Commit 066ae4f8 authored by Peter Maydell's avatar Peter Maydell
Browse files

Merge remote-tracking branch 'remotes/gkurz/tags/for-upstream' into staging 



Various bugfixes and code cleanups. Most notably, it fixes metadata handling in
mapped-file security mode (especially for the virtfs root).

# gpg: Signature made Tue 30 May 2017 14:36:22 BST
# gpg:                using DSA key 0x02FC3AEB0101DBC2
# gpg: Good signature from "Greg Kurz <groug@kaod.org>"
# gpg:                 aka "Greg Kurz <groug@free.fr>"
# gpg:                 aka "Greg Kurz <gkurz@linux.vnet.ibm.com>"
# gpg:                 aka "Gregory Kurz (Groug) <groug@free.fr>"
# gpg:                 aka "[jpeg image of size 3330]"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2BD4 3B44 535E C0A7 9894  DBA2 02FC 3AEB 0101 DBC2

* remotes/gkurz/tags/for-upstream:
  9pfs: local: metadata file for the VirtFS root
  9pfs: local: simplify file opening
  9pfs: local: resolve special directories in paths
  9pfs: check return value of v9fs_co_name_to_path()
  util: drop old utimensat() compat code
  9pfs: assume utimensat() and futimens() are present
  fsdev: fix virtfs-proxy-helper cwd
  9pfs: local: fix unlink of alien files in mapped-file mode
  9pfs: drop pdu_push_and_notify()
  fsdev: don't allow unknown format in marshal/unmarshal
  virtio-9p/xen-9p: move 9p specific bits to core 9p code

Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
parents 70f31414 81ffbf5a

configure

+0 −22
Original line number Diff line number Diff line
@@ -3629,25 +3629,6 @@ if compile_prog "" "" ; then 
  inotify1=yes

fi



# check if utimensat and futimens are supported

utimens=no

cat > $TMPC << EOF

#define _ATFILE_SOURCE

#include <stddef.h>

#include <fcntl.h>

#include <sys/stat.h>



int main(void)

{

    utimensat(AT_FDCWD, "foo", NULL, 0);

    futimens(0, NULL);

    return 0;

}

EOF

if compile_prog "" "" ; then

  utimens=yes

fi



# check if pipe2 is there

pipe2=no

cat > $TMPC << EOF
@@ -5434,9 +5415,6 @@ fi 
if test "$curses" = "yes" ; then

  echo "CONFIG_CURSES=y" >> $config_host_mak

fi

if test "$utimens" = "yes" ; then

  echo "CONFIG_UTIMENSAT=y" >> $config_host_mak

fi

if test "$pipe2" = "yes" ; then

  echo "CONFIG_PIPE2=y" >> $config_host_mak

fi

fsdev/9p-iov-marshal.c

+2 −2
Original line number Diff line number Diff line
@@ -168,7 +168,7 @@ ssize_t v9fs_iov_vunmarshal(struct iovec *out_sg, int out_num, size_t offset, 
            break;

        }

        default:

            break;

            g_assert_not_reached();

        }

        if (copied < 0) {

            return copied;
@@ -281,7 +281,7 @@ ssize_t v9fs_iov_vmarshal(struct iovec *in_sg, int in_num, size_t offset, 
            break;

        }

        default:

            break;

            g_assert_not_reached();

        }

        if (copied < 0) {

            return copied;

fsdev/virtfs-proxy-helper.c

+6 −5
Original line number Diff line number Diff line
@@ -945,7 +945,8 @@ static int process_requests(int sock) 
                                     &spec[0].tv_sec, &spec[0].tv_nsec,

                                     &spec[1].tv_sec, &spec[1].tv_nsec);

            if (retval > 0) {

                retval = qemu_utimens(path.data, spec);

                retval = utimensat(AT_FDCWD, path.data, spec,

                                   AT_SYMLINK_NOFOLLOW);

                if (retval < 0) {

                    retval = -errno;

                }
@@ -1129,14 +1130,14 @@ int main(int argc, char **argv) 
        }

    }



    if (chdir("/") < 0) {

        do_perror("chdir");

        goto error;

    }

    if (chroot(rpath) < 0) {

        do_perror("chroot");

        goto error;

    }

    if (chdir("/") < 0) {

        do_perror("chdir");

        goto error;

    }



    get_version = false;

