VULNERABILITY

Ubuntu: (CVE-2021-4454): linux vulnerability

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Ubuntu: (CVE-2021-4454): linux vulnerability

Severity
5
CVSS
(AV:L/AC:L/Au:S/C:N/I:N/A:C)
Published
03/27/2025
Created
04/02/2025
Added
04/01/2025
Modified
04/03/2025

Description

In the Linux kernel, the following vulnerability has been resolved: can: j1939: fix errant WARN_ON_ONCE in j1939_session_deactivate The conclusion "j1939_session_deactivate() should be called with a session ref-count of at least 2" is incorrect. In some concurrent scenarios, j1939_session_deactivate can be called with the session ref-count less than 2. But there is not any problem because it will check the session active state before session putting in j1939_session_deactivate_locked(). Here is the concurrent scenario of the problem reported by syzbot and my reproduction log. cpu0 cpu1 j1939_xtp_rx_eoma j1939_xtp_rx_abort_one j1939_session_get_by_addr [kref == 2] j1939_session_get_by_addr [kref == 3] j1939_session_deactivate [kref == 2] j1939_session_put [kref == 1] j1939_session_completed j1939_session_deactivate WARN_ON_ONCE(kref < 2) ===================================================== WARNING: CPU: 1 PID: 21 at net/can/j1939/transport.c:1088 j1939_session_deactivate+0x5f/0x70 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 5.14.0-rc7+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014 RIP: 0010:j1939_session_deactivate+0x5f/0x70 Call Trace: j1939_session_deactivate_activate_next+0x11/0x28 j1939_xtp_rx_eoma+0x12a/0x180 j1939_tp_recv+0x4a2/0x510 j1939_can_recv+0x226/0x380 can_rcv_filter+0xf8/0x220 can_receive+0x102/0x220 ? process_backlog+0xf0/0x2c0 can_rcv+0x53/0xf0 __netif_receive_skb_one_core+0x67/0x90 ? process_backlog+0x97/0x2c0 __netif_receive_skb+0x22/0x80

Solution(s)

  • ubuntu-upgrade-linux
  • ubuntu-upgrade-linux-aws
  • ubuntu-upgrade-linux-aws-5-15
  • ubuntu-upgrade-linux-aws-5-4
  • ubuntu-upgrade-linux-aws-fips
  • ubuntu-upgrade-linux-azure
  • ubuntu-upgrade-linux-azure-5-15
  • ubuntu-upgrade-linux-azure-5-4
  • ubuntu-upgrade-linux-azure-fips
  • ubuntu-upgrade-linux-bluefield
  • ubuntu-upgrade-linux-fips
  • ubuntu-upgrade-linux-gcp
  • ubuntu-upgrade-linux-gcp-5-15
  • ubuntu-upgrade-linux-gcp-5-4
  • ubuntu-upgrade-linux-gcp-fips
  • ubuntu-upgrade-linux-gke
  • ubuntu-upgrade-linux-gkeop
  • ubuntu-upgrade-linux-hwe-5-15
  • ubuntu-upgrade-linux-hwe-5-4
  • ubuntu-upgrade-linux-ibm
  • ubuntu-upgrade-linux-ibm-5-4
  • ubuntu-upgrade-linux-intel-iot-realtime
  • ubuntu-upgrade-linux-intel-iotg
  • ubuntu-upgrade-linux-intel-iotg-5-15
  • ubuntu-upgrade-linux-iot
  • ubuntu-upgrade-linux-kvm
  • ubuntu-upgrade-linux-lowlatency
  • ubuntu-upgrade-linux-lowlatency-hwe-5-15
  • ubuntu-upgrade-linux-nvidia
  • ubuntu-upgrade-linux-oracle
  • ubuntu-upgrade-linux-oracle-5-15
  • ubuntu-upgrade-linux-oracle-5-4
  • ubuntu-upgrade-linux-raspi
  • ubuntu-upgrade-linux-raspi-5-4
  • ubuntu-upgrade-linux-realtime
  • ubuntu-upgrade-linux-riscv-5-15
  • ubuntu-upgrade-linux-xilinx-zynqmp

References

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