{
  "threat_severity" : "Low",
  "public_date" : "2025-02-26T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: list: fix a data-race around ep->rdllist",
    "id" : "2348240",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2348240"
  },
  "cvss3" : {
    "cvss3_base_score" : "4.7",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-362",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nlist: fix a data-race around ep->rdllist\nep_poll() first calls ep_events_available() with no lock held and checks\nif ep->rdllist is empty by list_empty_careful(), which reads\nrdllist->prev.  Thus all accesses to it need some protection to avoid\nstore/load-tearing.\nNote INIT_LIST_HEAD_RCU() already has the annotation for both prev\nand next.\nCommit bf3b9f6372c4 (\"epoll: Add busy poll support to epoll with socket\nfds.\") added the first lockless ep_events_available(), and commit\nc5a282e9635e (\"fs/epoll: reduce the scope of wq lock in epoll_wait()\")\nmade some ep_events_available() calls lockless and added single call under\na lock, finally commit e59d3c64cba6 (\"epoll: eliminate unnecessary lock\nfor zero timeout\") made the last ep_events_available() lockless.\nBUG: KCSAN: data-race in do_epoll_wait / do_epoll_wait\nwrite to 0xffff88810480c7d8 of 8 bytes by task 1802 on cpu 0:\nINIT_LIST_HEAD include/linux/list.h:38 [inline]\nlist_splice_init include/linux/list.h:492 [inline]\nep_start_scan fs/eventpoll.c:622 [inline]\nep_send_events fs/eventpoll.c:1656 [inline]\nep_poll fs/eventpoll.c:1806 [inline]\ndo_epoll_wait+0x4eb/0xf40 fs/eventpoll.c:2234\ndo_epoll_pwait fs/eventpoll.c:2268 [inline]\n__do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]\n__se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275\n__x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x44/0xae\nread to 0xffff88810480c7d8 of 8 bytes by task 1799 on cpu 1:\nlist_empty_careful include/linux/list.h:329 [inline]\nep_events_available fs/eventpoll.c:381 [inline]\nep_poll fs/eventpoll.c:1797 [inline]\ndo_epoll_wait+0x279/0xf40 fs/eventpoll.c:2234\ndo_epoll_pwait fs/eventpoll.c:2268 [inline]\n__do_sys_epoll_pwait fs/eventpoll.c:2281 [inline]\n__se_sys_epoll_pwait+0x12b/0x240 fs/eventpoll.c:2275\n__x64_sys_epoll_pwait+0x74/0x80 fs/eventpoll.c:2275\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x44/0xae\nvalue changed: 0xffff88810480c7d0 -> 0xffff888103c15098\nReported by Kernel Concurrency Sanitizer on:\nCPU: 1 PID: 1799 Comm: syz-fuzzer Tainted: G        W         5.17.0-rc7-syzkaller-dirty #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011" ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20518",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.5.1.el9_7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20518",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.5.1.el9_7"
  } ],
  "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" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Out of support scope",
    "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-2022-49443\nhttps://nvd.nist.gov/vuln/detail/CVE-2022-49443\nhttps://lore.kernel.org/linux-cve-announce/2025022658-CVE-2022-49443-15cc@gregkh/T" ],
  "name" : "CVE-2022-49443",
  "csaw" : false
}