| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
drm/edid: fix OOB read in drm_parse_tiled_block()
drm_parse_tiled_block() casts the DisplayID block to a
struct displayid_tiled_block and reads the full fixed layout up to
tile->topology_id[7] without checking block->num_bytes. The DisplayID
iterator only validates the declared payload length, so a crafted EDID
can advertise a tiled-display block (tag DATA_BLOCK_TILED_DISPLAY, or
DATA_BLOCK_2_TILED_DISPLAY_TOPOLOGY for v2.0) with a small num_bytes at
the end of a DisplayID extension. The read then runs past the end of the
exact-sized kmemdup()'d EDID allocation, a heap out-of-bounds read.
Reject blocks shorter than the spec's 22-byte tiled payload before
reading the fixed struct, as drm_parse_vesa_mso_data() already does.
BUG: KASAN: slab-out-of-bounds in drm_edid_connector_update
Read of size 2 at addr ffff888010077700 by task exploit/147
dump_stack_lvl (lib/dump_stack.c:94 ...)
print_report (mm/kasan/report.c:378 ...)
kasan_report (mm/kasan/report.c:595)
drm_edid_connector_update (drivers/gpu/drm/drm_edid.c:7581)
bochs_connector_helper_get_modes (drivers/gpu/drm/tiny/bochs.c:574)
drm_helper_probe_single_connector_modes (drivers/gpu/drm/drm_probe_helper.c:426)
status_store (drivers/gpu/drm/drm_sysfs.c:219)
...
vfs_write (fs/read_write.c:595 fs/read_write.c:688)
ksys_write (fs/read_write.c:740) |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet-tcp: Fix potential UAF when ddgst mismatch
Shivam Kumar found via vulnerability testing:
When data digest is enabled on an NVMe/TCP connection and a digest
mismatch occurs on a non-final H2C_DATA PDU during an R2T-based
data transfer, the digest error handler in nvmet_tcp_try_recv_ddgst()
calls nvmet_req_uninit() — which performs percpu_ref_put() on the
submission queue — but does NOT mark the command as completed. It
does not set cqe->status, does not modify rbytes_done, and does not
clear any flag. When the subsequent fatal error triggers queue
teardown, nvmet_tcp_uninit_data_in_cmds() iterates all commands,
checks nvmet_tcp_need_data_in() for each one, and finds that the
already-uninited command still appears to need data (because
rbytes_done < transfer_len and cqe->status == 0). It therefore calls
nvmet_req_uninit() a second time on the same command — a double
percpu_ref_put against a single percpu_ref_get. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation}
In do_action()'s UpdateRecordDataRoot (fslog.c:3489) and
UpdateRecordDataAllocation (fslog.c:3697) cases, the memmove
destination is `Add2Ptr(e, le16_to_cpu(e->view.data_off))`,
where e->view.data_off comes from an on-disk NTFS_DE inside
an INDEX_ROOT or INDEX_BUFFER. Neither case validates
view.data_off + dlen against e->size; the existing
check_if_index_root / check_if_alloc_index helpers walk the
entry chain and validate the entry's offset, but not its
internal view fields.
The neighbouring read sites (e.g., fs/ntfs3/index.c when
iterating view entries) check view.data_off + view.data_size
<= e->size. Apply the same bound at the two memmove sites.
Reproduced under UML+KASAN on mainline 8d90b09e6741 via
pr_warn-only probe instrumentation: with view.data_off forced
to 0xFFFC, the memmove writes 32 bytes past the end of the
NTFS_DE.
This is similar in shape to Pavitra Jha's 2026-05-02 patch
"fs/ntfs3: prevent oob in case UpdateRecordDataRoot"
(<20260502105008.21827-1-jhapavitra98@gmail.com>) which
proposes calling ntfs3_bad_de_range(); that helper does not
exist in mainline. This patch uses inline checks. |
| In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: reject oversized nested action attrs
Open vSwitch stores generated flow actions as nlattrs, whose nla_len
field is u16. Commit a1e64addf3ff ("net: openvswitch: remove
misbehaving actions length check") allowed the total sw_flow_actions
stream to grow beyond 64 KiB, which is valid, but also removed the last
guard preventing a generated nested action attribute from exceeding
U16_MAX.
