From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerin Jacob Subject: Re: [PATCH] bus/pci: fix driver name string manipulation Date: Tue, 15 May 2018 16:01:31 +0530 Message-ID: <20180515103130.GA14446@jerin> References: <20180515100335.13051-1-jerin.jacob@caviumnetworks.com> <54ecbab4-185e-2da6-8733-f40cc0648aa1@warmcat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: dev@dpdk.org, thomas@monjalon.net, ferruh.yigit@intel.com, Pablo de Lara To: Andy Green Return-path: Received: from NAM02-BL2-obe.outbound.protection.outlook.com (mail-bl2nam02on0064.outbound.protection.outlook.com [104.47.38.64]) by dpdk.org (Postfix) with ESMTP id CE5C22BC9 for ; Tue, 15 May 2018 12:31:51 +0200 (CEST) Content-Disposition: inline In-Reply-To: <54ecbab4-185e-2da6-8733-f40cc0648aa1@warmcat.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" -----Original Message----- > Date: Tue, 15 May 2018 18:19:19 +0800 > From: Andy Green > To: Jerin Jacob , dev@dpdk.org > CC: thomas@monjalon.net, ferruh.yigit@intel.com, Pablo de Lara > > Subject: Re: [dpdk-dev] [PATCH] bus/pci: fix driver name string manipulation > User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 > Thunderbird/52.7.0 > > > > On 05/15/2018 06:03 PM, Jerin Jacob wrote: > > sizeof(dri_name) is 8B on 64Bit systems.The intended operation is coping > > the string after '/' from the string `name`. > > > > This bug is not letting to probe any device string >8B hence results in > > the testpmd error("No ethernet devices found) on some PMDs. > > You are right... but... > > > Cc: Andy Green > > Cc: Pablo de Lara > > > > Fixes: fe5f777b538 ("bus/pci: replace strncpy by strlcpy") > > > > Signed-off-by: Jerin Jacob > > --- > > drivers/bus/pci/linux/pci.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c > > index a73ee49c2..cd45875b1 100644 > > --- a/drivers/bus/pci/linux/pci.c > > +++ b/drivers/bus/pci/linux/pci.c > > @@ -54,7 +54,7 @@ pci_get_kernel_driver_by_path(const char *filename, char *dri_name) > > name = strrchr(path, '/'); > > if (name) { > > - strlcpy(dri_name, name + 1, sizeof(dri_name)); > > + strlcpy(dri_name, name + 1, strlen(name)); > > ... this fix is no good. The underlying problem is the length of dri_name > is not getting passed into this function... it just doesn't know how much of > dri_name is safe to use. Telling it to use the strlen() of something > unrelated is going to make buffer overflows possible. In this case, already there is a check for following in the code. So it is fine either way. path[count] = '\0'; name = strrchr(path, '/'); > > I sent a patch to the list a few hours ago that amends this function to take > the allocated length of dri_name, and sets the limit for the strlcpy() to > that, so no matter what turns up in name it's not possible to blow past > dri_name allocation. > > [dpdk-dev] [PATCH] bus/pci: correct the earlier strlcpy conversion​ I am fine with taking any of the of the patch. Please improve the patch subject and bug description in case if you prefer to take your original patch. > > -Andy > > > return 0; > > } > >