GHSA-3365-G9V5-8JG9
Vulnerability from github – Published: 2026-09-11 21:31 – Updated: 2026-09-11 21:31In the Linux kernel, the following vulnerability has been resolved:
iommu: Fix dev_iommu memory leak when device_add fails in iommu_mock_device_add
iommu_mock_device_add() first calls iommu_fwspec_init(), which on success allocates both dev->iommu (via dev_iommu_get()) and dev->iommu->fwspec. If the subsequent device_add(dev) call fails, the error path only calls iommu_fwspec_free(dev), which frees fwspec but leaves dev->iommu still allocated.
This triggers the following kmemleak report when fuzzing with Syzkaller:
BUG: memory leak unreferenced object 0xffff888011e0a200 (size 192): comm "syz.1.1695", pid 24885, jiffies 4295222527 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 ad 4e ad de .............N.. ff ff ff ff 00 00 00 00 ff ff ff ff ff ff ff ff ................ backtrace (crc 25df5bb3): kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline] slab_post_alloc_hook mm/slub.c:4575 [inline] slab_alloc_node mm/slub.c:4899 [inline] __kmalloc_cache_noprof+0x47a/0x710 mm/slub.c:5415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] dev_iommu_get+0x10c/0x1a0 drivers/iommu/iommu.c:408 iommu_fwspec_init+0x288/0x4d0 drivers/iommu/iommu.c:3087 iommu_mock_device_add+0x46/0xb0 drivers/iommu/iommu.c:385 mock_dev_create drivers/iommu/iommufd/selftest.c:1025 [inline] iommufd_test_mock_domain drivers/iommu/iommufd/selftest.c:1066 [inline] iommufd_test+0x2f8a/0x6190 drivers/iommu/iommufd/selftest.c:2072 iommufd_fops_ioctl+0x367/0x540 drivers/iommu/iommufd/main.c:533 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f
Fix this by calling dev_iommu_free(dev) instead of iommu_fwspec_free(dev) in the device_add() failure path. dev_iommu_free() frees both fwspec and the outer dev_iommu struct and clears dev->iommu.
{
"affected": [],
"aliases": [
"CVE-2026-89449"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-11T20:19:25Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu: Fix dev_iommu memory leak when device_add fails in iommu_mock_device_add\n\niommu_mock_device_add() first calls iommu_fwspec_init(), which on\nsuccess allocates both dev-\u003eiommu (via dev_iommu_get()) and\ndev-\u003eiommu-\u003efwspec. If the subsequent device_add(dev) call fails,\nthe error path only calls iommu_fwspec_free(dev), which frees\nfwspec but leaves dev-\u003eiommu still allocated.\n\nThis triggers the following kmemleak report when fuzzing with Syzkaller:\n\nBUG: memory leak\nunreferenced object 0xffff888011e0a200 (size 192):\n comm \"syz.1.1695\", pid 24885, jiffies 4295222527\n hex dump (first 32 bytes):\n 00 00 00 00 00 00 00 00 00 00 00 00 ad 4e ad de .............N..\n ff ff ff ff 00 00 00 00 ff ff ff ff ff ff ff ff ................\n backtrace (crc 25df5bb3):\n kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]\n slab_post_alloc_hook mm/slub.c:4575 [inline]\n slab_alloc_node mm/slub.c:4899 [inline]\n __kmalloc_cache_noprof+0x47a/0x710 mm/slub.c:5415\n kmalloc_noprof include/linux/slab.h:950 [inline]\n kzalloc_noprof include/linux/slab.h:1188 [inline]\n dev_iommu_get+0x10c/0x1a0 drivers/iommu/iommu.c:408\n iommu_fwspec_init+0x288/0x4d0 drivers/iommu/iommu.c:3087\n iommu_mock_device_add+0x46/0xb0 drivers/iommu/iommu.c:385\n mock_dev_create drivers/iommu/iommufd/selftest.c:1025 [inline]\n iommufd_test_mock_domain drivers/iommu/iommufd/selftest.c:1066 [inline]\n iommufd_test+0x2f8a/0x6190 drivers/iommu/iommufd/selftest.c:2072\n iommufd_fops_ioctl+0x367/0x540 drivers/iommu/iommufd/main.c:533\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:597 [inline]\n __se_sys_ioctl fs/ioctl.c:583 [inline]\n __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nFix this by calling dev_iommu_free(dev) instead of iommu_fwspec_free(dev)\nin the device_add() failure path. dev_iommu_free() frees both fwspec\nand the outer dev_iommu struct and clears dev-\u003eiommu.",
"id": "GHSA-3365-g9v5-8jg9",
"modified": "2026-09-11T21:31:26Z",
"published": "2026-09-11T21:31:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89449"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b7b0b3851474883d4aba6ed72da87141204b23e5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/eaf44262af24810d16800b988c92dfce90f73370"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f80f3acb69164800051ecdee871b6b006cbc2e66"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
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Nomenclature
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