{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-42305","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-07-30T07:40:12.273Z","datePublished":"2024-08-17T09:09:11.296Z","dateUpdated":"2025-11-03T22:04:12.008Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T09:26:23.871Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: check dot and dotdot of dx_root before making dir indexed\n\nSyzbot reports a issue as follows:\n============================================\nBUG: unable to handle page fault for address: ffffed11022e24fe\nPGD 23ffee067 P4D 23ffee067 PUD 0\nOops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI\nCPU: 0 PID: 5079 Comm: syz-executor306 Not tainted 6.10.0-rc5-g55027e689933 #0\nCall Trace:\n <TASK>\n make_indexed_dir+0xdaf/0x13c0 fs/ext4/namei.c:2341\n ext4_add_entry+0x222a/0x25d0 fs/ext4/namei.c:2451\n ext4_rename fs/ext4/namei.c:3936 [inline]\n ext4_rename2+0x26e5/0x4370 fs/ext4/namei.c:4214\n[...]\n============================================\n\nThe immediate cause of this problem is that there is only one valid dentry\nfor the block to be split during do_split, so split==0 results in out of\nbounds accesses to the map triggering the issue.\n\n    do_split\n      unsigned split\n      dx_make_map\n       count = 1\n      split = count/2 = 0;\n      continued = hash2 == map[split - 1].hash;\n       ---> map[4294967295]\n\nThe maximum length of a filename is 255 and the minimum block size is 1024,\nso it is always guaranteed that the number of entries is greater than or\nequal to 2 when do_split() is called.\n\nBut syzbot's crafted image has no dot and dotdot in dir, and the dentry\ndistribution in dirblock is as follows:\n\n  bus     dentry1          hole           dentry2           free\n|xx--|xx-------------|...............|xx-------------|...............|\n0   12 (8+248)=256  268     256     524 (8+256)=264 788     236     1024\n\nSo when renaming dentry1 increases its name_len length by 1, neither hole\nnor free is sufficient to hold the new dentry, and make_indexed_dir() is\ncalled.\n\nIn make_indexed_dir() it is assumed that the first two entries of the\ndirblock must be dot and dotdot, so bus and dentry1 are left in dx_root\nbecause they are treated as dot and dotdot, and only dentry2 is moved\nto the new leaf block. That's why count is equal to 1.\n\nTherefore add the ext4_check_dx_root() helper function to add more sanity\nchecks to dot and dotdot before starting the conversion to avoid the above\nissue."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/namei.c"],"versions":[{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"b80575ffa98b5bb3a5d4d392bfe4c2e03e9557db","status":"affected","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"19e13b4d7f0303186fcc891aba8d0de7c8fdbda8","status":"affected","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"42d420517072028fb0eb852c358056b7717ba5aa","status":"affected","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"8afe06ed3be7a874b3cd82ef5f8959aca8d6429a","status":"affected","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"abb411ac991810c0bcbe51c2e76d2502bf611b5c","status":"affected","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"9d241b7a39af192d1bb422714a458982c7cc67a2","status":"affected","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"cdd345321699042ece4a9d2e70754d2397d378c5","status":"affected","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","lessThan":"50ea741def587a64e08879ce6c6a30131f7111e7","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/namei.c"],"versions":[{"version":"2.6.19","status":"affected"},{"version":"0","lessThan":"2.6.19","status":"unaffected","versionType":"semver"},{"version":"4.19.320","lessThanOrEqual":"4.19.*","status":"unaffected","versionType":"semver"},{"version":"5.4.282","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.224","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.165","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.103","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.44","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.10.3","lessThanOrEqual":"6.10.*","status":"unaffected","versionType":"semver"},{"version":"6.11","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"4.19.320"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"5.4.282"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"5.10.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"5.15.165"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"6.1.103"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"6.6.44"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"6.10.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"6.11"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/b80575ffa98b5bb3a5d4d392bfe4c2e03e9557db"},{"url":"https://git.kernel.org/stable/c/19e13b4d7f0303186fcc891aba8d0de7c8fdbda8"},{"url":"https://git.kernel.org/stable/c/42d420517072028fb0eb852c358056b7717ba5aa"},{"url":"https://git.kernel.org/stable/c/8afe06ed3be7a874b3cd82ef5f8959aca8d6429a"},{"url":"https://git.kernel.org/stable/c/abb411ac991810c0bcbe51c2e76d2502bf611b5c"},{"url":"https://git.kernel.org/stable/c/9d241b7a39af192d1bb422714a458982c7cc67a2"},{"url":"https://git.kernel.org/stable/c/cdd345321699042ece4a9d2e70754d2397d378c5"},{"url":"https://git.kernel.org/stable/c/50ea741def587a64e08879ce6c6a30131f7111e7"}],"title":"ext4: check dot and dotdot of dx_root before making dir indexed","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2024-42305","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-09-10T16:10:19.161352Z"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-09-12T17:33:27.970Z"}},{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"},{"url":"https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T22:04:12.008Z"}}]}}