Уязвимости linux-lowlatency-hwe-5.15 · Страница 109

kcm: use WRITE_ONCE() when changing lower socket callbacks

In the Linux kernel, the following vulnerability has been resolved: kcm: use WRITE_ONCE() when changing lower socket callbacks kcm_attach() replaces a live lower TCP socket's sk_data_ready and sk_write_space callbacks with KCM handlers, and kcm_unattach() restores them later. Those callback-pointer updates are still plain stores even though the same fields can be read and invoked concurrently on other CPUs. If another CPU observes an older callback snapshot after the live field has already been restored, callback execution can run with a mismatched target and sk_user_data state, leading to stale or misdirected wakeups. Use WRITE_ONCE() fo

• Обновитесь до 5.15.0-195.205~20.04.1

ALSA: seq: avoid stale FIFO cells during resize

In the Linux kernel, the following vulnerability has been resolved: ALSA: seq: avoid stale FIFO cells during resize snd_seq_fifo_resize() still needs to publish the replacement pool before it waits for FIFO users. A blocking snd_seq_read() holds f->use_lock while it sleeps, so concurrent senders must be able to queue to the new pool and wake that reader instead of failing against a closing old pool. However, snd_seq_fifo_event_in() duplicates an event before it takes f->lock, and snd_seq_read() can dequeue a cell and later call snd_seq_fifo_cell_putback() if copy_to_user() or snd_seq_expand_var_event() fails. If resize swaps f->pool and de

sockmap: Fix use-after-free in udp_bpf_recvmsg()

In the Linux kernel, the following vulnerability has been resolved: sockmap: Fix use-after-free in udp_bpf_recvmsg() syzbot reported use-after-free of struct sk_msg in sk_msg_recvmsg(). [0] sk_msg_recvmsg() peeks sk_msg from psock->ingress_msg under a lock, but its processing is lockless. Thus, sk_msg_recvmsg() must be serialised by callers, otherwise multiple threads could touch the same sk_msg. For example, TCP uses lock_sock(), and AF_UNIX uses unix_sk(sk)->iolock. Initially, udp_bpf_recvmsg() had used lock_sock(), but the cited commit removed it. Let's serialise sk_msg_recvmsg() with lock_sock() in udp_bpf_recvmsg(). Note that hol

bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check

In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check start and len are u32, so u64 last = start + len; evaluates start + len in 32-bit and wraps before storing it in last. The bounds check if (start >= offset + l || last > msg->sg.size) return -EINVAL; can then be passed with an out-of-range start/len, after which the pop loop runs off the end of the scatterlist and sk_msg_shift_left() calls put_page() on the empty msg->sg.end slot: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN PTI

• Обновитесь до 5.15.0-195.205~20.04.1

tipc: fix UAF in tipc_l2_send_msg()

In the Linux kernel, the following vulnerability has been resolved: tipc: fix UAF in tipc_l2_send_msg() Syzbot reported a slab-use-after-free in ipvlan_hard_header() when called from tipc_l2_send_msg(). The root cause is that tipc_disable_l2_media() calls synchronize_net() while b->media_ptr is still valid. This allows concurrent RCU readers to obtain the device pointer after synchronize_net() has finished. The pointer is cleared later in bearer_disable(), but without any subsequent synchronization, allowing the device to be freed while still in use by readers. Fix this by clearing b->media_ptr in tipc_disable_l2_media() before calling sy

• Обновитесь до 5.15.0-195.205~20.04.1

tcp: ipv6: clamp default adverting MSS to avoid GSO_BY_FRAGS (0xFFFF)

In the Linux kernel, the following vulnerability has been resolved: tcp: ipv6: clamp default adverting MSS to avoid GSO_BY_FRAGS (0xFFFF) When MTU is large, ip6_default_advmss() can return IPV6_MAXPLEN (65535). This is interpreted by TCP as mss_clamp, allowing the MSS to reach 65535. However, 0xFFFF is also used as a magic value GSO_BY_FRAGS in the kernel. If a TCP packet with gso_size=0xFFFF is passed to skb_segment(), it will be mistakenly treated as GSO_BY_FRAGS, leading to a NULL pointer dereference because local TCP packets do not use frag_list. Fix this by returning min(IPV6_MAXPLEN, GSO_BY_FRAGS - 1) (65534) from ip6_default_advmss

