CVE-2026-80946
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: fuse: copy request headers via a stack buffer for io-uring The fuse-io-uring transport copies req->in.h out to the ring in fuse_uring_copy_to_ring() and req->out.h back in fuse_uring_commit(). Both headers live inside the fuse_request slab object, whose cache (fuse_req_cachep) is created without a usercopy whitelist, so copying them directly to/from userspace trips CONFIG_HARDENED_USERCOPY and panics: usercopy: Kernel memory exposure attempt detected from SLUB object 'fuse_request' (offset 56, size 40)! kernel BUG at mm/usercopy.c:102! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:usercopy_abort (mm/usercopy.c:90) Call Trace: __check_heap_object (mm/slub.c:8268) __check_object_size (mm/usercopy.c:197 mm/usercopy.c:258 mm/usercopy.c:223) copy_header_to_ring (fs/fuse/dev_uring.c:618) fuse_uring_prepare_send (fs/fuse/dev_uring.c:776 fs/fuse/dev_uring.c:785) fuse_uring_send_in_task (fs/fuse/dev_uring.c:1306) tctx_task_work_run (io_uring/tw.c:96) task_work_run (kernel/task_work.c:233) io_run_task_work (io_uring/tw.h:84) io_cqring_wait (io_uring/wait.c:278) __do_sys_io_uring_enter (io_uring/io_uring.c:2685) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) Bounce both headers through an on-stack copy so the usercopy touches stack memory, not the slab object.
View original CVE JSON
{
"id": "CVE-2026-80946",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-09-11T20:19:00.180",
"lastModified": "2026-10-19T09:17:25.933",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfuse: copy request headers via a stack buffer for io-uring\n\nThe fuse-io-uring transport copies req->in.h out to the ring in\nfuse_uring_copy_to_ring() and req->out.h back in fuse_uring_commit().\nBoth headers live inside the fuse_request slab object, whose cache\n(fuse_req_cachep) is created without a usercopy whitelist, so copying\nthem directly to/from userspace trips CONFIG_HARDENED_USERCOPY and\npanics:\n\n usercopy: Kernel memory exposure attempt detected from SLUB object\n 'fuse_request' (offset 56, size 40)!\n kernel BUG at mm/usercopy.c:102!\n Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\n RIP: 0010:usercopy_abort (mm/usercopy.c:90)\n Call Trace:\n __check_heap_object (mm/slub.c:8268)\n __check_object_size (mm/usercopy.c:197 mm/usercopy.c:258 mm/usercopy.c:223)\n copy_header_to_ring (fs/fuse/dev_uring.c:618)\n fuse_uring_prepare_send (fs/fuse/dev_uring.c:776 fs/fuse/dev_uring.c:785)\n fuse_uring_send_in_task (fs/fuse/dev_uring.c:1306)\n tctx_task_work_run (io_uring/tw.c:96)\n task_work_run (kernel/task_work.c:233)\n io_run_task_work (io_uring/tw.h:84)\n io_cqring_wait (io_uring/wait.c:278)\n __do_sys_io_uring_enter (io_uring/io_uring.c:2685)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n\nBounce both headers through an on-stack copy so the usercopy touches\nstack memory, not the slab object."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"fs/fuse/dev_uring.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "c090c8abae4b6b77a1bee116aa6c385456ebef96",
"lessThan": "194d0fb0ea4720535ff3168c9d04c7632cec7071",
"versionType": "git",
"status": "affected"
},
{
"version": "c090c8abae4b6b77a1bee116aa6c385456ebef96",
"lessThan": "a47a416ff68d706dc3327ab583f86b9ee757358b",
"versionType": "git",
"status": "affected"
},
{
"version": "c090c8abae4b6b77a1bee116aa6c385456ebef96",
"lessThan": "fd10f40af314f07b6d6e028b1ca25c8b49903aab",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"fs/fuse/dev_uring.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.14",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.14",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.51",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.4",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/194d0fb0ea4720535ff3168c9d04c7632cec7071",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a47a416ff68d706dc3327ab583f86b9ee757358b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/fd10f40af314f07b6d6e028b1ca25c8b49903aab",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}