated far smaller than needed
for the actual number of regions.
Subsequent log operations (log_set_bit, log_clear_bit, log_test_bit) use
region indices derived from the full untruncated region space, causing
out-of-bounds writes to kernel heap memory allocated by vmalloc.
This can be reproduced by creating a mirror target whose region_count
overflows 32 bits:
dmsetup create bigzero --table '0 8589934594 zero'
dmsetup create mymirror --table '0 8589934594 mirror \
core 2 2 nosync 2 /dev/mapper/bigzero 0 \
/dev/mapper/bigzero 0'
The status output confirms the truncation (sync_count=1 instead of
4294967297, because 0x100000001 was truncated to 1):
$ dmsetup status mymirror
0 8589934594 mirror 2 254:1 254:1 1/4294967297 ...
This leads to a kernel crash in core_in_sync:
BUG: scheduling while atomic: (udev-worker)/9150/0x00000000
RIP: 0010:core_in_sync+0x14/0x30 [dm_log]
CR2: 0000000000000008
Fixing recursive fault but reboot is needed!
Fix by widening the local region_count to sector_t and adding an
explicit overflow check before the value is assigned to lc->region_count. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: target: core: Fix integer overflow in UNMAP bounds check
sbc_execute_unmap() checks LBA + range does not exceed the device capacity,
but does not guard against LBA + range wrapping around on 64-bit overflow.
Add an overflow check matching the pattern already used for WRITE_SAME in
the same file. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: af_alg - Cap AEAD AD length to 0x80000000
In order to prevent arithmetic overflows when checking the TX
buffer size, cap the associated data length to 0x80000000. |
| In the Linux kernel, the following vulnerability has been resolved:
i2c: dev: prevent integer overflow in I2C_TIMEOUT ioctl
While fuzzing with Syzkaller, a persistent `schedule_timeout: wrong
timeout value` warning was observed, accompanied by SMBus controller
state machine corruption.
The I2C_TIMEOUT ioctl accepts a user-provided timeout in multiples of
10 ms. The user argument is checked against INT_MAX, but it is
subsequently multiplied by 10 before being passed to msecs_to_jiffies().
A malicious user can pass a large value (e.g., 429496729) that passes
the `arg > INT_MAX` check but overflows when multiplied by 10. This
results in a truncated 32-bit unsigned value that bypasses the
internal `(int)m < 0` check in `msecs_to_jiffies()`.
The truncated value is then assigned to `client->adapter->timeout`
(a signed 32-bit int), which is reinterpreted as a negative number.
When passed to wait_for_completion_timeout(), this negative value
undergoes sign extension to a 64-bit unsigned long, triggering the
`schedule_timeout` warning and causing premature returns. This leaves
the SMBus state machine in an unrecoverable state, constituting a
local Denial of Service (DoS).
Fix this by bounding the user argument to `INT_MAX / 10`.
[wsa: move the comment as well] |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: stop hash:* range iteration at end
The following hash set variants:
hash:ip,mark
hash:ip,port
hash:ip,port,ip
hash:ip,port,net
iterate IPv4 ranges with a 32-bit iterator.
The iterator must stop once the last address in the requested range has
been processed. Advancing it once more can move the traversal state past
the end of the request, so a later retry may continue from an unintended
position.
Handle the iterator increment explicitly at the end of the loop and stop
once the upper bound has been processed. This keeps the existing retry
behaviour intact for valid ranges while preventing traversal from
continuing past the original boundary. |
| In the Linux kernel, the following vulnerability has been resolved:
dm: fix a buffer overflow in ioctl processing
Tony Asleson (using Claude) found a buffer overflow in dm-ioctl in the
function retrieve_status:
1. The code in retrieve_status checks that the output string fits into
the output buffer and writes the output string there
2. Then, the code aligns the "outptr" variable to the next 8-byte
boundary:
outptr = align_ptr(outptr);
3. The alignment doesn't check overflow, so outptr could point past the
buffer end
4. The "for" loop is iterated again, it executes:
remaining = len - (outptr - outbuf);
5. If "outptr" points past "outbuf + len", the arithmetics wraps around
and the variable "remaining" contains unusually high number
6. With "remaining" being high, the code writes more data past the end of
the buffer
Luckily, this bug has no security implications because:
1. Only root can issue device mapper ioctls
2. The commonly used libraries that communicate with device mapper
(libdevmapper and devicemapper-rs) use buffer size that is aligned to
8 bytes - thus, "outptr = align_ptr(outptr)" can't overshoot the input
buffer and the bug can't happen accidentally |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: fix num_ops off-by-one when crypto allocation fails
move_dirty_folio_in_page_array() may fail if the file is encrypted, the
dirty folio is not the first in the batch, and it fails to allocate a
bounce buffer to hold the ciphertext. When that happens,
ceph_process_folio_batch() simply redirties the folio and flushes the
current batch -- it can retry that folio in a future batch.
However, if this failed folio is not contiguous with the last folio that
did make it into the batch, then ceph_process_folio_batch() has already
incremented `ceph_wbc->num_ops`; because it doesn't follow through and
add the discontiguous folio to the array, ceph_submit_write() -- which
expects that `ceph_wbc->num_ops` accurately reflects the number of
contiguous ranges (and therefore the required number of "write extent"
ops) in the writeback -- will panic the kernel:
BUG_ON(ceph_wbc->op_idx + 1 != req->r_num_ops);
This issue can be reproduced on affected kernels by writing to
fscrypt-enabled CephFS file(s) with a 4KiB-written/4KiB-skipped/repeat
pattern (total filesize should not matter) and gradually increasing the
system's memory pressure until a bounce buffer allocation fails.
Fix this crash by decrementing `ceph_wbc->num_ops` back to the correct
value when move_dirty_folio_in_page_array() fails, but the folio already
started counting a new (i.e. still-empty) extent.
