linux — security advisory
In the Linux kernel, the following vulnerability has been resolved: ext4: check dot and dotdot of dx_root before making dir indexed Syzbot reports a issue as follows: ============================================ BUG: unable to handle page fault for address: ffffed11022e24fe PGD 23ffee067 P4D 23ffee067 PUD 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 PID: 5079 Comm: syz-executor306 Not tainted 6.10.0-rc5-g55027e689933 #0 Call Trace: make_indexed_dir+0xdaf/0x13c0 fs/ext4/namei.c:2341 ext4_add_entry+0x222a/0x25d0 fs/ext4/namei.c:2451 ext4_rename fs/ext4/namei.c:3936 [inline] ext4_rename2+0x26e5/0x4370 fs/ext4/namei.c:4214 [...] ============================================ The immediate cause of this problem is that there is only one valid dentry for the block to be split during do_split, so split==0 results in out of bounds accesses to the map triggering the issue. do_split unsigned split dx_make_map count = 1 split = count/2 = 0; continued = hash2 == map[split - 1].hash; ---> map[4294967295] The maximum length of a filename is 255 and the minimum block size is 1024, so it is always guaranteed that the number of entries is greater than or equal to 2 when do_split() is called. But syzbot's crafted image has no dot and dotdot in dir, and the dentry distribution in dirblock is as follows: bus dentry1 hole dentry2 free |xx--|xx-------------|...............|xx-------------|...............| 0 12 (8+248)=256 268 256 524 (8+256)=264 788 236 1024 So when renaming dentry1 increase
- Products
- linux
- Affected versions
- 6.1.27-1, 6.1.37-1, 6.1.38-1, 6.1.38-2, 6.1.38-2~bpo11+1, 6.1.38-3, 6.1.38-4, 6.1.38-4~bpo11+1, 6.1.52-1, 6.1.55-1, 6.1.55-1~bpo11+1, 6.1.64-1, 6.1.66-1, 6.1.67-1, 6.1.69-1, 6.1.69-1~bpo11+1, 6.1.76-1, 6.1.76-1~bpo11+1, 6.1.82-1, 6.1.85-1, 6.1.90-1, 6.1.90-1~bpo11+1, 6.1.94-1, 6.1.94-1~bpo11+1, 6.1.98-1, 6.1.99-1
- Fixed versions
- 6.1.106-1, 6.10.3-1
- CVEs
- CVE-2024-42305
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 16:56 UTC · Revision 1
Source evidence
In the Linux kernel, the following vulnerability has been resolved: ext4: check dot and dotdot of dx_root before making dir indexed Syzbot reports a issue as follows: ============================================ BUG: unable to handle page fault for address: ffffed11022e24fe PGD 23ffee067 P4D 23ffee067 PUD 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 PID: 5079 Comm: syz-executor306 Not tainted 6.10.0-rc5-g55027e689933 #0 Call Trace: make_indexed_dir+0xdaf/0x13c0 fs/ext4/namei.c:2341 ext4_add_entry+0x222a/0x25d0 fs/ext4/namei.c:2451 ext4_rename fs/ext4/namei.c:3936 [inline] ext4_rename2+0x26e5/0x4370 fs/ext4/namei.c:4214 [...] ============================================ The immediate cause of this problem is that there is only one valid dentry for the block to be split during do_split, so split==0 results in out of bounds accesses to the map triggering the issue. do_split unsigned split dx_make_map count = 1 split = count/2 = 0; continued = hash2 == map[split - 1].hash; ---> map[4294967295] The maximum length of a filename is 255 and the minimum block size is 1024, so it is always guaranteed that the number of entries is greater than or equal to 2 when do_split() is called. But syzbot's crafted image has no dot and dotdot in dir, and the dentry distribution in dirblock is as follows: bus dentry1 hole dentry2 free |xx--|xx-------------|...............|xx-------------|...............| 0 12 (8+248)=256 268 256 524 (8+256)=264 788 236 1024 So when renaming dentry1 increase
osv:DEBIAN-CVE-2024-42305
linux
Fixed versions: 6.1.106-1
linux
Fixed versions: 6.10.3-1
linux
Fixed versions: 6.10.3-1
Complete source record
{
"id": "7e2642824e4bb2cb173234ace6d24d63882ced1f6362543e27e9d4b43714a18b",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2024-42305",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2024-42305",
