{
  "threat_severity" : "Important",
  "public_date" : "2026-05-27T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: gfs2: Fix use-after-free in iomap inline data write path",
    "id" : "2481922",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2481922"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.8",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-826",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\ngfs2: Fix use-after-free in iomap inline data write path\nThe inline data buffer head (dibh) is being released prematurely in\ngfs2_iomap_begin() via release_metapath() while iomap->inline_data\nstill points to dibh->b_data. This causes a use-after-free when\niomap_write_end_inline() later attempts to write to the inline data\narea.\nThe bug sequence:\n1. gfs2_iomap_begin() calls gfs2_meta_inode_buffer() to read inode\nmetadata into dibh\n2. Sets iomap->inline_data = dibh->b_data + sizeof(struct gfs2_dinode)\n3. Calls release_metapath() which calls brelse(dibh), dropping refcount\nto 0\n4. kswapd reclaims the page (~39ms later in the syzbot report)\n5. iomap_write_end_inline() tries to memcpy() to iomap->inline_data\n6. KASAN detects use-after-free write to freed memory\nFix by storing dibh in iomap->private and incrementing its refcount\nwith get_bh() in gfs2_iomap_begin(). The buffer is then properly\nreleased in gfs2_iomap_end() after the inline write completes,\nensuring the page stays alive for the entire iomap operation.\nNote: A C reproducer is not available for this issue. The fix is based\non analysis of the KASAN report and code review showing the buffer head\nis freed before use.\n[agruenba: Take buffer head reference in gfs2_iomap_begin() to avoid\nleaks in gfs2_iomap_get() and gfs2_iomap_alloc().]", "A flaw was found in the Linux kernel's GFS2 filesystem. This memory corruption vulnerability, a use-after-free, occurs in the iomap inline data write path. The issue arises because a data buffer is released prematurely while still being referenced, leading to a write to freed memory. This could allow a local attacker to cause system instability or a denial of service (DoS)." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-06-22T00:00:00Z",
    "advisory" : "RHSA-2026:27789",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.17.1.el9_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-06-22T00:00:00Z",
    "advisory" : "RHSA-2026:27789",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.17.1.el9_8"
  } ],
  "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 10",
    "fix_state" : "Under investigation",
    "package_name" : "libkrun",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Under investigation",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux for NVIDIA 26",
    "fix_state" : "Under investigation",
    "package_name" : "kernel",
    "cpe" : "cpe:/a:redhat:enterprise_linux_nvidia:"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4",
    "fix_state" : "Under investigation",
    "package_name" : "rhcos",
    "cpe" : "cpe:/a:redhat:openshift:4"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-45984\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-45984\nhttps://lore.kernel.org/linux-cve-announce/2026052739-CVE-2026-45984-107d@gregkh/T" ],
  "name" : "CVE-2026-45984",
  "csaw" : false
}