dcache: Limit the minimal number of bucket to two
In the Linux kernel, the following vulnerability has been resolved: dcache: Limit the minimal number of bucket to two There is an OOB read problem on dentry_hashtable when user sets 'dhash_entries=1': BUG: unable to handle page fault for address: ffff888b30b774b0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page Oops: Oops: 0000 [#1] SMP PTI RIP: 0010:__d_lookup+0x56/0x120 Call Trace: d_lookup.cold+0x16/0x5d lookup_dcache+0x27/0xf0 lookup_one_qstr_excl+0x2a/0x180 start_dirop+0x55/0xa0 simple_start_creating+0x8d/0xa0 debugfs_start_creating+0x8c/0x180 debugfs_create_dir+0x1d/0x1c0 pinctrl_init+0x6d/0x140 do_one_initcall+0x6d/0x3d0 kernel_init_freeable+0x39f/0x460 kernel_init+0x2a/0x260 There will be only one bucket in dentry_hashtable when dhash_entries is set as one, and d_hash_shift is calculated as 32 by dcache_init(). Then, following process will access more than one buckets(which memory region is not allocated) in dentry_hashtable: d_lookup b = d_hash(hash) dentry_hashtable + ((u32)hashlen >> d_hash_shift) // The C standard defines the behavior of right shift amounts // exceeding the bit width of the operand as undefined. The // result of '(u32)hashlen >> d_hash_shift' becomes 'hashlen', // so 'b' will point to an unallocated memory region. hlist_bl_for_each_entry_rcu(b) hlist_bl_first_rcu(head) h->first // read OOB! Fix it by limiting the minimal number of dentry_hashtable bucket to two, so that 'd_hash_shift' won't exceeds the bit widt
CVE-2026-43071
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-2026-43071
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": "99d263d4c5b2f541dfacb5391e22e8c91ea982a6",
"lessThan": "45b06bb5ea96f75ad81d7ef446f832ea6b0026fe",
"versionType": "git"
},
{
"status": "affected",
"version": "99d263d4c5b2f541dfacb5391e22e8c91ea982a6",
"lessThan": "426ef05e82ee52c8d0e95fc0808b7383d8352d73",
"versionType": "git"
},
{
"status": "affected",
"version": "99d263d4c5b2f541dfacb5391e22e8c91ea982a6",
"lessThan": "ddd57ebce245f9c7e2f6902a6c087d6186d2385d",
"versionType": "git"
},
{
"status": "affected",
"version": "99d263d4c5b2f541dfacb5391e22e8c91ea982a6",
"lessThan": "755b40903eff563768d4d96fd4ef51ec48adde3b",
"versionType": "git"
},
{
"status": "affected",
"version": "99d263d4c5b2f541dfacb5391e22e8c91ea982a6",
"lessThan": "5718df131ab78897a9dd1f2e71c3ba732d4392af",
"versionType": "git"
},
{
"status": "affected",
"version": "99d263d4c5b2f541dfacb5391e22e8c91ea982a6",
"lessThan": "277cedabb0ab86baae83fa58218be13c6d3e5526",
"versionType": "git"
},
{
"status": "affected",
"version": "99d263d4c5b2f541dfacb5391e22e8c91ea982a6",
"lessThan": "f08fe8891c3eeb63b73f9f1f6d97aa629c821579",
"versionType": "git"
},
{
"status": "affected",
"version": "d4c96061fddd129778ce8b70fb093aa532f422d0",
"versionType": "git"
},
{
"status": "affected",
"version": "be2378cbffe50ce0161f0fdee914adee98af53dc",
"versionType": "git"
},
{
"status": "affected",
"version": "a8be8af18485f9fade90e1743d940252a39eec84",
"versionType": "git"
},
{
"status": "affected",
"version": "b5cf3193759f7cd1cfbeef11f5cf067bbce22e55",
"versionType": "git"
},
{
"status": "affected",
"version": "3.10.55",
"lessThan": "3.11",
"versionType": "semver"
},
{
"status": "affected",
"version": "3.12.29",
"lessThan": "3.13",
"versionType": "semver"
},
{
"status": "affected",
"version": "3.14.19",
"lessThan": "3.15",
"versionType": "semver"
},
{
"status": "affected",
"version": "3.16.3",
"lessThan": "3.17",
"versionType": "semver"
}
],
"programFiles": [
"fs/dcache.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.175",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.136",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.83",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.24",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.14",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0.1",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/dcache.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-43071
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #40018 · Revision 1
- Added to Heist Feed
- Publisher date