{"uuid": "3fa41ae0-9703-465b-985a-20c68e83d624", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "2a075640-a300-48a4-bb44-bc6130783b9b", "vulnerability": "CVE-2024-42256", "type": "seen", "source": "https://t.me/cvedetector/2767", "content": "{\n  \"Source\": \"CVE FEED\",\n  \"Title\": \"CVE-2024-42256 - \"CIFS Server Misaccounting Vulnerability\"\", \n  \"Content\": \"CVE ID : CVE-2024-42256 \nPublished : Aug. 8, 2024, 9:15 a.m. | 34\u00a0minutes ago \nDescription : In the Linux kernel, the following vulnerability has been resolved:  \n  \ncifs: Fix server re-repick on subrequest retry  \n  \nWhen a subrequest is marked for needing retry, netfs will call  \ncifs_prepare_write() which will make cifs repick the server for the op  \nbefore renegotiating credits; it then calls cifs_issue_write() which  \ninvokes smb2_async_writev() - which re-repicks the server.  \n  \nIf a different server is then selected, this causes the increment of  \nserver->in_flight to happen against one record and the decrement to happen  \nagainst another, leading to misaccounting.  \n  \nFix this by just removing the repick code in smb2_async_writev().  As this  \nis only called from netfslib-driven code, cifs_prepare_write() should  \nalways have been called first, and so server should never be NULL and the  \npreparatory step is repeated in the event that we do a retry.  \n  \nThe problem manifests as a warning looking something like:  \n  \n WARNING: CPU: 4 PID: 72896 at fs/smb/client/smb2ops.c:97 smb2_add_credits+0x3f0/0x9e0 [cifs]  \n ...  \n RIP: 0010:smb2_add_credits+0x3f0/0x9e0 [cifs]  \n ...  \n  smb2_writev_callback+0x334/0x560 [cifs]  \n  cifs_demultiplex_thread+0x77a/0x11b0 [cifs]  \n  kthread+0x187/0x1d0  \n  ret_from_fork+0x34/0x60  \n  ret_from_fork_asm+0x1a/0x30  \n  \nWhich may be triggered by a number of different xfstests running against an  \nAzure server in multichannel mode.  generic/249 seems the most repeatable,  \nbut generic/215, generic/249 and generic/308 may also show it. \nSeverity: 0.0 | NA \nVisit the link for more details, such as CVSS details, affected products, timeline, and more...\",\n  \"Detection Date\": \"08 Aug 2024\",\n  \"Type\": \"Vulnerability\"\n}\n\ud83d\udd39 t.me/cvedetector \ud83d\udd39", "creation_timestamp": "2024-08-08T12:12:57.000000Z"}