An oversized generated container can thus be closed with a truncated
nla_len. A later dump or teardown then walks a structurally different
stream than the one that was validated. In particular, an oversized
nested CLONE/CT action may cause subsequent bytes in the generated
stream to be interpreted as independent actions.
Keep the larger total-action-stream behavior, but make nested action
close reject generated containers that do not fit in nla_len, and return
the error through all callers. For recursive SAMPLE, CLONE, DEC_TTL, and
CHECK_PKT_LEN builders, trim resource-owning action-list tails in reverse
construction order before discarding failed wrappers, so resources copied
into the rejected tails are released before the wrappers are removed.
Most failed outer wrappers are discarded by truncating actions_len after
child resources have been released. CHECK_PKT_LEN also trims its parent
after branch resources are gone. SET/TUNNEL close failures unwind their
known tun_dst ownership directly, and SET_TO_MASKED has no external
ownership and truncates on close failure. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA
mlx5e_xfrm_add_state() handles acquire-flow temporary SAs by allocating
software state and skipping hardware offload setup.
That path jumps to the common success label before taking the eswitch mode
block. After tunnel-mode validation was moved earlier, the common success
label unconditionally calls mlx5_eswitch_unblock_mode(). For acquire SAs,
this decrements esw->offloads.num_block_mode without a matching increment.
Return directly after installing the acquire SA offload handle, so only the
paths that successfully called mlx5_eswitch_block_mode() call the matching
unblock. |
| In the Linux kernel, the following vulnerability has been resolved:
iio: event: Fix event FIFO reset race
`iio_event_getfd()` creates the event file descriptor with
`anon_inode_getfd()`, which allocates a new fd, creates the anonymous
file and installs it in the process fd table before returning to the
caller.
The IIO code resets the event FIFO after `anon_inode_getfd()` has returned,
but before `IIO_GET_EVENT_FD_IOCTL` has copied the fd number to userspace.
But since fd tables are shared between threads, another thread can guess
the newly allocated fd number and issue a `read()` on it as soon as the fd
has been installed.
This means the `kfifo_to_user()` in `iio_event_chrdev_read()` can run in
parallel with the `kfifo_reset_out()` in `iio_event_getfd()`.
The kfifo documentation says that `kfifo_reset_out()` is only safe when it
is called from the reader thread and there is only one concurrent reader.
Otherwise it is dangerous and must be handled in the same way as
`kfifo_reset()`.
If that happens, `kfifo_to_user()` can advance the FIFO `out` index based
on state from before the reset, after the reset has already moved the `out`
index to the current `in` index. That can leave the FIFO with an `out`
index past the `in` index. A later `read()` can then see an underflowed
FIFO length and copy more data than the event FIFO buffer contains. This
can result in an out-of-bounds read and leak adjacent kernel memory to
userspace.
Move the FIFO reset before `anon_inode_getfd()`. At that point the event fd is
marked busy, but the new fd has not been installed yet, so userspace cannot
access it while the FIFO is reset. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: virtio: Validate control metadata from the device
virtio-snd control handling trusts the device-provided control type and
value count returned by the device.
That metadata is then used directly to index g_v2a_type_map[] in
virtsnd_kctl_info(), and to size loops and memcpy() operations in
virtsnd_kctl_get() and virtsnd_kctl_put() against fixed-size
virtio_snd_ctl_value and snd_ctl_elem_value arrays.
A buggy or malicious device can therefore trigger out-of-bounds access by
advertising an invalid control type or an oversized value count.
