{
  "public_date" : "2026-04-22T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: drm/amd/display: Do not skip unrelated mode changes in DSC validation",
    "id" : "2460619",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2460619"
  },
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\ndrm/amd/display: Do not skip unrelated mode changes in DSC validation\nStarting with commit 17ce8a6907f7 (\"drm/amd/display: Add dsc pre-validation in\natomic check\"), amdgpu resets the CRTC state mode_changed flag to false when\nrecomputing the DSC configuration results in no timing change for a particular\nstream.\nHowever, this is incorrect in scenarios where a change in MST/DSC configuration\nhappens in the same KMS commit as another (unrelated) mode change. For example,\nthe integrated panel of a laptop may be configured differently (e.g., HDR\nenabled/disabled) depending on whether external screens are attached. In this\ncase, plugging in external DP-MST screens may result in the mode_changed flag\nbeing dropped incorrectly for the integrated panel if its DSC configuration\ndid not change during precomputation in pre_validate_dsc().\nAt this point, however, dm_update_crtc_state() has already created new streams\nfor CRTCs with DSC-independent mode changes. In turn,\namdgpu_dm_commit_streams() will never release the old stream, resulting in a\nmemory leak. amdgpu_dm_atomic_commit_tail() will never acquire a reference to\nthe new stream either, which manifests as a use-after-free when the stream gets\ndisabled later on:\nBUG: KASAN: use-after-free in dc_stream_release+0x25/0x90 [amdgpu]\nWrite of size 4 at addr ffff88813d836524 by task kworker/9:9/29977\nWorkqueue: events drm_mode_rmfb_work_fn\nCall Trace:\n<TASK>\ndump_stack_lvl+0x6e/0xa0\nprint_address_description.constprop.0+0x88/0x320\n? dc_stream_release+0x25/0x90 [amdgpu]\nprint_report+0xfc/0x1ff\n? srso_alias_return_thunk+0x5/0xfbef5\n? __virt_addr_valid+0x225/0x4e0\n? dc_stream_release+0x25/0x90 [amdgpu]\nkasan_report+0xe1/0x180\n? dc_stream_release+0x25/0x90 [amdgpu]\nkasan_check_range+0x125/0x200\ndc_stream_release+0x25/0x90 [amdgpu]\ndc_state_destruct+0x14d/0x5c0 [amdgpu]\ndc_state_release.part.0+0x4e/0x130 [amdgpu]\ndm_atomic_destroy_state+0x3f/0x70 [amdgpu]\ndrm_atomic_state_default_clear+0x8ee/0xf30\n? drm_mode_object_put.part.0+0xb1/0x130\n__drm_atomic_state_free+0x15c/0x2d0\natomic_remove_fb+0x67e/0x980\nSince there is no reliable way of figuring out whether a CRTC has unrelated\nmode changes pending at the time of DSC validation, remember the value of the\nmode_changed flag from before the point where a CRTC was marked as potentially\naffected by a change in DSC configuration. Reset the mode_changed flag to this\nearlier value instead in pre_validate_dsc().\n(cherry picked from commit cc7c7121ae082b7b82891baa7280f1ff2608f22b)" ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-31488\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31488\nhttps://lore.kernel.org/linux-cve-announce/2026042200-CVE-2026-31488-fe04@gregkh/T" ],
  "name" : "CVE-2026-31488",
  "csaw" : false
}