Add both server & client side interfaces to create regular files in chroot environment
Signed-off-by: M. Mohan Kumar <mo...@in.ibm.com> --- hw/9pfs/virtio-9p-chroot-sv.c | 41 +++++++++++++++++++++++++++++++++++++++++ hw/9pfs/virtio-9p-local.c | 21 +++++++++++++++++++-- 2 files changed, 60 insertions(+), 2 deletions(-) diff --git a/hw/9pfs/virtio-9p-chroot-sv.c b/hw/9pfs/virtio-9p-chroot-sv.c index e9952b3..bab5f7c 100644 --- a/hw/9pfs/virtio-9p-chroot-sv.c +++ b/hw/9pfs/virtio-9p-chroot-sv.c @@ -85,6 +85,44 @@ static void chroot_do_open(V9fsFileObjectRequest *request, FdInfo *fd_info) } } +/* + * Helper routine to create a file and return the file descriptor and + * error status in FdInfo structure. + */ +static void chroot_do_create(V9fsFileObjectRequest *request, FdInfo *fd_info) +{ + uid_t cur_uid; + gid_t cur_gid; + + cur_uid = geteuid(); + cur_gid = getegid(); + + fd_info->fi_fd = -1; + + if (setfsuid(request->data.uid) < 0) { + fd_info->fi_error = errno; + return; + } + if (setfsgid(request->data.gid) < 0) { + fd_info->fi_error = errno; + goto unset_uid; + } + + fd_info->fi_fd = open(request->path.path, request->data.flags, + request->data.mode); + + if (fd_info->fi_fd < 0) { + fd_info->fi_error = errno; + } else { + fd_info->fi_error = 0; + fd_info->fi_flags = FI_FDVALID; + } + + setfsgid(cur_gid); +unset_uid: + setfsuid(cur_uid); +} + static int chroot_daemonize(int chroot_sock) { sigset_t sigset; @@ -185,6 +223,9 @@ int v9fs_chroot(FsContext *fs_ctx) case T_OPEN: chroot_do_open(&request, &fd_info); break; + case T_CREATE: + chroot_do_create(&request, &fd_info); + break; default: fd_info.fi_fd = 0; fd_info.fi_error = EIO; diff --git a/hw/9pfs/virtio-9p-local.c b/hw/9pfs/virtio-9p-local.c index bef0272..51911dd 100644 --- a/hw/9pfs/virtio-9p-local.c +++ b/hw/9pfs/virtio-9p-local.c @@ -53,6 +53,22 @@ static int passthrough_open(FsContext *fs_ctx, const char *path, int flags) return fd; } +static int passthrough_create(FsContext *fs_ctx, const char *path, int flags, + FsCred *credp) +{ + V9fsFileObjectRequest request; + int fd, error = 0; + + fill_request(&request, path, credp); + request.data.flags = flags; + request.data.type = T_CREATE; + fd = v9fs_request(fs_ctx, &request, &error); + if (fd < 0) { + errno = error; + } + return fd; +} + static int local_lstat(FsContext *fs_ctx, const char *path, struct stat *stbuf) { int err; @@ -377,8 +393,7 @@ static int local_open2(FsContext *fs_ctx, const char *path, int flags, serrno = errno; goto err_end; } - } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || - (fs_ctx->fs_sm == SM_NONE)) { + } else if (fs_ctx->fs_sm == SM_NONE) { fd = open(rpath(fs_ctx, path), flags, credp->fc_mode); if (fd == -1) { return fd; @@ -388,6 +403,8 @@ static int local_open2(FsContext *fs_ctx, const char *path, int flags, serrno = errno; goto err_end; } + } else if (fs_ctx->fs_sm == SM_PASSTHROUGH) { + fd = passthrough_create(fs_ctx, path, flags, credp); } return fd; -- 1.7.3.4