• Обновитесь до 5.15.0-195.205~20.04.1

RDMA/irdma: Replace waitqueue and flag with completion

In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Replace waitqueue and flag with completion The driver previously used a waitqueue along with an explicit request_done flag, but without proper barriers around request_done. An earlier patch by Gui-Dong Han <hanguidong02@gmail.com> attempted to fix this by adding the missing memory barriers. Rather than adding the barriers, this patch replaces the waitqueue+flag with a completion, which is designed for this exact purpose.

net: serialize netif_running() check in enqueue_to_backlog()

In the Linux kernel, the following vulnerability has been resolved: net: serialize netif_running() check in enqueue_to_backlog() Syzbot reported a KASAN slab-use-after-free in fib_rules_lookup(). The root cause is a race condition where packets can escape the backlog flushing during device unregistration (e.g., during netns exit). Commit e9e4dd3267d0 ("net: do not process device backlog during unregistration") introduced a lockless netif_running() check in enqueue_to_backlog() to prevent queuing packets to an unregistering device. However, this creates a TOCTOU race window. A lockless transmitter (like veth_xmit) can pass the check befo

ksmbd: fix use-after-free in same_client_has_lease()

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in same_client_has_lease() same_client_has_lease() returns an opinfo pointer from ci->m_op_list after dropping ci->m_lock without taking a reference. smb_grant_oplock() then dereferences that pointer in copy_lease() and when checking breaking_cnt. A concurrent close can remove the old lease from ci->m_op_list and drop the last reference before the caller uses the returned pointer, leading to a use-after-free. Take a reference when same_client_has_lease() selects an existing lease, drop any previous match while scanning, and release the returned r

• Обновитесь до 5.15.0-195.205~20.04.1

net/9p: fix race condition on rdma->state in trans_rdma.c

In the Linux kernel, the following vulnerability has been resolved: net/9p: fix race condition on rdma->state in trans_rdma.c The rdma->state field is modified without holding req_lock in both recv_done() and p9_cm_event_handler(), while rdma_request() accesses the same field under the req_lock spinlock. This inconsistent locking creates a race condition: - recv_done() running in softirq completion context sets rdma->state = P9_RDMA_FLUSHING without acquiring req_lock - p9_cm_event_handler() modifies rdma->state at multiple points (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without req_lock - rdma_request() uses spin_lock_

• Обновитесь до 5.15.0-195.205~20.04.1

staging: nvec: fix use-after-free in nvec_rx_completed()

In the Linux kernel, the following vulnerability has been resolved: staging: nvec: fix use-after-free in nvec_rx_completed() In nvec_rx_completed(), when an incomplete RX transfer is detected, nvec_msg_free() is called to return the message back to the pool by clearing its 'used' atomic flag. Immediately after this, the code accesses nvec->rx->data[0] to check the message type. Since nvec_msg_free() marks the pool slot as available via atomic_set(), any concurrent or subsequent call to nvec_msg_alloc() could claim that same slot and overwrite its data[] array. Reading nvec->rx->data[0] after freeing the message is therefore a use-after-fre

• Обновитесь до 5.15.0-195.205~20.04.1

soundwire: fix bug in sdw_add_element_group_count found by syzkaller

In the Linux kernel, the following vulnerability has been resolved: soundwire: fix bug in sdw_add_element_group_count found by syzkaller The original implementation caused an out-of-bounds memory access in the sdw_add_element_group_count for-loop when i == num. for (i = 0; i <= num; i++) { if (rate == group->rates[i] && lane == group->lanes[i]) ... To fix this error, the function now checks for existing rate/lane entries in the group(a function parameter) using a for-loop before adding them. No functional changes apart from this fix.

PCI: Check ROM header and data structure addr before accessing

In the Linux kernel, the following vulnerability has been resolved: PCI: Check ROM header and data structure addr before accessing We meet a crash when running stress-ng on x86_64 machine: BUG: unable to handle page fault for address: ffa0000007f40000 RIP: 0010:pci_get_rom_size+0x52/0x220 Call Trace: <TASK> pci_map_rom+0x80/0x130 pci_read_rom+0x4b/0xe0 kernfs_file_read_iter+0x96/0x180 vfs_read+0x1b1/0x300 Our analysis reveals that the ROM space's start address is 0xffa0000007f30000, and size is 0x10000. Because of broken ROM space, before calling readl(pds), the pds's value is 0xffa0000007f3ffff, which is already p

staging: most: video: avoid double free on video register failure

In the Linux kernel, the following vulnerability has been resolved: staging: most: video: avoid double free on video register failure comp_register_videodev() allocates a video_device with video_device_alloc() and releases it if video_register_device() fails. This can double free the video_device when __video_register_device() reaches device_register() and that call fails: video_register_device() -> __video_register_device() -> device_register() fails -> put_device(&vdev->dev) -> v4l2_device_release() -> vdev->release(vdev) -> video_device_release(vdev) comp_registe