"summary": "In the Linux kernel, the following vulnerability has been resolved: ext4: check dot and dotdot of dx_root before making dir indexed Syzbot reports a issue as follows: ============================================ BUG: unable to handle page fault for address: ffffed11022e24fe PGD 23ffee067 P4D 23ffee067 PUD 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 PID: 5079 Comm: syz-executor306 Not tainted 6.10.0-rc5-g55027e689933 #0 Call Trace: make_indexed_dir+0xdaf/0x13c0 fs/ext4/namei.c:2341 ext4_add_entry+0x222a/0x25d0 fs/ext4/namei.c:2451 ext4_rename fs/ext4/namei.c:3936 [inline] ext4_rename2+0x26e5/0x4370 fs/ext4/namei.c:4214 [...] ============================================ The immediate cause of this problem is that there is only one valid dentry for the block to be split during do_split, so split==0 results in out of bounds accesses to the map triggering the issue. do_split unsigned split dx_make_map count = 1 split = count/2 = 0; continued = hash2 == map[split - 1].hash; ---> map[4294967295] The maximum length of a filename is 255 and the minimum block size is 1024, so it is always guaranteed that the number of entries is greater than or equal to 2 when do_split() is called. But syzbot's crafted image has no dot and dotdot in dir, and the dentry distribution in dirblock is as follows: bus dentry1 hole dentry2 free |xx--|xx-------------|...............|xx-------------|...............| 0 12 (8+248)=256 268 256 524 (8+256)=264 788 236 1024 So when renaming dentry1 increase",
"evidence": "osv:DEBIAN-CVE-2024-42305",
"products": [
{
"name": {
"value": "linux",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "6.1.106-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "6.1.27-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.37-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.38-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.38-2",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.38-2~bpo11+1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.38-3",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.38-4",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.38-4~bpo11+1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.52-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.55-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.55-1~bpo11+1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.64-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.66-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.67-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.69-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.69-1~bpo11+1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.76-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.76-1~bpo11+1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.82-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.85-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.90-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.90-1~bpo11+1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.94-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.94-1~bpo11+1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.98-1",
"evidence": "/affected/0/versions"
},
{
"value": "6.1.99-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "linux",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "6.10.3-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "linux",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "6.10.3-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2024-42305",
"aliases": [
"DEBIAN-CVE-2024-42305"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "6.1.106-1"
}
]
}
],
"package": {
"name": "linux",
"purl": "pkg:deb/debian/linux?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"6.1.27-1",
"6.1.37-1",
"6.1.38-1",
"6.1.38-2",
"6.1.38-2~bpo11+1",
"6.1.38-3",
"6.1.38-4",
"6.1.38-4~bpo11+1",
"6.1.52-1",
"6.1.55-1",
"6.1.55-1~bpo11+1",
"6.1.64-1",
"6.1.66-1",
"6.1.67-1",
"6.1.69-1",
"6.1.69-1~bpo11+1",
"6.1.76-1",
"6.1.76-1~bpo11+1",
"6.1.82-1",
"6.1.85-1",
"6.1.90-1",
"6.1.90-1~bpo11+1",
"6.1.94-1",
"6.1.94-1~bpo11+1",
"6.1.98-1",
"6.1.99-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2024-42305.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "6.10.3-1"
}
]
}
],
"package": {
"name": "linux",
"purl": "pkg:deb/debian/linux?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2024-42305.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "6.10.3-1"
}
]
}
],
"package": {
"name": "linux",
"purl": "pkg:deb/debian/linux?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2024-42305.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-15T09:47:44.816083691Z",
"provider": "osv",
"upstream": [
"CVE-2024-42305"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2024-42305"
]
},
"related_cves": [
{
"value": "CVE-2024-42305",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 328608,
"published_at": "2024-08-17T09:15:10.69+00:00"
}