From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f44.google.com (mail-pj1-f44.google.com [209.85.216.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6CE4842385 for ; Mon, 18 Dec 2023 15:40:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pj1-f44.google.com with SMTP id 98e67ed59e1d1-28b4563a03aso810530a91.0 for ; Mon, 18 Dec 2023 07:40:39 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702914039; x=1703518839; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=qaVme4x1JzWucLWvJ+/IjgDKmL34flrE2DG+w6ZOMkg=; b=myGQIG+WumFILZmrmrE+x8go7CcYzp98BCn+wJ4/PnjZB5PT0PegZ7c/k5isWIpPgf mQLnhihcMPzFlUSx3zZdTRCR5sDWk3cDI186zCIKYtSI0Q9Khm/C0b0kc1loyiRjR643 2T4wmGhIkhHmlgD1QsFsp/Hke8RdcFeeDApZKrsDlbHon29FXHqOOuaEurJzSnVPe59e KLJtq+nYmP6Q0Ckqd9+ced5Cj0I/DmbVgLvMXdHC7zlu922EZs3R8miPtjapyxFPpGMU OmifUVCSeaOr7ygUjEDGNuYhmWMHoqqCG0/MbRVhw61QrldtO5LMs/zLUGEUoELgYPlW 5z1Q== X-Gm-Message-State: AOJu0YzRRu/PS8PljQhJQ/bsjIP+KxuKaxv3YPgV3K+HS3T1eW2X1UTT AShklYU9XFuMUBz7zLtepFA= X-Google-Smtp-Source: AGHT+IELv6NMMyA3Pd6MsFeOJg3I2acvaxvQXqnxeJPgp348jTEJz4tZaiWAcEgAY5bgJKTkcN/E9Q== X-Received: by 2002:a17:90a:4f05:b0:28b:9618:5f04 with SMTP id p5-20020a17090a4f0500b0028b96185f04mr633204pjh.20.1702914038278; Mon, 18 Dec 2023 07:40:38 -0800 (PST) Received: from localhost.localdomain ([110.14.71.32]) by smtp.gmail.com with ESMTPSA id fs7-20020a17090af28700b00286ed94466dsm5613041pjb.32.2023.12.18.07.40.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Dec 2023 07:40:37 -0800 (PST) From: Namjae Jeon To: gregkh@linuxfoundation.org, stable@vger.kernel.org Cc: smfrench@gmail.com, Namjae Jeon , Chih-Yen Chang , Steve French Subject: [PATCH 5.15.y 099/154] ksmbd: fix out-of-bound read in parse_lease_state() Date: Tue, 19 Dec 2023 00:33:59 +0900 Message-Id: <20231218153454.8090-100-linkinjeon@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231218153454.8090-1-linkinjeon@kernel.org> References: <20231218153454.8090-1-linkinjeon@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit [ Upstream commit fc6c6a3c324c1b3e93a03d0cfa3749c781f23de0 ] This bug is in parse_lease_state, and it is caused by the missing check of `struct create_context`. When the ksmbd traverses the create_contexts, it doesn't check if the field of `NameOffset` and `Next` is valid, The KASAN message is following: [ 6.664323] BUG: KASAN: slab-out-of-bounds in parse_lease_state+0x7d/0x280 [ 6.664738] Read of size 2 at addr ffff888005c08988 by task kworker/0:3/103 ... [ 6.666644] Call Trace: [ 6.666796] [ 6.666933] dump_stack_lvl+0x33/0x50 [ 6.667167] print_report+0xcc/0x620 [ 6.667903] kasan_report+0xae/0xe0 [ 6.668374] kasan_check_range+0x35/0x1b0 [ 6.668621] parse_lease_state+0x7d/0x280 [ 6.668868] smb2_open+0xbe8/0x4420 [ 6.675137] handle_ksmbd_work+0x282/0x820 Use smb2_find_context_vals() to find smb2 create request lease context. smb2_find_context_vals validate create context fields. Cc: stable@vger.kernel.org Reported-by: Chih-Yen Chang Tested-by: Chih-Yen Chang Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/ksmbd/oplock.c | 66 +++++++++++++++++------------------------------ 1 file changed, 24 insertions(+), 42 deletions(-) diff --git a/fs/ksmbd/oplock.c b/fs/ksmbd/oplock.c index 28c7f2193fb3..e2fb4631f8f7 100644 --- a/fs/ksmbd/oplock.c +++ b/fs/ksmbd/oplock.c @@ -1415,56 +1415,38 @@ void create_lease_buf(u8 *rbuf, struct lease *lease) */ struct lease_ctx_info *parse_lease_state(void *open_req) { - char *data_offset; struct create_context *cc; - unsigned int next = 0; - char *name; - bool found = false; struct smb2_create_req *req = (struct smb2_create_req *)open_req; - struct lease_ctx_info *lreq = kzalloc(sizeof(struct lease_ctx_info), - GFP_KERNEL); + struct lease_ctx_info *lreq; + + cc = smb2_find_context_vals(req, SMB2_CREATE_REQUEST_LEASE, 4); + if (IS_ERR_OR_NULL(cc)) + return NULL; + + lreq = kzalloc(sizeof(struct lease_ctx_info), GFP_KERNEL); if (!lreq) return NULL; - data_offset = (char *)req + le32_to_cpu(req->CreateContextsOffset); - cc = (struct create_context *)data_offset; - do { - cc = (struct create_context *)((char *)cc + next); - name = le16_to_cpu(cc->NameOffset) + (char *)cc; - if (le16_to_cpu(cc->NameLength) != 4 || - strncmp(name, SMB2_CREATE_REQUEST_LEASE, 4)) { - next = le32_to_cpu(cc->Next); - continue; - } - found = true; - break; - } while (next != 0); + if (sizeof(struct lease_context_v2) == le32_to_cpu(cc->DataLength)) { + struct create_lease_v2 *lc = (struct create_lease_v2 *)cc; - if (found) { - if (sizeof(struct lease_context_v2) == le32_to_cpu(cc->DataLength)) { - struct create_lease_v2 *lc = (struct create_lease_v2 *)cc; - - memcpy(lreq->lease_key, lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE); - lreq->req_state = lc->lcontext.LeaseState; - lreq->flags = lc->lcontext.LeaseFlags; - lreq->duration = lc->lcontext.LeaseDuration; - memcpy(lreq->parent_lease_key, lc->lcontext.ParentLeaseKey, - SMB2_LEASE_KEY_SIZE); - lreq->version = 2; - } else { - struct create_lease *lc = (struct create_lease *)cc; + memcpy(lreq->lease_key, lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE); + lreq->req_state = lc->lcontext.LeaseState; + lreq->flags = lc->lcontext.LeaseFlags; + lreq->duration = lc->lcontext.LeaseDuration; + memcpy(lreq->parent_lease_key, lc->lcontext.ParentLeaseKey, + SMB2_LEASE_KEY_SIZE); + lreq->version = 2; + } else { + struct create_lease *lc = (struct create_lease *)cc; - memcpy(lreq->lease_key, lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE); - lreq->req_state = lc->lcontext.LeaseState; - lreq->flags = lc->lcontext.LeaseFlags; - lreq->duration = lc->lcontext.LeaseDuration; - lreq->version = 1; - } - return lreq; + memcpy(lreq->lease_key, lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE); + lreq->req_state = lc->lcontext.LeaseState; + lreq->flags = lc->lcontext.LeaseFlags; + lreq->duration = lc->lcontext.LeaseDuration; + lreq->version = 1; } - - kfree(lreq); - return NULL; + return lreq; } /** -- 2.25.1