Validate control type and count once in virtsnd_kctl_parse_cfg(), before
querying enumerated items or exposing the control to ALSA. |
| In the Linux kernel, the following vulnerability has been resolved:
PCI/IOV: Skip VF Resizable BAR restore on read error
sriov_restore_vf_rebar_state() uses the VF Resizable BAR Control register
to decide how many VF BARs to restore (nbars) and which VF BAR each
iteration addresses (bar_idx). bar_idx indexes into dev->sriov->barsz[],
which has only PCI_SRIOV_NUM_BARS (6) entries.
When a device does not respond, config reads typically return
PCI_ERROR_RESPONSE (~0). Both fields are 3 bits wide, so nbars and bar_idx
both evaluate to 7. The barsz[] access then goes out of bounds. UBSAN
reports this as:
UBSAN: array-index-out-of-bounds in drivers/pci/iov.c:948:51 index 7 is out of range for type 'resource_size_t [6]'
Observed on an NVIDIA RTX PRO 1000 GPU (GB207GLM) that stopped responding
during a failed GC6 power state exit. The subsequent pci_restore_state()
invoked sriov_restore_vf_rebar_state() while config reads returned
0xffffffff, triggering the splat.
Bail out if any VF Resizable BAR Control read returns PCI_ERROR_RESPONSE.
No further VF BARs are touched, which is safe because a config read that
returns PCI_ERROR_RESPONSE indicates the device is unreachable and
restoration is pointless. This mirrors the guard in
pci_restore_rebar_state(). |
| In the Linux kernel, the following vulnerability has been resolved:
net: af_key: initialize alg_key_len for IPComp states
pfkey_msg2xfrm_state() handles the IPComp (SADB_X_SATYPE_IPCOMP) case by
allocating x->calg and copying only the algorithm name:
x->calg = kmalloc_obj(*x->calg);
if (!x->calg) {
err = -ENOMEM;
goto out;
}
strcpy(x->calg->alg_name, a->name);
x->props.calgo = sa->sadb_sa_encrypt;
Unlike the authentication (x->aalg) and encryption (x->ealg) branches of
the same function, the compression branch never initializes
calg->alg_key_len. IPComp carries no key and the allocation only
reserves sizeof(struct xfrm_algo) (i.e. no room for a key), so the field
is left containing uninitialized slab data.
calg->alg_key_len is later used as a length by xfrm_algo_clone() when an
IPComp state is cloned during XFRM_MSG_MIGRATE:
xfrm_state_migrate()
xfrm_state_clone_and_setup()
x->calg = xfrm_algo_clone(orig->calg);
kmemdup(orig, xfrm_alg_len(orig));
where xfrm_alg_len() returns sizeof(*alg) + (alg_key_len + 7) / 8. With
a non-zero garbage alg_key_len, kmemdup() reads past the end of the
68-byte calg object. Adding an IPComp SA via PF_KEY and then migrating
it triggers (net-next, KASAN, init_on_alloc=0):
BUG: KASAN: slab-out-of-bounds in kmemdup_noprof+0x44/0x60
Read of size 4164 at addr ff11000025a74980 by task diag2/9287
CPU: 3 UID: 0 PID: 9287 Comm: diag2 7.1.0-rc6-g903db046d557 #1
Call Trace:
<TASK>
dump_stack_lvl+0x10e/0x1f0
print_report+0xf7/0x600
kasan_report+0xe4/0x120
kasan_check_range+0x105/0x1b0
__asan_memcpy+0x23/0x60
kmemdup_noprof+0x44/0x60
xfrm_state_migrate+0x70a/0x1da0
xfrm_migrate+0x753/0x18a0
xfrm_do_migrate+0xb47/0xf10
xfrm_user_rcv_msg+0x411/0xb50
netlink_rcv_skb+0x158/0x420
xfrm_netlink_rcv+0x71/0x90
netlink_unicast+0x584/0x850
netlink_sendmsg+0x8b0/0xdc0
____sys_sendmsg+0x9f7/0xb90
___sys_sendmsg+0x134/0x1d0
__sys_sendmsg+0x16d/0x220
do_syscall_64+0x116/0x7d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
Allocated by task 9287:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
__kasan_kmalloc+0xaa/0xb0
pfkey_add+0x2652/0x2ea0
pfkey_process+0x6d0/0x830
pfkey_sendmsg+0x42c/0x850
__sys_sendto+0x461/0x4b0
__x64_sys_sendto+0xe0/0x1c0
do_syscall_64+0x116/0x7d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ff11000025a74980
which belongs to the cache kmalloc-96 of size 96
The buggy address is located 0 bytes inside of
allocated 68-byte region [ff11000025a74980, ff11000025a749c4)
Depending on the uninitialized value the same field can instead request
an oversized kmemdup() allocation and make the migration clone fail.
