ghsa-pjr2-pwcr-ffrh
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
iommufd: Fix protection fault in iommufd_test_syz_conv_iova
Syzkaller reported the following bug:
general protection fault, probably for non-canonical address 0xdffffc0000000038: 0000 [#1] SMP KASAN KASAN: null-ptr-deref in range [0x00000000000001c0-0x00000000000001c7] Call Trace: lock_acquire lock_acquire+0x1ce/0x4f0 down_read+0x93/0x4a0 iommufd_test_syz_conv_iova+0x56/0x1f0 iommufd_test_access_rw.isra.0+0x2ec/0x390 iommufd_test+0x1058/0x1e30 iommufd_fops_ioctl+0x381/0x510 vfs_ioctl __do_sys_ioctl __se_sys_ioctl __x64_sys_ioctl+0x170/0x1e0 do_syscall_x64 do_syscall_64+0x71/0x140
This is because the new iommufd_access_change_ioas() sets access->ioas to NULL during its process, so the lock might be gone in a concurrent racing context.
Fix this by doing the same access->ioas sanity as iommufd_access_rw() and iommufd_access_pin_pages() functions do.
{
"affected": [],
"aliases": [
"CVE-2024-26785"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-04-04T09:15:08Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\niommufd: Fix protection fault in iommufd_test_syz_conv_iova\n\nSyzkaller reported the following bug:\n\n general protection fault, probably for non-canonical address 0xdffffc0000000038: 0000 [#1] SMP KASAN\n KASAN: null-ptr-deref in range [0x00000000000001c0-0x00000000000001c7]\n Call Trace:\n lock_acquire\n lock_acquire+0x1ce/0x4f0\n down_read+0x93/0x4a0\n iommufd_test_syz_conv_iova+0x56/0x1f0\n iommufd_test_access_rw.isra.0+0x2ec/0x390\n iommufd_test+0x1058/0x1e30\n iommufd_fops_ioctl+0x381/0x510\n vfs_ioctl\n __do_sys_ioctl\n __se_sys_ioctl\n __x64_sys_ioctl+0x170/0x1e0\n do_syscall_x64\n do_syscall_64+0x71/0x140\n\nThis is because the new iommufd_access_change_ioas() sets access-\u003eioas to\nNULL during its process, so the lock might be gone in a concurrent racing\ncontext.\n\nFix this by doing the same access-\u003eioas sanity as iommufd_access_rw() and\niommufd_access_pin_pages() functions do.",
"id": "GHSA-pjr2-pwcr-ffrh",
"modified": "2024-04-04T09:30:35Z",
"published": "2024-04-04T09:30:35Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-26785"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/cf7c2789822db8b5efa34f5ebcf1621bc0008d48"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fc719ecbca45c9c046640d72baddba3d83e0bc0b"
}
],
"schema_version": "1.4.0",
"severity": []
}