From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f41.google.com (mail-wm1-f41.google.com [209.85.128.41]) (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 B741723AE for ; Thu, 24 Nov 2022 10:20:38 +0000 (UTC) Received: by mail-wm1-f41.google.com with SMTP id 5so958389wmo.1 for ; Thu, 24 Nov 2022 02:20:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :from:to:cc:subject:date:message-id:reply-to; bh=rnU65IZVW7Ew6pXFCL1FtPt2utdOW4krxPUWMRLq6dI=; b=EgMvq8mHE7e9oJjxfwGGMI0X6RsU/hnpmrya0a46qA+IRz44kL+ygVKseMw8/tu+kf DrbXwSab0lsyvQKswhXK9kEI+f8Yq976XJcnaE2mLQ5o04rud4i9rmG5x0YaK+CtFA6Z uYSl3zKMTyIjQ1p7tiU1NHMqCHbKfOStQ/C0CimShiFhTItfIU5CrnCZoWkElSV7F4N/ hCx1YHbGHZvwycPG31H0Q5MX1Auvf7cou9SgYnu9dMyiiD1hPP4kWtO3eC6kGaB6E3X3 HfAsALjTF+NQjuVHCOtm5FlQ4WtwNFgIrXNZW2p91GOkQzUVhH0pe+uBCw7esVsEcrt3 ZFJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=rnU65IZVW7Ew6pXFCL1FtPt2utdOW4krxPUWMRLq6dI=; b=o8kk+O6T4Ia0aw41LZc4ipRJLlenQi3jl+RfLhmd1HoOgTPl29KQ8HFHcTEZNn5XW8 ZY4jFWh7jCCnryeIWYb/wvDXz7N/deY8shNVzjfn9Kfpapeq941/eaEBQu37ozsJld3k Hp1Vc3a0K1eawon02Z9iCHDuqZzcwujim1pk0P6i49juWC9VZBD+2IbYzWvg2XfoSVlI 4bY29PUdhPjvYsHneVZAa/NJ9kmnfYtgAu6+HbogTuGKWDrDKhvY974DbAaieSsX45FJ /Ntjv045W+OU06BZbAAPbEQB4ppMYgHg2WT3hwCPg6ZqErrkhsd7DUiTre2HiDyMIrBS XUug== X-Gm-Message-State: ANoB5pn2ES8TTKLC7W1+aZ6PEroF7dHEW5mcJ6+EY6ZvkVN/ekyCkylm yEBHJ6L/+bQxJ1ycBt/Rk3U= X-Google-Smtp-Source: AA0mqf7ia4WrQ4g+SdUZVhm18xb1EDYT2SKib81dQozI+h18g4Sgieac0ayfG6ouLIMxwe3cUPnzOw== X-Received: by 2002:a05:600c:3107:b0:3c6:e1b5:71c2 with SMTP id g7-20020a05600c310700b003c6e1b571c2mr9475161wmo.94.1669285236811; Thu, 24 Nov 2022 02:20:36 -0800 (PST) Received: from localhost ([102.36.222.112]) by smtp.gmail.com with ESMTPSA id y7-20020a1c4b07000000b003b4c979e6bcsm4940983wma.10.2022.11.24.02.20.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Nov 2022 02:20:36 -0800 (PST) Date: Thu, 24 Nov 2022 13:20:30 +0300 From: Dan Carpenter To: dan.j.williams@intel.com Cc: nvdimm@lists.linux.dev Subject: [bug report] libnvdimm: fix mishandled nvdimm_clear_poison() return value Message-ID: Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hello Dan Williams, The patch 868f036fee4b: "libnvdimm: fix mishandled nvdimm_clear_poison() return value" from Dec 16, 2016, leads to the following Smatch static checker warnings: drivers/nvdimm/claim.c:287 nsio_rw_bytes() warn: replace divide condition 'cleared / 512' with 'cleared >= 512' drivers/nvdimm/bus.c:210 nvdimm_account_cleared_poison() warn: replace divide condition 'cleared / 512' with 'cleared >= 512' drivers/nvdimm/claim.c 252 static int nsio_rw_bytes(struct nd_namespace_common *ndns, 253 resource_size_t offset, void *buf, size_t size, int rw, 254 unsigned long flags) 255 { 256 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 257 unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512); 258 sector_t sector = offset >> 9; 259 int rc = 0, ret = 0; 260 261 if (unlikely(!size)) 262 return 0; 263 264 if (unlikely(offset + size > nsio->size)) { 265 dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n"); 266 return -EFAULT; 267 } 268 269 if (rw == READ) { 270 if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) 271 return -EIO; 272 if (copy_mc_to_kernel(buf, nsio->addr + offset, size) != 0) 273 return -EIO; 274 return 0; 275 } 276 277 if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) { 278 if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512) 279 && !(flags & NVDIMM_IO_ATOMIC)) { 280 long cleared; 281 282 might_sleep(); 283 cleared = nvdimm_clear_poison(&ndns->dev, 284 nsio->res.start + offset, size); 285 if (cleared < size) 286 rc = -EIO; --> 287 if (cleared > 0 && cleared / 512) { ^^^^^^^^^^^^^ Smatch suggests changing this to "&& cleared >= 512" but it doesn't make sense to say if (cleared > 0 && cleared >= 512) {. Probably what was instead intended was "if (cleared > 0 && (cleared % 512) == 0) {"? 288 cleared /= 512; 289 badblocks_clear(&nsio->bb, sector, cleared); 290 } 291 arch_invalidate_pmem(nsio->addr + offset, size); 292 } else 293 rc = -EIO; 294 } 295 296 memcpy_flushcache(nsio->addr + offset, buf, size); 297 ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL); 298 if (ret) 299 rc = ret; 300 301 return rc; 302 } regards, dan carpenter