From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Layton Subject: [PATCH v5 19/19] vfs: make chroot retry once on ESTALE error Date: Wed, 8 Aug 2012 09:21:42 -0400 Message-ID: <1344432102-22312-20-git-send-email-jlayton@redhat.com> References: <1344432102-22312-1-git-send-email-jlayton@redhat.com> Cc: linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, michael.brantley@deshaw.com, hch@infradead.org, miklos@szeredi.hu, pstaubach@exagrid.com To: viro@ZenIV.linux.org.uk Return-path: In-Reply-To: <1344432102-22312-1-git-send-email-jlayton@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Signed-off-by: Jeff Layton --- fs/open.c | 43 +++++++++++++++++++++++++++---------------- 1 file changed, 27 insertions(+), 16 deletions(-) diff --git a/fs/open.c b/fs/open.c index 59a7e9d..991760f 100644 --- a/fs/open.c +++ b/fs/open.c @@ -455,27 +455,38 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename) { struct path path; int error; + int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY; + unsigned int try = 0; + char *name; - error = user_path_dir(filename, &path); - if (error) - goto out; + name = getname_flags(filename, lookup_flags, NULL); + if (IS_ERR(name)) + return PTR_ERR(name); - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); - if (error) - goto dput_and_out; + do { + error = kern_path_at(AT_FDCWD, name, lookup_flags, &path); + if (error) + break; - error = -EPERM; - if (!capable(CAP_SYS_CHROOT)) - goto dput_and_out; - error = security_path_chroot(&path); - if (error) - goto dput_and_out; + error = inode_permission(path.dentry->d_inode, + MAY_EXEC | MAY_CHDIR); + if (error) + goto dput_and_out; - set_fs_root(current->fs, &path); - error = 0; + error = -EPERM; + if (!capable(CAP_SYS_CHROOT)) + goto dput_and_out; + error = security_path_chroot(&path); + if (error) + goto dput_and_out; + + set_fs_root(current->fs, &path); + error = 0; dput_and_out: - path_put(&path); -out: + path_put(&path); + lookup_flags |= LOOKUP_REVAL; + } while (retry_estale(error, try++)); + putname(name); return error; } -- 1.7.11.2