From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailout1.samsung.com ([203.254.224.24]:43925 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752854AbbL2Bxz (ORCPT ); Mon, 28 Dec 2015 20:53:55 -0500 From: Chao Yu To: 'Jaegeuk Kim' Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net References: <1451345497-65784-1-git-send-email-jaegeuk@kernel.org> In-reply-to: <1451345497-65784-1-git-send-email-jaegeuk@kernel.org> Subject: RE: [f2fs-dev] [PATCH 1/3] f2fs: early check broken symlink length in the encrypted case Date: Tue, 29 Dec 2015 09:52:49 +0800 Message-id: <00a701d141db$c2f7d480$48e77d80$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit Content-language: zh-cn Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Hi Jaegeuk, > -----Original Message----- > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org] > Sent: Tuesday, December 29, 2015 7:32 AM > To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org; > linux-f2fs-devel@lists.sourceforge.net > Cc: Jaegeuk Kim > Subject: [f2fs-dev] [PATCH 1/3] f2fs: early check broken symlink length in the encrypted case > > If link is broken, its len is zero, and we don't need to move forward. > > Signed-off-by: Jaegeuk Kim > --- > fs/f2fs/namei.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c > index fb41c80..5cc4128 100644 > --- a/fs/f2fs/namei.c > +++ b/fs/f2fs/namei.c > @@ -931,7 +931,7 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void > **cook > { > struct page *cpage = NULL; > char *caddr, *paddr = NULL; > - struct f2fs_str cstr; > + struct f2fs_str cstr = FSTR_INIT(NULL, 0); > struct f2fs_str pstr = FSTR_INIT(NULL, 0); > struct inode *inode = d_inode(dentry); > struct f2fs_encrypted_symlink_data *sd; > @@ -952,6 +952,12 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void > **cook > /* Symlink is encrypted */ > sd = (struct f2fs_encrypted_symlink_data *)caddr; > cstr.len = le16_to_cpu(sd->len); > + > + /* this is broken symlink case */ > + if (cstr.len == 0) { This case seems rare, can we add unlikely here? > + res = -ENOENT; > + goto errout; > + } > cstr.name = kmalloc(cstr.len, GFP_NOFS); > if (!cstr.name) { > res = -ENOMEM; > @@ -960,7 +966,7 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void > **cook > memcpy(cstr.name, sd->encrypted_path, cstr.len); > > /* this is broken symlink case */ > - if (cstr.name[0] == 0 && cstr.len == 0) { > + if (cstr.name[0] == 0) { ditto. Thanks, > res = -ENOENT; > goto errout; > } > -- > 2.5.4 (Apple Git-61) > > > ------------------------------------------------------------------------------ > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel