From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELsYTM8bZYc9bQFL7EwVguOu8VCQmyZQpQCPocvv+4wzFqzw2OGvLwQgfQOathv9Y9YsgX77 ARC-Seal: i=1; a=rsa-sha256; t=1520875753; cv=none; d=google.com; s=arc-20160816; b=YPRLou/D1tin0VLAbEKlUrOFQ64tHAu39mt4bomFuQNDCsT1kRhARbdrI9OI7F9Drt tBNplsd6s0PFz/cRg1rRpLt4kKOpEqlMWSlTps9YqVg0rzg+Y4PxR9PJyb/zoqMik+MY 3iiAH8FjNcvsZv8y4pIqxc4r/2yUb0c/dAKr5CcZOgafPJqCqZVk5yRcalyBPVtiUeLu Ciw1IuXVphGjmOS35RXflTkHIRnE8gmakq+QcQiUBLKU0cLCoPB1OQcolF6tYsziQFVX hiAK0twP2BGUX2rcaM/yEcf62K3Xo5dYegrPdZnckUsMFprAjRSkfXb69eRTJTWh3PWf dnAA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=message-id:date:subject:cc:to:from:dkim-signature:delivered-to :list-id:list-subscribe:list-unsubscribe:list-help:list-post :precedence:mailing-list:arc-authentication-results; bh=FLm1+b/vyyx7T0YppXiRuaSuDRaimGQ6Ze+jV6YYxww=; b=DYzhtErSk1wXIZJKUMyAhktO8XJ9Bdv39khC3Q7nM6g7AeDRIxLIawJXg+SjBdcDmz 3tR30grpazUsLIGfSA6nWcLYf/f17J29vxYBLnAULIssOBA4nvPl+CzHh0R4X1mxn8Fy +V6Zd6IuElaqI/4fZIR6dZUpBca9NBj8W/sPqta8BmEqo4VXZ7MFyvWk0/Zw/5yGPfaf Ig0kgcLZuWlBWaIL03MEeD9E6TfIW+9fh0xqoFQegrEMm6rw8RkJVitg3vWehHIiCKE6 NDVVB3t/iYTn0/3Dl+8dZkYjHSZU3jF3DAzqwGIYllkw3mFtm/RDwdeqzPXJLwhH3O/8 I78g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=trRpidUF; spf=pass (google.com: domain of kernel-hardening-return-12472-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12472-gregkh=linuxfoundation.org@lists.openwall.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=trRpidUF; spf=pass (google.com: domain of kernel-hardening-return-12472-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-12472-gregkh=linuxfoundation.org@lists.openwall.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm List-Post: List-Help: List-Unsubscribe: List-Subscribe: From: Salvatore Mesoraca To: linux-kernel@vger.kernel.org Cc: kernel-hardening@lists.openwall.com, linux-scsi@vger.kernel.org, "James E.J. Bottomley" , "Martin K. Petersen" , "Tobin C. Harding" , Dario Ballabio , Kees Cook , Salvatore Mesoraca , valdis.kletnieks@vt.edu Subject: [PATCH v3] scsi: eata: drop VLAs in reorder() Date: Mon, 12 Mar 2018 18:28:34 +0100 Message-Id: <1520875714-16903-1-git-send-email-s.mesoraca16@gmail.com> X-Mailer: git-send-email 1.9.1 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1594753814907865736?= X-GMAIL-MSGID: =?utf-8?q?1594753814907865736?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Avoid 3 VLAs[1] by using a single dinamically allocated array and some helper variables: we don't need 3 arrays. [1] https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Salvatore Mesoraca --- drivers/scsi/eata.c | 40 ++++++++++++++++++++++++++-------------- 1 file changed, 26 insertions(+), 14 deletions(-) diff --git a/drivers/scsi/eata.c b/drivers/scsi/eata.c index 6501c33..8ba44b7 100644 --- a/drivers/scsi/eata.c +++ b/drivers/scsi/eata.c @@ -2091,12 +2091,14 @@ static void sort(unsigned long sk[], unsigned int da[], unsigned int n, static int reorder(struct hostdata *ha, unsigned long cursec, unsigned int ihdlr, unsigned int il[], unsigned int n_ready) { + int overlap; struct scsi_cmnd *SCpnt; struct mscp *cpp; unsigned int k, n; unsigned int rev = 0, s = 1, r = 1; - unsigned int input_only = 1, overlap = 0; - unsigned long sl[n_ready], pl[n_ready], ll[n_ready]; + unsigned int input_only = 1; + unsigned long *sl; + unsigned long sl_zero, sl_cur, sl_prev, ll_cur, ll_prev; unsigned long maxsec = 0, minsec = ULONG_MAX, seek = 0, iseek = 0; unsigned long ioseek = 0; @@ -2115,6 +2117,12 @@ static int reorder(struct hostdata *ha, unsigned long cursec, if (n_ready <= 1) return 0; + overlap = -ENOMEM; + sl = kmalloc_array(n_ready, sizeof(*sl), GFP_ATOMIC); + if (!sl) + goto out; + overlap = 0; + for (n = 0; n < n_ready; n++) { k = il[n]; cpp = &ha->cp[k]; @@ -2164,31 +2172,33 @@ static int reorder(struct hostdata *ha, unsigned long cursec, if (!((rev && r) || (!rev && s))) sort(sl, il, n_ready, rev); + sl_zero = sl[0]; + if (!input_only) for (n = 0; n < n_ready; n++) { k = il[n]; cpp = &ha->cp[k]; SCpnt = cpp->SCpnt; - ll[n] = blk_rq_sectors(SCpnt->request); - pl[n] = SCpnt->serial_number; + ll_cur = blk_rq_sectors(SCpnt->request); + sl_cur = sl[n]; + sl[n] = SCpnt->serial_number; - if (!n) - continue; - - if ((sl[n] == sl[n - 1]) - || (!rev && ((sl[n - 1] + ll[n - 1]) > sl[n])) - || (rev && ((sl[n] + ll[n]) > sl[n - 1]))) + if (n && ((sl_cur == sl_prev) + || (!rev && ((sl_prev + ll_prev) > sl_cur)) + || (rev && ((sl_cur + ll_cur) > sl_prev)))) overlap = 1; + ll_prev = ll_cur; + sl_prev = sl_cur; } if (overlap) - sort(pl, il, n_ready, 0); + sort(sl, il, n_ready, 0); if (link_statistics) { - if (cursec > sl[0]) - iseek = cursec - sl[0]; + if (cursec > sl_zero) + iseek = cursec - sl_zero; else - iseek = sl[0] - cursec; + iseek = sl_zero - cursec; batchcount++; readycount += n_ready; seeknosort += seek / 1024; @@ -2225,6 +2235,8 @@ static int reorder(struct hostdata *ha, unsigned long cursec, YESNO(overlap), cpp->din); } #endif + kfree(sl); +out: return overlap; } -- 1.9.1