#ifdef FS_IOC_GETVERSION

hw/9pfs/9p-handle.c

+0 −5
Original line number Diff line number Diff line
@@ -378,7 +378,6 @@ static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path, 
                            const struct timespec *buf)

{

    int ret;

#ifdef CONFIG_UTIMENSAT

    int fd;

    struct handle_data *data = (struct handle_data *)ctx->private;
@@ -388,10 +387,6 @@ static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path, 
    }

    ret = futimens(fd, buf);

    close(fd);

#else

    ret = -1;

    errno = ENOSYS;

#endif

    return ret;

}

hw/9pfs/9p-local.c

+128 −58
Original line number Diff line number Diff line
@@ -53,13 +53,37 @@ int local_open_nofollow(FsContext *fs_ctx, const char *path, int flags, 
                        mode_t mode)

{

    LocalData *data = fs_ctx->private;



    /* All paths are relative to the path data->mountfd points to */

    while (*path == '/') {

        path++;

    int fd = data->mountfd;



    while (*path && fd != -1) {

        const char *c;

        int next_fd;

        char *head;



        /* Only relative paths without consecutive slashes */

        assert(*path != '/');



        head = g_strdup(path);

        c = strchrnul(path, '/');

        if (*c) {

            /* Intermediate path element */

            head[c - path] = 0;

            path = c + 1;

            next_fd = openat_dir(fd, head);

        } else {

            /* Rightmost path element */

            next_fd = openat_file(fd, head, flags, mode);

            path = c;

        }

        g_free(head);

        if (fd != data->mountfd) {

            close_preserve_errno(fd);

        }

        fd = next_fd;

    }



    return relative_openat_nofollow(data->mountfd, path, flags, mode);

    assert(fd != data->mountfd);

    return fd;

}



int local_opendir_nofollow(FsContext *fs_ctx, const char *path)
@@ -83,6 +107,7 @@ static void unlinkat_preserve_errno(int dirfd, const char *path, int flags) 
}



#define VIRTFS_META_DIR ".virtfs_metadata"

#define VIRTFS_META_ROOT_FILE VIRTFS_META_DIR "_root"



static FILE *local_fopenat(int dirfd, const char *name, const char *mode)

{
@@ -119,6 +144,7 @@ static void local_mapped_file_attr(int dirfd, const char *name, 
    char buf[ATTR_MAX];

    int map_dirfd;



    if (strcmp(name, ".")) {

        map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);

        if (map_dirfd == -1) {

            return;
@@ -126,6 +152,9 @@ static void local_mapped_file_attr(int dirfd, const char *name, 


        fp = local_fopenat(map_dirfd, name, "r");

        close_preserve_errno(map_dirfd);

    } else {

        fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r");

    }

    if (!fp) {

        return;

    }
@@ -203,8 +232,19 @@ static int local_set_mapped_file_attrat(int dirfd, const char *name, 
    int ret;

    char buf[ATTR_MAX];

    int uid = -1, gid = -1, mode = -1, rdev = -1;

    int map_dirfd;

    int map_dirfd = -1, map_fd;

    bool is_root = !strcmp(name, ".");



    if (is_root) {

        fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r");

        if (!fp) {

            if (errno == ENOENT) {

                goto update_map_file;

            } else {

                return -1;

            }

        }

    } else {

        ret = mkdirat(dirfd, VIRTFS_META_DIR, 0700);

        if (ret < 0 && errno != EEXIST) {

            return -1;
@@ -224,6 +264,7 @@ static int local_set_mapped_file_attrat(int dirfd, const char *name, 
                return -1;

            }

        }

    }

    memset(buf, 0, ATTR_MAX);

    while (fgets(buf, ATTR_MAX, fp)) {

        if (!strncmp(buf, "virtfs.uid", 10)) {
@@ -240,12 +281,26 @@ static int local_set_mapped_file_attrat(int dirfd, const char *name, 
    fclose(fp);



update_map_file:

    if (is_root) {

        fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "w");

    } else {

        fp = local_fopenat(map_dirfd, name, "w");

        /* We can't go this far with map_dirfd not being a valid file descriptor

         * but some versions of gcc aren't smart enough to see it.

