From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZoAtSkIqsjHPRN87Qnk0QVO0WQT/fbJq1GfN0c7yMaVFVQN/R8NsUXZZqM7ctnr2t6HfGLq ARC-Seal: i=1; a=rsa-sha256; t=1525230344; cv=none; d=google.com; s=arc-20160816; b=TMLowlOgPu/TJNKtpzgsfiBjEjhdRzNp6IZxiWZ/Npj6s9I4Vqd9SSB3wecN1gosIm XF4+kkvfQS1NexqSTjSVdFtf+MQSMsSb9LshE9zqzwiboJX3n1+vUsVlH/Z/kcaPJEP8 Y2lRjDjOH7fL9UABdmvSkyHH0xQrxH3OuV1Ff7QRPdtF+Gtc+dvQBRP2HwBcce8RU4jh c+Vc2QyVP9XIidudj/mdjX2kVCXiwssLs/nDVgcgcAxO/J+nJIzC6jzz9zp3N5BUBfsZ b5DLAP16BwVepn58NWD4PtrmzHvlSP8cHk/1ij/JaOeNHhaiFb06ODGNvwNk1KHWOea2 EuIA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:message-id:in-reply-to:subject :cc:to:from:date:dkim-signature:arc-authentication-results; bh=me45gw7ITYDQFqNbTKg7UDDx+WxtdXn8rcibZTinnJg=; b=tXSY7W6rBmUlzx6EdMrpQmotnGE9gQoV+PgIOe6lHRM9ZsV2X9I8VdjDPWqHFWJ9ex OAi5CMJPCFBodM2skGatyQ+MizGnbiz1qZE00KSDfksHlI4Le8oWJHzQ8L6wlnW5RUel 1e+lUXvR4gkW8OTy7iy6R7LGqel6jo+IMBOe/+x2i/v4q8bKZbuKuhmHstN2n3kAyovK zI3xu6gpCzIzzCMYYDlRjB30EuVhFBG8Wd+tSKMd3ketnDHOu7+0AJzohkpWObhfd+9K yabgobTbCAERSK95GVdlorjKaZMBUNUnuV5FuMfjgQkTyFt135+88k/37ulv2BB7Dacc ytlA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=b4CifmJK; spf=pass (google.com: best guess record for domain of jsimmons@infradead.org designates 2001:8b0:10b:1236::1 as permitted sender) smtp.mailfrom=jsimmons@infradead.org Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=casper.20170209 header.b=b4CifmJK; spf=pass (google.com: best guess record for domain of jsimmons@infradead.org designates 2001:8b0:10b:1236::1 as permitted sender) smtp.mailfrom=jsimmons@infradead.org Date: Wed, 2 May 2018 04:05:39 +0100 (BST) From: James Simmons To: NeilBrown cc: Oleg Drokin , Greg Kroah-Hartman , Andreas Dilger , Linux Kernel Mailing List , Lustre Development List Subject: Re: [PATCH 10/10] staging: lustre: fix error deref in ll_splice_alias(). In-Reply-To: <152514675919.17843.11688659715084804936.stgit@noble> Message-ID: References: <152514658325.17843.11455067361317157487.stgit@noble> <152514675919.17843.11688659715084804936.stgit@noble> User-Agent: Alpine 2.21 (LFD 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180502_040540_021520_AA8D8C41 X-CRM114-Status: GOOD ( 16.13 ) X-Spam-Score: -0.0 (/) X-Spam-Report: SpamAssassin version 3.4.1 on casper.infradead.org summary: Content analysis details: (-0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 NO_RELAYS Informational: message was not relayed via SMTP X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1599232390798280014?= X-GMAIL-MSGID: =?utf-8?q?1599319932647535296?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: > d_splice_alias() can return an ERR_PTR(). > If it does while debugging is enabled, the following > CDEBUG() will dereference that error and crash. > > So add appropriate checking, and provide a separate > debug message for the error case. Yeah!!! It fixed the issues. Thank you. Reviewed-by: James Simmons > Reported-by: James Simmons > Fixes: e9d4f0b9f559 ("staging: lustre: llite: use d_splice_alias for directories.") > Signed-off-by: NeilBrown > --- > drivers/staging/lustre/lustre/llite/namei.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/lustre/lustre/llite/namei.c b/drivers/staging/lustre/lustre/llite/namei.c > index 6c9ec462eb41..24a6873d86a2 100644 > --- a/drivers/staging/lustre/lustre/llite/namei.c > +++ b/drivers/staging/lustre/lustre/llite/namei.c > @@ -442,11 +442,15 @@ struct dentry *ll_splice_alias(struct inode *inode, struct dentry *de) > } else { > struct dentry *new = d_splice_alias(inode, de); > > + if (IS_ERR(new)) > + CDEBUG(D_DENTRY, "splice inode %p as %pd gives error %lu\n", > + inode, de, PTR_ERR(new)); > if (new) > de = new; > } > - CDEBUG(D_DENTRY, "Add dentry %p inode %p refc %d flags %#x\n", > - de, d_inode(de), d_count(de), de->d_flags); > + if (!IS_ERR(de)) > + CDEBUG(D_DENTRY, "Add dentry %p inode %p refc %d flags %#x\n", > + de, d_inode(de), d_count(de), de->d_flags); > return de; > } > > > >