The XFRM netlink path is not affected: verify_one_alg() rejects an
XFRMA_ALG_COMP attribute shorter than xfrm_alg_len(), so a calg added via
XFRM_MSG_NEWSA is always self-consistent.
Initialize calg->alg_key_len to 0, matching the aalg/ealg branches. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: validate option length before reading conf opt value
l2cap_get_conf_opt() derives the option length from the
attacker-controlled opt->len field and immediately dereferences
opt->val (as u8, get_unaligned_le16() or get_unaligned_le32(), or a
raw pointer for the default case) before any caller has confirmed
that opt->len bytes are present in the buffer. The callers
(l2cap_parse_conf_req(), l2cap_parse_conf_rsp() and
l2cap_conf_rfc_get()) only detect a malformed option afterwards, once
the running length has gone negative, by which point the
out-of-bounds read has already executed.
An existing post-hoc length check keeps the garbage value from being
consumed, so this is not a data leak in the current control flow. It
is still a validate-after-use ordering bug: up to 4 bytes are read
past the end of the buffer before it is known to contain them, and it
is fragile to future changes in the callers.
Fix it at the source. Pass the end of the buffer into
l2cap_get_conf_opt() and refuse to touch opt->val unless the full
option (header + value) fits. Each caller computes an end pointer
once before the loop and checks the return value directly instead of
inferring the error from a negative length. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: multitouch: fix out-of-bounds bit access on mt_io_flags
mt_io_flags is a single unsigned long, but mt_process_slot(),
mt_release_pending_palms() and mt_release_contacts() use it as a
per-slot bitmap indexed by the slot number. That slot number is only
bounded by td->maxcontacts, which is taken from the device's
ContactCountMaximum feature report and can be up to 255, not by
BITS_PER_LONG.
As a result, a multitouch device that advertises a large contact count
makes set_bit()/clear_bit() operate past the mt_io_flags word and
corrupt the adjacent members of struct mt_device. The sticky-fingers
release timer is the easiest way to reach this. mt_release_contacts()
runs
for (i = 0; i < mt->num_slots; i++)
clear_bit(i, &td->mt_io_flags);
with num_slots == maxcontacts. For maxcontacts around 250 the loop
clears the bits that overlap td->applications.next, zeroing that list
head, and the list_for_each_entry() that immediately follows then
dereferences NULL. The kernel panics from timer (softirq) context. On a
KASAN build this shows up as a general protection fault in
mt_release_contacts() with a null-ptr-deref at offset 0x58, which is
offsetof(struct mt_application, num_received).
The state is reachable from an untrusted USB or Bluetooth HID
multitouch device; no local privileges are required.
Store the per-slot active state in a separately allocated bitmap sized
for maxcontacts, the same pattern already used for pending_palm_slots,
and keep only MT_IO_FLAGS_RUNNING in mt_io_flags. The two
"mt_io_flags & MT_IO_SLOTS_MASK" arming checks become
bitmap_empty(td->active_slots, td->maxcontacts).
Move MT_IO_FLAGS_RUNNING back to bit 0. It was bumped to bit 32 by the
same commit to leave the low byte for the slot bits; with the slot bits
gone it fits in bit 0 again, which also keeps it within the unsigned
long on 32-bit. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject fragmented frames in devmap
Devmap broadcast redirects clone the packet for all but the last
destination.