         */

        if (map_dirfd != -1) {

            close_preserve_errno(map_dirfd);

        }

    }

    if (!fp) {

        return -1;

    }



    map_fd = fileno(fp);

    assert(map_fd != -1);

    ret = fchmod(map_fd, 0600);

    assert(ret == 0);



    if (credp->fc_uid != -1) {

        uid = credp->fc_uid;

    }
@@ -454,7 +509,8 @@ static off_t local_telldir(FsContext *ctx, V9fsFidOpenState *fs) 


static bool local_is_mapped_file_metadata(FsContext *fs_ctx, const char *name)

{

    return !strcmp(name, VIRTFS_META_DIR);

    return

        !strcmp(name, VIRTFS_META_DIR) || !strcmp(name, VIRTFS_META_ROOT_FILE);

}



static struct dirent *local_readdir(FsContext *ctx, V9fsFidOpenState *fs)
@@ -471,7 +527,7 @@ again: 
        entry->d_type = DT_UNKNOWN;

    } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {

        if (local_is_mapped_file_metadata(ctx, entry->d_name)) {

            /* skip the meta data directory */

            /* skip the meta data */

            goto again;

        }

        entry->d_type = DT_UNKNOWN;
@@ -992,6 +1048,14 @@ static int local_unlinkat_common(FsContext *ctx, int dirfd, const char *name, 
    if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {

        int map_dirfd;



        /* We need to remove the metadata as well:

         * - the metadata directory if we're removing a directory

         * - the metadata file in the parent's metadata directory

         *

         * If any of these are missing (ie, ENOENT) then we're probably

         * trying to remove something that wasn't created in mapped-file

         * mode. We just ignore the error.

         */

        if (flags == AT_REMOVEDIR) {

            int fd;
@@ -999,32 +1063,20 @@ static int local_unlinkat_common(FsContext *ctx, int dirfd, const char *name, 
            if (fd == -1) {

                goto err_out;

            }

            /*

             * If directory remove .virtfs_metadata contained in the

             * directory

             */

            ret = unlinkat(fd, VIRTFS_META_DIR, AT_REMOVEDIR);

            close_preserve_errno(fd);

            if (ret < 0 && errno != ENOENT) {

                /*

                 * We didn't had the .virtfs_metadata file. May be file created

                 * in non-mapped mode ?. Ignore ENOENT.

                 */

                goto err_out;

            }

        }

        /*

         * Now remove the name from parent directory

         * .virtfs_metadata directory.

         */

        map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);

        if (map_dirfd != -1) {

            ret = unlinkat(map_dirfd, name, 0);

            close_preserve_errno(map_dirfd);

            if (ret < 0 && errno != ENOENT) {

            /*

             * We didn't had the .virtfs_metadata file. May be file created

             * in non-mapped mode ?. Ignore ENOENT.

             */

                goto err_out;

            }

        } else if (errno != ENOENT) {

            goto err_out;

        }

    }
@@ -1138,14 +1190,32 @@ static int local_name_to_path(FsContext *ctx, V9fsPath *dir_path, 
    }



    if (dir_path) {

        v9fs_path_sprintf(target, "%s/%s", dir_path->data, name);

    } else if (strcmp(name, "/")) {

        v9fs_path_sprintf(target, "%s", name);

        if (!strcmp(name, ".")) {

            /* "." relative to "foo/bar" is "foo/bar" */

            v9fs_path_copy(target, dir_path);

        } else if (!strcmp(name, "..")) {

            if (!strcmp(dir_path->data, ".")) {

                /* ".." relative to the root is "." */

                v9fs_path_sprintf(target, ".");

            } else {

        /* We want the path of the export root to be relative, otherwise

         * "*at()" syscalls would treat it as "/" in the host.

                char *tmp = g_path_get_dirname(dir_path->data);

                /* Symbolic links are resolved by the client. We can assume

                 * that ".." relative to "foo/bar" is equivalent to "foo"

                 */

        v9fs_path_sprintf(target, "%s", ".");

                v9fs_path_sprintf(target, "%s", tmp);

                g_free(tmp);

            }

        } else {

            assert(!strchr(name, '/'));

            v9fs_path_sprintf(target, "%s/%s", dir_path->data, name);

        }

    } else if (!strcmp(name, "/") || !strcmp(name, ".") ||

               !strcmp(name, "..")) {

            /* This is the root fid */

        v9fs_path_sprintf(target, ".");

    } else {

        assert(!strchr(name, '/'));

        v9fs_path_sprintf(target, "./%s", name);

    }

    return 0;

}