In the Linux kernel, the following vulnerability has been resolved:
hugetlbfs: fix null-ptr-deref in hugetlbfsparseparam()
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:hugetlbfsparseparam+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380 [...] Call Trace: <TASK> vfsparsefsparam fs/fscontext.c:148 [inline] vfsparsefsparam+0x1f9/0x3c0 fs/fscontext.c:129 vfsparsefsstring+0xdb/0x170 fs/fscontext.c:191 genericparsemonolithic+0x16f/0x1f0 fs/fscontext.c:231 donewmount fs/namespace.c:3036 [inline] pathmount+0x12de/0x1e20 fs/namespace.c:3370 domount fs/namespace.c:3383 [inline] _dosysmount fs/namespace.c:3591 [inline] _sesysmount fs/namespace.c:3568 [inline] _x64sysmount+0x27f/0x300 fs/namespace.c:3568 dosyscallx64 arch/x86/entry/common.c:50 [inline] dosyscall64+0x35/0xb0 arch/x86/entry/common.c:80 entrySYSCALL64afterhwframe+0x63/0xcd [...]
According to commit "vfs: parse: deal with zero length string value", kernel will set the param->string to null pointer in vfsparsefs_string() if fs string has zero length.
Yet the problem is that, hugetlbfsparseparam() will dereference the param->string, without checking whether it is a null pointer. To be more specific, if hugetlbfsparseparam() parses an illegal mount parameter, such as "size=,", kernel will constructs struct fsparameter with null pointer in vfsparsefsstring(), then passes this struct fsparameter to hugetlbfsparse_param(), which triggers the above null-ptr-deref bug.
This patch solves it by adding sanity check on param->string in hugetlbfsparseparam().
[
{
"signature_type": "Line",
"digest": {
"threshold": 0.9,
"line_hashes": [
"139969619296543240540964656951886503827",
"313137673176807384689839966586614653294",
"187581991385767171583497982957522424183",
"254112480540043046345113834112087168048",
"77407634612816357246473120542466812911",
"301386967360257196005489960882763225667",
"109699476736554877998548511755791584488",
"81771463554457852722010411533640881365",
"117437615418036143385826223228683544424",
"163697902826027588620412365562500724527",
"256341533153278460091941911582985977824",
"200706702430854462636568330690273360642"
]
},
"target": {
"file": "fs/hugetlbfs/inode.c"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@fa71639873518e3587632ae58e25e4a96b57fa90",
"id": "CVE-2022-50334-03539844",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Function",
"digest": {
"function_hash": "157643726608831963670876998614925103425",
"length": 1581.0
},
"target": {
"file": "fs/hugetlbfs/inode.c",
"function": "hugetlbfs_parse_param"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@9a8862820cbf1f18dca4f3b4c289d88561b3a384",
"id": "CVE-2022-50334-0772d944",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Function",
"digest": {
"function_hash": "215637224453149063808795123955220270624",
"length": 1583.0
},
"target": {
"file": "fs/hugetlbfs/inode.c",
"function": "hugetlbfs_parse_param"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@f2207145693ae5697a7b59e2add4b92f9e5b0e3c",
"id": "CVE-2022-50334-101e1e73",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Function",
"digest": {
"function_hash": "157643726608831963670876998614925103425",
"length": 1581.0
},
"target": {
"file": "fs/hugetlbfs/inode.c",
"function": "hugetlbfs_parse_param"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@dcd28191be9bbf307ba51a5b485773a55b0037c4",
"id": "CVE-2022-50334-2f634970",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Function",
"digest": {
"function_hash": "35933471016405374584382750269969327172",
"length": 1594.0
},
"target": {
"file": "fs/hugetlbfs/inode.c",
"function": "hugetlbfs_parse_param"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@fa71639873518e3587632ae58e25e4a96b57fa90",
"id": "CVE-2022-50334-40d44c9a",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Function",
"digest": {
"function_hash": "215637224453149063808795123955220270624",
"length": 1583.0
},
"target": {
"file": "fs/hugetlbfs/inode.c",
"function": "hugetlbfs_parse_param"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@26215b7ee923b9251f7bb12c4e5f09dc465d35f2",
"id": "CVE-2022-50334-99497064",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Line",
"digest": {
"threshold": 0.9,
"line_hashes": [
"139969619296543240540964656951886503827",