For native XDP, that clone path copies only the linear xdp_frame data,
while fragmented frames keep skb_shared_info in tailroom outside the
linear area. Cloning such a frame leaves XDP_FLAGS_HAS_FRAGS set but
without valid frag metadata, and the later free path can interpret
uninitialized tail data as skb_shared_info, leading to an out-of-bounds
access during frame return.
Reject fragmented native XDP frames in dev_map_enqueue_clone().
Add the same restriction to the generic XDP clone path in
dev_map_redirect_clone(). Generic XDP represents fragmented packets as
nonlinear skbs, and rejecting them here keeps clone-based broadcast
support aligned between native and generic XDP. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Validate BTF repeated field counts before expansion
btf_parse_struct_metas() walks user-supplied BTF during BPF_BTF_LOAD,
and btf_repeat_fields() expands repeatable fields from array elements
into the fixed BTF_FIELDS_MAX scratch array used by btf_parse_fields().
The remaining-capacity check performs the expanded field count calculation
in u32. A malformed BTF can wrap that calculation, causing the check to
pass even when the expanded field count exceeds the scratch array
capacity. The following memcpy() can then write past the end of the
array.
Use checked addition and multiplication before copying repeated fields
and reject impossible counts. |
| In the Linux kernel, the following vulnerability has been resolved:
udf: validate free block extents against the partition length
udf_free_blocks() checks the logical block number and count against the
partition length, but drops the extent offset from that final bound. A
crafted extent can pass the guard while logicalBlockNum + offset + count
points past the partition, which later indexes past the space bitmap
array.
A single ftruncate(2) on a file backed by such an extent reliably
panics the kernel. This is a local availability issue. On desktop
systems where UDisks/polkit allows the active user to mount removable
UDF media without CAP_SYS_ADMIN, an unprivileged local user can supply
the crafted filesystem and trigger the panic by truncating a writable
file on it. Systems that require root or CAP_SYS_ADMIN to mount the
image have a higher prerequisite.
No confidentiality or integrity impact is claimed: the reproduced
primitive is an out-of-bounds read of a bitmap pointer slot followed by
a kernel panic.
Use the already computed logicalBlockNum + offset + count value for the
partition length check. Also make load_block_bitmap() reject an
out-of-range block group before indexing s_block_bitmap[], so corrupted
callers cannot walk past the flexible array. |
| In the Linux kernel, the following vulnerability has been resolved:
exfat: bound uniname advance in exfat_find_dir_entry()
In exfat_find_dir_entry(), each TYPE_EXTEND (file name) entry advances the
output pointer by a fixed amount while the loop guard only tracks the
accumulated name length:
if (++order == 2)
uniname = p_uniname->name;
else
uniname += EXFAT_FILE_NAME_LEN;
len = exfat_extract_uni_name(ep, entry_uniname);
name_len += len;
unichar = *(uniname+len);
*(uniname+len) = 0x0;
uniname grows by EXFAT_FILE_NAME_LEN (15) per name entry, but name_len
grows only by the actual extracted length, which is shorter when a name
fragment contains an early NUL. The only guard is
`name_len >= MAX_NAME_LENGTH`, so a crafted directory with many short
name fragments lets uniname run far past the
p_uniname->name[MAX_NAME_LENGTH + 3] buffer while name_len stays small,
causing an out-of-bounds read and write at *(uniname+len).
