{
  "threat_severity" : "Low",
  "public_date" : "2025-10-04T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: net: qrtr: Fix an uninit variable access bug in qrtr_tx_resume()",
    "id" : "2401492",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2401492"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-131",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnet: qrtr: Fix an uninit variable access bug in qrtr_tx_resume()\nSyzbot reported a bug as following:\n=====================================================\nBUG: KMSAN: uninit-value in qrtr_tx_resume+0x185/0x1f0 net/qrtr/af_qrtr.c:230\nqrtr_tx_resume+0x185/0x1f0 net/qrtr/af_qrtr.c:230\nqrtr_endpoint_post+0xf85/0x11b0 net/qrtr/af_qrtr.c:519\nqrtr_tun_write_iter+0x270/0x400 net/qrtr/tun.c:108\ncall_write_iter include/linux/fs.h:2189 [inline]\naio_write+0x63a/0x950 fs/aio.c:1600\nio_submit_one+0x1d1c/0x3bf0 fs/aio.c:2019\n__do_sys_io_submit fs/aio.c:2078 [inline]\n__se_sys_io_submit+0x293/0x770 fs/aio.c:2048\n__x64_sys_io_submit+0x92/0xd0 fs/aio.c:2048\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\nUninit was created at:\nslab_post_alloc_hook mm/slab.h:766 [inline]\nslab_alloc_node mm/slub.c:3452 [inline]\n__kmem_cache_alloc_node+0x71f/0xce0 mm/slub.c:3491\n__do_kmalloc_node mm/slab_common.c:967 [inline]\n__kmalloc_node_track_caller+0x114/0x3b0 mm/slab_common.c:988\nkmalloc_reserve net/core/skbuff.c:492 [inline]\n__alloc_skb+0x3af/0x8f0 net/core/skbuff.c:565\n__netdev_alloc_skb+0x120/0x7d0 net/core/skbuff.c:630\nqrtr_endpoint_post+0xbd/0x11b0 net/qrtr/af_qrtr.c:446\nqrtr_tun_write_iter+0x270/0x400 net/qrtr/tun.c:108\ncall_write_iter include/linux/fs.h:2189 [inline]\naio_write+0x63a/0x950 fs/aio.c:1600\nio_submit_one+0x1d1c/0x3bf0 fs/aio.c:2019\n__do_sys_io_submit fs/aio.c:2078 [inline]\n__se_sys_io_submit+0x293/0x770 fs/aio.c:2048\n__x64_sys_io_submit+0x92/0xd0 fs/aio.c:2048\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\nIt is because that skb->len requires at least sizeof(struct qrtr_ctrl_pkt)\nin qrtr_tx_resume(). And skb->len equals to size in qrtr_endpoint_post().\nBut size is less than sizeof(struct qrtr_ctrl_pkt) when qrtr_cb->type\nequals to QRTR_TYPE_RESUME_TX in qrtr_endpoint_post() under the syzbot\nscenario. This triggers the uninit variable access bug.\nAdd size check when qrtr_cb->type equals to QRTR_TYPE_RESUME_TX in\nqrtr_endpoint_post() to fix the bug.", "An uninitialized memory access flaw was found in the Linux kernel's QRTR (Qualcomm IPC Router) protocol in the transmit resume handling. When processing RESUME_TX messages, if the packet size is smaller than the expected control structure, the qrtr_tx_resume function reads uninitialized memory from the skb buffer. This can lead to unpredictable behavior, kernel warnings from KMSAN (Kernel Memory Sanitizer), and potential crashes, causing denial of service." ],
  "statement" : "QRTR is a message-based IPC mechanism used in Qualcomm SoCs to communicate between processors and subsystems. The protocol uses control messages for flow control, including QRTR_TYPE_RESUME_TX packets that signal readiness to receive more data. The qrtr_tx_resume function expects these packets to contain at least a full qrtr_ctrl_pkt structure and reads fields from that structure. Meanwhile, qrtr_endpoint_post allocates an skb of size 'size' (from the received message) and sets skb->len to match. When a malformed or crafted message arrives with type QRTR_TYPE_RESUME_TX but size less than sizeof(struct qrtr_ctrl_pkt), the allocated skb doesn't contain enough initialized data. When qrtr_tx_resume tries to access fields of the control packet, it reads beyond the initialized portion into whatever random data happened to be in that memory.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2021-11-09T00:00:00Z",
    "advisory" : "RHSA-2021:4356",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-348.el8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2023-11-14T00:00:00Z",
    "advisory" : "RHSA-2023:7077",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-513.5.1.el8_9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-11-07T00:00:00Z",
    "advisory" : "RHSA-2023:6583",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-362.8.1.el9_3"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-11-07T00:00:00Z",
    "advisory" : "RHSA-2023:6583",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-362.8.1.el9_3"
  } ],
  "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" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2023-53578\nhttps://nvd.nist.gov/vuln/detail/CVE-2023-53578\nhttps://lore.kernel.org/linux-cve-announce/2025100455-CVE-2023-53578-7dbf@gregkh/T" ],
  "name" : "CVE-2023-53578",
  "csaw" : false
}