• Обновитесь до 5.15.0-195.205~20.04.1

usb: host: max3421: Fix shift-out-of-bounds in max3421_hub_control()

In the Linux kernel, the following vulnerability has been resolved: usb: host: max3421: Fix shift-out-of-bounds in max3421_hub_control() The `max3421_hub_control()` function handles USB hub class requests to the virtual root hub. In the `default` branches of both the `ClearPortFeature` and `SetPortFeature` switch statements, it modifies `max3421_hcd->port_status` by left shifting 1 by the request's `value` parameter. However, it does not validate whether this shift will exceed the width of `port_status`. So if a malicious userspace task with access to the root hub via /dev/bus/usb/.../001 issues a USBDEVFS_CONTROL ioctl with `wValue` great

• Обновитесь до 5.15.0-195.205~20.04.1

iio: magnetometer: ak8975: fix potential kernel stack memory leak

In the Linux kernel, the following vulnerability has been resolved: iio: magnetometer: ak8975: fix potential kernel stack memory leak Currently in the AK8975 driver there are four instances where potential uninitialized kernel stack memory leaks can occur. If i2c_smbus_read_i2c_block_data_or_emulated() returns a value less than the size of the buffer, uninitialized bytes are retained in the buffer and later the buffer is passed on to IIO buffers, potentially leaking memory to userspace. Fix this by adding checks whether the return value of the function is equal to the size of the buffer and subsequently if the value is lesser than zero to

• Обновитесь до 5.15.0-195.205~20.04.1

iio: accel: mma8452: handle I2C read error(s) in mma8452_read()

In the Linux kernel, the following vulnerability has been resolved: iio: accel: mma8452: handle I2C read error(s) in mma8452_read() Currently, If i2c_smbus_read_i2c_block_data() fails but mma8452_set_runtime_pm_state() succeeds, mma8452_read() returns 0. As a result, the caller mma8452_read_raw() assumes the read was successful and proceeds to use a buffer containing uninitialized stack memory. Add proper checking of the I2C read return value and propagate errors to the caller.

• Обновитесь до 5.15.0-195.205~20.04.1

fs/ntfs3: add bounds check to run_get_highest_vcn()

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: add bounds check to run_get_highest_vcn() run_get_highest_vcn() parses a packed NTFS mapping-pairs buffer without any length bound, relying solely on a 0x00 terminator to stop. A crafted $LogFile UpdateMappingPairs record whose embedded attribute contains mapping-pairs runs without a terminator causes the function to read past the slab allocation, triggering a KASAN slab-out-of-bounds read on mount. The sibling function run_unpack() received an analogous bounds-check in commit b62567bca474 ("ntfs3: add buffer boundary checks to run_unpack()"), but run_get_highes

dmaengine: Fix possible use after free

In the Linux kernel, the following vulnerability has been resolved: dmaengine: Fix possible use after free In dma_release_channel(), check chan->device->privatecnt after call dma_chan_put(). However, dma_chan_put() call dma_device_put() which could release the last reference of the device if the DMA provider is already gone and hence free it. Fixes it by moving dma_chan_put() after the check.

• Обновитесь до 5.15.0-195.205~20.04.1

xprtrdma: Decouple req recycling from RPC completion

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Decouple req recycling from RPC completion rl_kref formerly served two distinct lifetimes through a single refcount: it gated when a Reply could wake its RPC task, and it gated when an rpcrdma_req could return to its free pool. The marshal path took the Send-side reference only when SGEs needed DMA-unmap (sc_unmap_count > 0), which made a Send carrying only pre-registered buffers an exception: the Reply handler dropped rl_kref from 1 to 0 and freed the req while the HCA might still be DMA-reading from its send buffer. Give rl_kref a narrower job. The RPC layer ta