The sibling extractor exfat_get_uniname_from_ext_entry() already stops
on a short fragment (the lockstep `len != EXFAT_FILE_NAME_LEN` guard
added in commit d42334578eba ("exfat: check if filename entries exceeds
max filename length")); exfat_find_dir_entry() never got the
equivalent. Track the per-entry write offset as a count and reject a
fragment once the offset, or the offset plus the extracted length, would
exceed MAX_NAME_LENGTH, before forming the output pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
Input: synaptics-rmi4 - bound the F3A keymap to the GPIO count
rmi_f3a_initialize() takes the GPIO count from the device query register
(f3a->gpio_count = buf & RMI_F3A_GPIO_COUNT, range 0..127).
rmi_f3a_map_gpios() then allocates gpio_key_map with
min(gpio_count, TRACKSTICK_RANGE_END) == at most 6 entries, but
rmi_f3a_attention() iterates the full gpio_count and dereferences
gpio_key_map[i], and input->keycodemax is set to the full gpio_count
while input->keycode points at the 6-entry allocation.
A device that reports gpio_count > 6 therefore causes an out-of-bounds
read of gpio_key_map[] on every attention interrupt, and out-of-bounds
accesses through the input core's default keymap ioctls: EVIOCGKEYCODE
reads past the buffer (leaking adjacent slab memory to user space) and
EVIOCSKEYCODE writes a caller-controlled value past it, for any process
able to open the evdev node, since input_default_getkeycode() and
input_default_setkeycode() only bound the index against keycodemax.
Size the keymap for the full gpio_count. The mapping loop is unchanged:
it still assigns only the first min(gpio_count, TRACKSTICK_RANGE_END)
entries; the remaining slots stay KEY_RESERVED (devm_kcalloc zero-fills)
and are skipped when reporting. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: codecs: simple-mux: Fix enum control bounds check
simple_mux_control_put() rejects values greater than e->items, but
enum control values are zero based. For the two-entry mux used by this
driver, valid values are 0 and 1, so value 2 must be rejected as well.
Accepting e->items can store an invalid mux state, pass it to the GPIO
setter, and pass it on to the DAPM mux update path where it is used as
an index into the enum text array.
Use the same >= e->items check used by the ASoC enum helpers. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Validate payload length and link_index in dc_process_dmub_aux_transfer_async
[Why&How]
dc_process_dmub_aux_transfer_async() copies payload->length bytes into a
16-byte stack buffer (dpaux.data[16]) guarded only by an ASSERT(), which
is a no-op in release builds. If a caller ever passes length > 16 this
results in a stack buffer overflow via memcpy.
Additionally, link_index is used to dereference dc->links[] without
bounds checking against dc->link_count, risking an out-of-bounds access.
Replace the ASSERT with a hard runtime check that returns false when
payload->length exceeds the destination buffer size, and add a bounds
check for link_index before it is used.
(cherry picked from commit ba4caa9fecdf7a38f98c878ad05a8a64148b6881) |
| In the Linux kernel, the following vulnerability has been resolved:
ipv4: raw: reject IP_HDRINCL packets with ihl < 5
raw_send_hdrinc() validates that the caller-supplied IPv4 header
fits within the message length:
iphlen = iph->ihl * 4;
err = -EINVAL;
if (iphlen > length)
goto error_free;
if (iphlen >= sizeof(*iph)) {
/* fix up saddr, tot_len, id, csum, transport_header */
}
It does not, however, reject ihl < 5. For such a packet the
"if (iphlen >= sizeof(*iph))" branch is skipped, leaving the
crafted iphdr untouched, but the packet is still handed to
__ip_local_out() and onward. Downstream consumers that read
iph->ihl assume a sane value: net/ipv4/ah4.c:ah_output() in
particular subtracts sizeof(struct iphdr) from top_iph->ihl * 4
and passes the (signed-int-negative, then cast to size_t)
result to memcpy(), producing an OOB access of length close to
SIZE_MAX and a host kernel panic.
An IPv4 header with ihl < 5 is malformed by definition (RFC 791:
"Internet Header Length is the length of the internet header in
32 bit words ... Note that the minimum value for a correct header
is 5."). The kernel should not be willing to inject such a
packet into its own output path.
Reject "iphlen < sizeof(*iph)" alongside the existing
"iphlen > length" check. This matches the principle that locally
constructed packets that re-enter the IP stack must pass the same
basic sanity tests that a foreign packet would be subjected to.
