ext4: check dot and dotdot of dx_root before making dir indexed
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
CVE-2024-42305
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2024-42305
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "b80575ffa98b5bb3a5d4d392bfe4c2e03e9557db",
"versionType": "git"
},
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "19e13b4d7f0303186fcc891aba8d0de7c8fdbda8",
"versionType": "git"
},
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "42d420517072028fb0eb852c358056b7717ba5aa",
"versionType": "git"
},
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "8afe06ed3be7a874b3cd82ef5f8959aca8d6429a",
"versionType": "git"
},
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "abb411ac991810c0bcbe51c2e76d2502bf611b5c",
"versionType": "git"
},
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "9d241b7a39af192d1bb422714a458982c7cc67a2",
"versionType": "git"
},
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "cdd345321699042ece4a9d2e70754d2397d378c5",
"versionType": "git"
},
{
"status": "affected",
"version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571",
"lessThan": "50ea741def587a64e08879ce6c6a30131f7111e7",
"versionType": "git"
}
],
"programFiles": [
"fs/ext4/namei.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.19"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.19",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "4.19.320",
"versionType": "semver",
"lessThanOrEqual": "4.19.*"
},
{
"status": "unaffected",
"version": "5.4.282",
"versionType": "semver",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.224",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.165",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.103",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.44",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.10.3",
"versionType": "semver",
"lessThanOrEqual": "6.10.*"
},
{
"status": "unaffected",
"version": "6.11",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/ext4/namei.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2024-42305
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #26683 · Revision 1
- Added to Heist Feed
- Publisher date