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Ubuntu: (CVE-2021-4439): linux vulnerability

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Ubuntu: (CVE-2021-4439): linux vulnerability

Severity
4
CVSS
(AV:L/AC:M/Au:N/C:P/I:P/A:P)
Published
06/20/2024
Created
11/21/2024
Added
11/19/2024
Modified
11/19/2024

Description

In the Linux kernel, the following vulnerability has been resolved: isdn: cpai: check ctr->cnr to avoid array index out of bound The cmtp_add_connection() would add a cmtp session to a controller and run a kernel thread to process cmtp. __module_get(THIS_MODULE); session->task = kthread_run(cmtp_session, session, "kcmtpd_ctr_%d", session->num); During this process, the kernel thread would call detach_capi_ctr() to detach a register controller. if the controller was not attached yet, detach_capi_ctr() would trigger an array-index-out-bounds bug. [ 46.866069][ T6479] UBSAN: array-index-out-of-bounds in drivers/isdn/capi/kcapi.c:483:21 [ 46.867196][ T6479] index -1 is out of range for type 'capi_ctr *[32]' [ 46.867982][ T6479] CPU: 1 PID: 6479 Comm: kcmtpd_ctr_0 Not tainted 5.15.0-rc2+ #8 [ 46.869002][ T6479] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 [ 46.870107][ T6479] Call Trace: [ 46.870473][ T6479] dump_stack_lvl+0x57/0x7d [ 46.870974][ T6479] ubsan_epilogue+0x5/0x40 [ 46.871458][ T6479] __ubsan_handle_out_of_bounds.cold+0x43/0x48 [ 46.872135][ T6479] detach_capi_ctr+0x64/0xc0 [ 46.872639][ T6479] cmtp_session+0x5c8/0x5d0 [ 46.873131][ T6479] ? __init_waitqueue_head+0x60/0x60 [ 46.873712][ T6479] ? cmtp_add_msgpart+0x120/0x120 [ 46.874256][ T6479] kthread+0x147/0x170 [ 46.874709][ T6479] ? set_kthread_struct+0x40/0x40 [ 46.875248][ T6479] ret_from_fork+0x1f/0x30 [ 46.875773][ T6479]

Solution(s)

  • ubuntu-upgrade-linux
  • ubuntu-upgrade-linux-aws
  • ubuntu-upgrade-linux-aws-5-4
  • ubuntu-upgrade-linux-aws-hwe
  • ubuntu-upgrade-linux-azure
  • ubuntu-upgrade-linux-azure-4-15
  • ubuntu-upgrade-linux-azure-5-4
  • ubuntu-upgrade-linux-bluefield
  • ubuntu-upgrade-linux-gcp
  • ubuntu-upgrade-linux-gcp-4-15
  • ubuntu-upgrade-linux-gcp-5-4
  • ubuntu-upgrade-linux-gkeop
  • ubuntu-upgrade-linux-hwe
  • ubuntu-upgrade-linux-hwe-5-4
  • ubuntu-upgrade-linux-ibm
  • ubuntu-upgrade-linux-kvm
  • ubuntu-upgrade-linux-lts-xenial
  • ubuntu-upgrade-linux-oracle
  • ubuntu-upgrade-linux-oracle-5-4
  • ubuntu-upgrade-linux-raspi
  • ubuntu-upgrade-linux-raspi-5-4

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