{"id":"CVE-2026-80720","state":"PUBLISHED","title":"iomap: add a separate bio_set for iomap_split_ioend","description":"In the Linux kernel, the following vulnerability has been resolved:\n\niomap: add a separate bio_set for iomap_split_ioend\n\niomap_split_ioend can split bios that already come from\niomap_ioend_bioset and thus deadlock when the bioset is exhausted.\n\nAdd a separate bio_set to avoid this deadlock.\n\nChristian Brauner <brauner@kernel.org> says:\nMark iomap_ioend_split_bioset static as it is only used in ioend.c,\nfixing the sparse warning reported by the kernel test robot.","publishedAt":"2026-08-28T06:53:16.683Z","updatedAt":"2026-08-29T06:22:35.780Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5fcbd555d48390a8c819ba7fdf55fbfcabe05c80","status":"affected","lessThan":"cfc686a1174aa904dcad9b9a7c5e46b484d27e4e","versionType":"git"},{"version":"5fcbd555d48390a8c819ba7fdf55fbfcabe05c80","status":"affected","lessThan":"4a869be56e9f6ce7462abcf324ebdefc5de051be","versionType":"git"},{"version":"5fcbd555d48390a8c819ba7fdf55fbfcabe05c80","status":"affected","lessThan":"c679ce3be6cb63763d68ab9b5d9d73ddc0a40762","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/iomap/ioend.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.15","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/iomap/ioend.c"]}],"references":["https://git.kernel.org/stable/c/cfc686a1174aa904dcad9b9a7c5e46b484d27e4e","https://git.kernel.org/stable/c/4a869be56e9f6ce7462abcf324ebdefc5de051be","https://git.kernel.org/stable/c/c679ce3be6cb63763d68ab9b5d9d73ddc0a40762"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80720.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80720","state":"PUBLISHED","datePublished":"2026-08-28T06:53:16.683Z","dateUpdated":"2026-08-29T06:22:35.780Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.788Z"},"containers":{"cna":{"title":"iomap: add a separate bio_set for iomap_split_ioend","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\niomap: add a separate bio_set for iomap_split_ioend\n\niomap_split_ioend can split bios that already come from\niomap_ioend_bioset and thus deadlock when the bioset is exhausted.\n\nAdd a separate bio_set to avoid this deadlock.\n\nChristian Brauner <brauner@kernel.org> says:\nMark iomap_ioend_split_bioset static as it is only used in ioend.c,\nfixing the sparse warning reported by the kernel test robot."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5fcbd555d48390a8c819ba7fdf55fbfcabe05c80","status":"affected","lessThan":"cfc686a1174aa904dcad9b9a7c5e46b484d27e4e","versionType":"git"},{"version":"5fcbd555d48390a8c819ba7fdf55fbfcabe05c80","status":"affected","lessThan":"4a869be56e9f6ce7462abcf324ebdefc5de051be","versionType":"git"},{"version":"5fcbd555d48390a8c819ba7fdf55fbfcabe05c80","status":"affected","lessThan":"c679ce3be6cb63763d68ab9b5d9d73ddc0a40762","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/iomap/ioend.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.15","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/iomap/ioend.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/cfc686a1174aa904dcad9b9a7c5e46b484d27e4e"},{"url":"https://git.kernel.org/stable/c/4a869be56e9f6ce7462abcf324ebdefc5de051be"},{"url":"https://git.kernel.org/stable/c/c679ce3be6cb63763d68ab9b5d9d73ddc0a40762"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - On ZNS-backed XFS realtime volumes exported via nfsd/ksmbd, remote client write I/O reaches vfs_write()->xfs_zone_alloc_and_submit()->iomap_split_ioend() in the server kernel without local shell access.\nAC:L - An attacker with write access can deterministically exhaust the 32-entry iomap_ioend_bioset via concurrent large zoned writes or direct I/O needing multiple bio_split allocations from the same pool; they control thread count and I/O size without uncontrollable races.\nPR:N - Triggering requires only permission to write realtime files on an XFS zoned filesystem via local syscall or network NFS/SMB client write; no CAP_SYS_ADMIN, ioctl, or init-namespace root is needed beyond write access to exported storage.\nUI:N - The attacker triggers the deadlock with their own concurrent write or direct-I/O requests; no separate victim must mount media, open a file, or perform any interactive action beyond the attacker's own I/O.\nS:U - The bioset mempool deadlock freezes zoned XFS I/O within the same host kernel security authority; it does not cross a VM, IOMMU, or sandbox boundary.\nC:N - This is a mempool self-deadlock with no memory corruption, out-of-bounds access, use-after-free, or information disclosure; bio_split failure returns -ENOMEM rather than leaking kernel data.\nI:N - The bug causes tasks to block indefinitely on mempool allocation but does not corrupt, modify, or overwrite file data or enable arbitrary writes or code execution.\nA:H - When iomap_ioend_bioset is exhausted, bio_split blocks on mempool_alloc() while holders cannot release entries, deadlocking writeback workers and zoned submit paths and hanging all I/O on the affected XFS zoned filesystem."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-29T06:22:35.780Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"6.18.44"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"7.1.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}