The defect corrected by this patch has existed since 2022 (see first
`Fixes:`), but another bug blocked multi-folio encrypted writeback until
recently (see second `Fixes:`). The second commit made it into 6.18.16,
6.19.6, and 7.0-rc1, unmasking the panic in those versions. This patch
therefore fixes a regression (panic) introduced by cac190c7674f. |
| In the Linux kernel, the following vulnerability has been resolved:
md/raid10: fix deadlock with check operation and nowait requests
When an array check is running it will raise the barrier at which point
normal requests will become blocked and increment the nr_pending value to
signal there is work pending inside of wait_barrier(). NOWAIT requests
do not block and so will return immediately with an error, and additionally
do not increment nr_pending in wait_barrier(). Upstream change commit
43806c3d5b9b ("raid10: cleanup memleak at raid10_make_request") added a
call to raid_end_bio_io() to fix a memory leak when NOWAIT requests hit
this condition. raid_end_bio_io() eventually calls allow_barrier() and
it will unconditionally do an atomic_dec_and_test(&conf->nr_pending) even
though the corresponding increment on nr_pending didn't happen in the
NOWAIT case.
This can be easily seen by starting a check operation while an application
is doing nowait IO on the same array. This results in a deadlocked state
due to nr_pending value underflowing and so the md resync thread gets stuck
waiting for nr_pending to == 0.
Output of r10conf state of the array when we hit this condition:
crash> struct r10conf
barrier = 1,
nr_pending = {
counter = -41
},
nr_waiting = 15,
nr_queued = 0,
Example of md_sync thread stuck waiting on raise_barrier() and other
requests stuck in wait_barrier():
md1_resync
[<0>] raise_barrier+0xce/0x1c0
[<0>] raid10_sync_request+0x1ca/0x1ed0
[<0>] md_do_sync+0x779/0x1110
[<0>] md_thread+0x90/0x160
[<0>] kthread+0xbe/0xf0
[<0>] ret_from_fork+0x34/0x50
[<0>] ret_from_fork_asm+0x1a/0x30
kworker/u1040:2+flush-253:4
[<0>] wait_barrier+0x1de/0x220
[<0>] regular_request_wait+0x30/0x180
[<0>] raid10_make_request+0x261/0x1000
[<0>] md_handle_request+0x13b/0x230
[<0>] __submit_bio+0x107/0x1f0
[<0>] submit_bio_noacct_nocheck+0x16f/0x390
[<0>] ext4_io_submit+0x24/0x40
[<0>] ext4_do_writepages+0x254/0xc80
[<0>] ext4_writepages+0x84/0x120
[<0>] do_writepages+0x7a/0x260
[<0>] __writeback_single_inode+0x3d/0x300
[<0>] writeback_sb_inodes+0x1dd/0x470
[<0>] __writeback_inodes_wb+0x4c/0xe0
[<0>] wb_writeback+0x18b/0x2d0
[<0>] wb_workfn+0x2a1/0x400
[<0>] process_one_work+0x149/0x330
[<0>] worker_thread+0x2d2/0x410
[<0>] kthread+0xbe/0xf0
[<0>] ret_from_fork+0x34/0x50
[<0>] ret_from_fork_asm+0x1a/0x30 |
| In the Linux kernel, the following vulnerability has been resolved:
dm mirror: fix integer overflow in create_dirty_log()
The argument count calculation in create_dirty_log() performs
`*args_used = 2 + param_count` before validating against argc. When a
user provides a param_count close to UINT_MAX via the device mapper
table string, this unsigned addition wraps around to a small value,
causing the subsequent `argc < *args_used` check to be bypassed.
The overflowed param_count is then passed as argc to dm_dirty_log_create(),
where it can cause out-of-bounds reads on the argv array.
Fix by comparing param_count against argc - 2 before performing the
addition, following the same pattern used by parse_features() in the
same file. Since argc >= 2 is already guaranteed, the subtraction is
safe. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Avoid integer underflow in EOP ring size calculation.
The low 6 bits of cp_hqd_eop_control store the base-2 logarithm
of the EOP ring size. This was calculated as
order_base_2(q->eop_ring_buffer_size / 4) - 1
But order_base_2 can in theory return 0, so this could underflow
(although in practice the ring buffer size cannot be less than 4096).
Change this to
order_base_2(q->eop_ring_buffer_size / 8)
using properties of logarithms.
Also add to the above comment to make the mathematics more clear.
(cherry picked from commit f0f43fcf8b2b3a924cad9444340921c96ed5f634) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Avoid integer underflow with ffs in EOP ring size calc
The low 6 bits of cp_hqd_eop_control store the base-2 logarithm
of the EOP ring size. This was calculated as
ffs(q->eop_ring_buffer_size / sizeof(unsigned int)) - 1 - 1
But ffs can in theory return 1 or 0, so this could underflow
(although in practice the ring buffer size cannot be less than 4096).
Change this to
ffs(q->eop_ring_buffer_size / sizeof(unsigned int) / 4)
using properties of logarithms.
(cherry picked from commit 4f18c56630383c14bfc6b2d65f88f2f895d2121a) |
| A flaw was found in GStreamer gst-plugins-good (avidemux). In the superindex and subindex parsers, integer overflow can bypass bounds checks and cause out-of-bounds reads. Because avidemux is auto-plugged by playbin, decodebin, and gst-discoverer, opening or previewing a crafted AVI is sufficient to trigger the issue. Fixed upstream in gst-plugins-good 1.28.6 (GStreamer-SA-2026-0072). |
| musl libc before 1.2.7, when an untrusted regular expression is used with regcomp, has multiple integer overflows, possibly leading to incorrect allocation sizes and out-of-bounds heap writes. |