From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 21661296BCC; Sun, 7 Jun 2026 10:53:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780829606; cv=none; b=r//wtHeE+R4Vf890cOwNPTRxQlTtIHnKzCf1UMVW6GQbuEXRcyUPaS7T8TlOI8QrO5oAHZttA/SR5b+fHHshZgd459na+Z6fgy/FMcfmeSWXvlPj9N7vgIGf2AcT04bzfqTKnTQlLRtAIo+v3SLChKInKN4MYFmFKSkNdUsmUkc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780829606; c=relaxed/simple; bh=uwweY3IP2xjT5lFbjnKVl6vuK3kGKcRE1L+kCBG/fVo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=k2QDt1oMxJQ47QSoGGEAVWhBtUYDJjrtne540nnuO0z+TnRdZV+O9dZJkav4I94zw6mUkkUBvf8adrzIXcsY8KWDY095L0qBZHYzjh5bDEK24kcWl4uPvDPZpkPphtdkO48bZMFMFWXn1Swyw2U11b+XXr2b58FYtwHlbjaLyMc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XmFpXYR2; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="XmFpXYR2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 268651F00893; Sun, 7 Jun 2026 10:53:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780829604; bh=zRvihZZzJe/in2qW9FaxXeLqvG2x8AtsDb3YCSizxHQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=XmFpXYR2D0wczWT39DYvXUC8Nx7jSOZSCS7/9a6eh4xM2PneUR/nocZYLRhgDCq6J ClofGkLS+ZY56WKJsTj8rKGF2txUQLoroGk1dgQto9C7K6KUkHm0dzMdDSDeDq/h4j 9cCvrwnIFgcHj+8uWdBO+1xywvr/vLZY9s+yFIIQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Michael Bommarito , Hannes Reinecke , "Martin K. Petersen" Subject: [PATCH 6.12 239/307] scsi: fcoe: Reject FIP descriptors with zero fip_dlen in CVL walker Date: Sun, 7 Jun 2026 12:00:36 +0200 Message-ID: <20260607095736.477535172@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260607095727.647295505@linuxfoundation.org> References: <20260607095727.647295505@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Bommarito commit 9eed1bd59937e6828b00d2f2dfef631d964f3636 upstream. drivers/scsi/fcoe/fcoe_ctlr.c::fcoe_ctlr_recv_clr_vlink() advanced the descriptor cursor by an attacker-supplied fip_dlen without ever requiring dlen >= sizeof(struct fip_desc) in the default branch. The named descriptor cases (FIP_DT_MAC, FIP_DT_NAME, FIP_DT_VN_ID) checked their per-type minimum lengths, but a FIP_DT_NON_CRITICAL descriptor (fip_dtype >= 128, which the standard requires receivers to silently ignore) skipped that check entirely. An unauthenticated L2 peer on the FCoE control VLAN could hang fcoe_ctlr_recv_work on an fcoe, qedf, or bnx2fc initiator indefinitely by emitting one FIP CVL frame whose single descriptor had fip_dtype == FIP_DT_NON_CRITICAL and fip_dlen == 0: the cursor advanced zero bytes per iteration and the loop condition rlen >= sizeof(*desc) stayed true forever, blocking every subsequent FIP frame on that controller. Tighten the outer dlen guard to also reject dlen < sizeof(struct fip_desc), so a malformed descriptor whose length cannot even cover the descriptor header is rejected before the switch. This is the same lower-bound the named cases already apply and is the minimum scope that closes the loop. Fixes: 97c8389d54b9 ("[SCSI] fcoe, libfcoe: Add support for FIP. FCoE discovery and keep-alive.") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito Reviewed-by: Hannes Reinecke Link: https://patch.msgid.link/20260518144307.2820961-1-michael.bommarito@gmail.com Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/fcoe/fcoe_ctlr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/scsi/fcoe/fcoe_ctlr.c +++ b/drivers/scsi/fcoe/fcoe_ctlr.c @@ -1386,7 +1386,7 @@ static void fcoe_ctlr_recv_clr_vlink(str while (rlen >= sizeof(*desc)) { dlen = desc->fip_dlen * FIP_BPW; - if (dlen > rlen) + if (dlen < sizeof(*desc) || dlen > rlen) goto err; /* Drop CVL if there are duplicate critical descriptors */ if ((desc->fip_dtype < 32) &&