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GET /api/1.1/patches/2224783/?format=api
{ "id": 2224783, "url": "http://patchwork.ozlabs.org/api/1.1/patches/2224783/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-cifs-client/patch/20260418154505.84684-1-akif.sait111@gmail.com/", "project": { "id": 12, "url": "http://patchwork.ozlabs.org/api/1.1/projects/12/?format=api", "name": "Linux CIFS Client", "link_name": "linux-cifs-client", "list_id": "linux-cifs.vger.kernel.org", "list_email": "linux-cifs@vger.kernel.org", "web_url": "", "scm_url": "", "webscm_url": "" }, "msgid": "<20260418154505.84684-1-akif.sait111@gmail.com>", "date": "2026-04-18T15:45:05", "name": "ksmbd: fix O(N^2) DoS in smb2_lock via unbounded LockCount", "commit_ref": null, "pull_url": null, "state": "new", "archived": false, "hash": "5f2f01d61e09ab3d45be6d6618c612654bfd027f", "submitter": { "id": 93185, "url": "http://patchwork.ozlabs.org/api/1.1/people/93185/?format=api", "name": "Akif Sait", "email": "akif.sait111@gmail.com" }, "delegate": null, "mbox": "http://patchwork.ozlabs.org/project/linux-cifs-client/patch/20260418154505.84684-1-akif.sait111@gmail.com/mbox/", "series": [ { "id": 500450, "url": "http://patchwork.ozlabs.org/api/1.1/series/500450/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-cifs-client/list/?series=500450", "date": "2026-04-18T15:45:05", "name": "ksmbd: fix O(N^2) DoS in smb2_lock via unbounded LockCount", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/500450/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/patches/2224783/comments/", "check": "pending", "checks": "http://patchwork.ozlabs.org/api/patches/2224783/checks/", "tags": {}, "headers": { "Return-Path": "\n <linux-cifs+bounces-10898-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-cifs@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=f9cbbP1T;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c15:e001:75::12fc:5321; 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With no cap on\nLockCount a single authenticated request with LockCount=65535 results in\nroughly 2.1 billion iterations inside a ksmbd worker thread, pinning the\nCPU completely. A few concurrent requests hang the host entirely.\n\nCap lock_count at 64. The MS-SMB2 spec defines Open.LockSequenceArray\nas exactly 64 entries so 64 is the intended ceiling. No real workload\ncomes close to this in a single request.\n\nLet me know if you need more info or a reproducer.\n\nThanks,\nAkif\n\n\n fs/smb/server/smb2pdu.c | 2 +-\n 1 file changed, 1 insertion(+), 1 deletion(-)", "diff": "diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c\nindex ee32e61b6d3c..012f0c3585a0 100644\n--- a/fs/smb/server/smb2pdu.c\n+++ b/fs/smb/server/smb2pdu.c\n@@ -7492,7 +7492,7 @@ int smb2_lock(struct ksmbd_work *work)\n \tlock_ele = req->locks;\n \n \tksmbd_debug(SMB, \"lock count is %d\\n\", lock_count);\n-\tif (!lock_count) {\n+\tif (!lock_count || lock_count > 64) {\n \t\terr = -EINVAL;\n \t\tgoto out2;\n \t}\n", "prefixes": [] }