Once this lands, the "if (iphlen >= sizeof(*iph))" wrapper around
the fixup branch becomes redundant; left in place to keep the
patch minimal and backport-friendly. A follow-up can unwrap it.
Note that commit 86f4c90a1c5c ("ipv4, ipv6: ensure raw socket
message is big enough to hold an IP header") ensures the message
buffer is large enough to hold an iphdr, but does not constrain
the self-reported iph->ihl.
Reachability: the malformed packet source is any caller with
CAP_NET_RAW, including an unprivileged process in a user+net
namespace on a kernel with CONFIG_USER_NS=y. The reproduced AH
crash also requires a matching xfrm AH policy on the outgoing
route; a container granted CAP_NET_ADMIN can install that state
and policy in its netns. Loopback bypasses xfrm_output, so the
trigger uses a real netdev.
Reproduced on UML + KASAN: kernel-mode fault at addr 0x0 with
memcpy_orig at the crash site. Same shape reproduces inside a
rootless Docker container with --cap-add NET_ADMIN on a stock
distro kernel. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/siw: Reject MPA FPDU length underflow before signed receive math
A malicious connected siw peer can send an iWARP FPDU whose MPA length
field (c_hdr->mpa_len, 16 bit big-endian, peer-controlled) is smaller
than the fixed DDP/RDMAP header for the announced opcode. Soft-iWARP
parses the full header in siw_get_hdr() based on iwarp_pktinfo[opcode]
.hdr_len, but never compares mpa_len against that header length.
siw_tcp_rx_data() then derives
srx->fpdu_part_rem = be16_to_cpu(mpa_len) - fpdu_part_rcvd
+ MPA_HDR_SIZE;
where fpdu_part_rcvd equals iwarp_pktinfo[opcode].hdr_len at this
point. For a tagged WRITE (hdr_len 16, MPA_HDR_SIZE 2) the smallest
on-wire mpa_len of 0 yields fpdu_part_rem = -14, and any mpa_len below
hdr_len - MPA_HDR_SIZE underflows to a negative int.
The signed value then flows into siw_proc_write()/siw_proc_rresp() as
bytes = min(srx->fpdu_part_rem, srx->skb_new);
is handed to siw_check_mem() as an int len (whose interval check
addr + len > mem->va + mem->len is satisfied for a valid base when
len is negative), and reaches siw_rx_data() -> siw_rx_kva() /
siw_rx_umem() -> skb_copy_bits() as a signed copy length. The header
copy branch in skb_copy_bits() promotes that to size_t, producing a
multi-gigabyte read.
KASAN under a KUnit harness that drives the real kernel TCP receive
path -- a loopback AF_INET socketpair, the malformed FPDU written via
kernel_sendmsg, sk_data_ready firing in softirq, tcp_read_sock
dispatching to siw_tcp_rx_data -- reports:
BUG: KASAN: use-after-free in skb_copy_bits+0x284/0x480
Read of size 4294967295 at addr ffff888...
Call Trace:
skb_copy_bits
siw_rx_kva
siw_rx_data
siw_check_mem
siw_proc_write
siw_tcp_rx_data
__tcp_read_sock
siw_qp_llp_data_ready
tcp_data_ready
tcp_data_queue
Add the missing invariant at the earliest point where the peer header
is fully assembled. iwarp_pktinfo[*].hdr_len - MPA_HDR_SIZE is exactly
the value the siw transmitter uses as the minimum mpa_len for each
opcode (drivers/infiniband/sw/siw/siw_qp.c:33), so this matches the
protocol contract. Out-of-range FPDUs terminate the connection with
TERM_ERROR_LAYER_LLP / LLP_ETYPE_MPA / LLP_ECODE_FPDU_START -- which
is RFC 5044 Section 8 error code 3 ("Marker and ULPDU Length fields
do not agree on the start of an FPDU"), the correct framing-error
class for this inconsistency. |