"313137673176807384689839966586614653294",
"187581991385767171583497982957522424183",
"254112480540043046345113834112087168048",
"77407634612816357246473120542466812911",
"301386967360257196005489960882763225667",
"109699476736554877998548511755791584488",
"81771463554457852722010411533640881365",
"117437615418036143385826223228683544424",
"163697902826027588620412365562500724527",
"256341533153278460091941911582985977824",
"200706702430854462636568330690273360642"
]
},
"target": {
"file": "fs/hugetlbfs/inode.c"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@dcd28191be9bbf307ba51a5b485773a55b0037c4",
"id": "CVE-2022-50334-a02b64d9",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Line",
"digest": {
"threshold": 0.9,
"line_hashes": [
"139969619296543240540964656951886503827",
"313137673176807384689839966586614653294",
"187581991385767171583497982957522424183",
"254112480540043046345113834112087168048",
"77407634612816357246473120542466812911",
"301386967360257196005489960882763225667",
"109699476736554877998548511755791584488",
"81771463554457852722010411533640881365",
"117437615418036143385826223228683544424",
"163697902826027588620412365562500724527",
"256341533153278460091941911582985977824",
"200706702430854462636568330690273360642"
]
},
"target": {
"file": "fs/hugetlbfs/inode.c"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@26215b7ee923b9251f7bb12c4e5f09dc465d35f2",
"id": "CVE-2022-50334-b96e0670",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Line",
"digest": {
"threshold": 0.9,
"line_hashes": [
"139969619296543240540964656951886503827",
"313137673176807384689839966586614653294",
"187581991385767171583497982957522424183",
"254112480540043046345113834112087168048",
"77407634612816357246473120542466812911",
"301386967360257196005489960882763225667",
"109699476736554877998548511755791584488",
"81771463554457852722010411533640881365",
"117437615418036143385826223228683544424",
"163697902826027588620412365562500724527",
"256341533153278460091941911582985977824",
"200706702430854462636568330690273360642"
]
},
"target": {
"file": "fs/hugetlbfs/inode.c"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@9a8862820cbf1f18dca4f3b4c289d88561b3a384",
"id": "CVE-2022-50334-bb0bc820",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Line",
"digest": {
"threshold": 0.9,
"line_hashes": [
"139969619296543240540964656951886503827",
"313137673176807384689839966586614653294",
"187581991385767171583497982957522424183",
"254112480540043046345113834112087168048",
"77407634612816357246473120542466812911",
"301386967360257196005489960882763225667",
"109699476736554877998548511755791584488",
"81771463554457852722010411533640881365",
"117437615418036143385826223228683544424",
"163697902826027588620412365562500724527",
"256341533153278460091941911582985977824",
"200706702430854462636568330690273360642"
]
},
"target": {
"file": "fs/hugetlbfs/inode.c"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd",
"id": "CVE-2022-50334-d568df88",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Line",
"digest": {
"threshold": 0.9,
"line_hashes": [
"139969619296543240540964656951886503827",
"313137673176807384689839966586614653294",
"187581991385767171583497982957522424183",
"254112480540043046345113834112087168048",
"77407634612816357246473120542466812911",
"301386967360257196005489960882763225667",
"109699476736554877998548511755791584488",
"81771463554457852722010411533640881365",
"117437615418036143385826223228683544424",
"163697902826027588620412365562500724527",
"256341533153278460091941911582985977824",
"200706702430854462636568330690273360642"
]
},
"target": {
"file": "fs/hugetlbfs/inode.c"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@f2207145693ae5697a7b59e2add4b92f9e5b0e3c",
"id": "CVE-2022-50334-db050d31",
"deprecated": false,
"signature_version": "v1"
},
{
"signature_type": "Function",
"digest": {
"function_hash": "215637224453149063808795123955220270624",
"length": 1583.0
},
"target": {
"file": "fs/hugetlbfs/inode.c",
"function": "hugetlbfs_parse_param"
},
"source": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git@965e8f8ae0f642b5528f5a82b7bcaf15a659d5bd",
"id": "CVE-2022-50334-ecc0f496",
"deprecated": false,
"signature_version": "v1"
}
]