{"id":"CVE-2024-47736","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: handle overlapped pclusters out of crafted images properly\n\nsyzbot reported a task hang issue due to a deadlock case where it is\nwaiting for the folio lock of a …","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: handle overlapped pclusters out of crafted images properly\n\nsyzbot reported a task hang issue due to a deadlock case where it is\nwaiting for the folio lock of a …","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-667"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.13, < 6.10.13","linux_kernel >= 6.11, < 6.11.2"],"patched":["linux_kernel 6.11.2"],"published":"2024-10-21","updated":"2026-07-14","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2024-47736","references":[{"url":"https://git.kernel.org/stable/c/1bf7e414cac303c9aec1be67872e19be8b64980c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9cfa199bcbbbba31cbf97b2786f44f4464f3f29a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9e2f9d34dd12e6e5b244ec488bcebd0c2d566c50","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b9b30af0e86ffb485301ecd83b9129c9dfb7ebf8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c1172e65aad4b115392ea4c6e61e56e5b9b69df4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00182,"epssPercentile":0.08024,"ingestedAt":"2026-07-14T13:36:54.558Z","ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2024-10-21T12:59:50.164921Z"},"slug":"CVE-2024-47736","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nerofs: handle overlapped pclusters out of crafted images properly\n\nsyzbot reported a task hang issue due to a deadlock case where it is\nwaiting for the folio lock of a cached folio that will be used for\ncache I/Os.\n\nAfter looking into the crafted fuzzed image, I found it's formed with\nseveral overlapped big pclusters as below:\n\n Ext:   logical offset   |  length :     physical offset    |  length\n   0:        0..   16384 |   16384 :     151552..    167936 |   16384\n   1:    16384..   32768 |   16384 :     155648..    172032 |   16384\n   2:    32768..   49152 |   16384 :  537223168.. 537239552 |   16384\n...\n\nHere, extent 0/1 are physically overlapped although it's entirely\n_impossible_ for normal filesystem images generated by mkfs.\n\nFirst, managed folios containing compressed data will be marked as\nup-to-date and then unlocked immediately (unlike in-place folios) when\ncompressed I/Os are complete.  If physical blocks are not submitted in\nthe incremental order, there should be separate BIOs to avoid dependency\nissues.  However, the current code mis-arranges z_erofs_fill_bio_vec()\nand BIO submission which causes unexpected BIO waits.\n\nSecond, managed folios will be connected to their own pclusters for\nefficient inter-queries.  However, this is somewhat hard to implement\neasily if overlapped big pclusters exist.  Again, these only appear in\nfuzzed images so let's simply fall back to temporary short-lived pages\nfor correctness.\n\nAdditionally, it justifies that referenced managed folios cannot be\ntruncated for now and reverts part of commit 2080ca1ed3e4 (\"erofs: tidy\nup `struct z_erofs_bvec`\") for simplicity although it shouldn't be any\ndifference.\n\n## Affected\n\n- `linux_kernel >= 5.13, < 6.10.13`\n- `linux_kernel >= 6.11, < 6.11.2`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.11.2`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}