| Message ID | 1451345497-65784-1-git-send-email-jaegeuk@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
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 <jaegeuk@kernel.org> > --- > 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 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Chao, On Tue, Dec 29, 2015 at 09:52:49AM +0800, Chao Yu wrote: > 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 <jaegeuk@kernel.org> > > --- > > 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? Agreed. Will change them. Thanks, > > > + 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 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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) { + 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) { res = -ENOENT; goto errout; }
If link is broken, its len is zero, and we don't need to move forward. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> --- fs/f2fs/namei.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)