diff options
| -rw-r--r-- | src/basic/mountpoint-util.c | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/src/basic/mountpoint-util.c b/src/basic/mountpoint-util.c index 027e64c498..db36b2f2f6 100644 --- a/src/basic/mountpoint-util.c +++ b/src/basic/mountpoint-util.c @@ -94,7 +94,9 @@ int name_to_handle_at_loop( /* The buffer was too small. Size the new buffer by what name_to_handle_at() returned. */ n = h->handle_bytes; - if (offsetof(struct file_handle, f_handle) + n < n) /* check for addition overflow */ + + /* paranoia: check for overlow (note that .handle_bytes is unsigned only) */ + if (n > UINT_MAX - offsetof(struct file_handle, f_handle)) return -EOVERFLOW; } } @@ -213,9 +215,14 @@ int fd_is_mount_point(int fd, const char *filename, int flags) { * reported. Also, btrfs subvolumes have different st_dev, even though they aren't real mounts of * their own. */ - if (statx(fd, filename, (FLAGS_SET(flags, AT_SYMLINK_FOLLOW) ? 0 : AT_SYMLINK_NOFOLLOW) | - (flags & AT_EMPTY_PATH) | - AT_NO_AUTOMOUNT, STATX_TYPE, &sx) < 0) { + if (statx(fd, + filename, + (FLAGS_SET(flags, AT_SYMLINK_FOLLOW) ? 0 : AT_SYMLINK_NOFOLLOW) | + (flags & AT_EMPTY_PATH) | + AT_NO_AUTOMOUNT | /* don't trigger automounts – mounts are a local concept, hence no need to trigger automounts to determine STATX_ATTR_MOUNT_ROOT */ + AT_STATX_DONT_SYNC, /* don't go to the network for this – for similar reasons */ + STATX_TYPE, + &sx) < 0) { if (!ERRNO_IS_NOT_SUPPORTED(errno) && !ERRNO_IS_PRIVILEGE(errno)) return -errno; @@ -264,9 +271,9 @@ int fd_is_mount_point(int fd, const char *filename, int flags) { /* If the file handle for the directory we are interested in and its parent are identical, * we assume this is the root directory, which is a mount point. */ - if (h->handle_bytes == h_parent->handle_bytes && - h->handle_type == h_parent->handle_type && - memcmp(h->f_handle, h_parent->f_handle, h->handle_bytes) == 0) + if (h->handle_type == h_parent->handle_type && + memcmp_nn(h->f_handle, h->handle_bytes, + h_parent->f_handle, h_parent->handle_bytes) == 0) return 1; return mount_id != mount_id_parent; @@ -360,7 +367,9 @@ int path_get_mnt_id_at(int dir_fd, const char *path, int *ret) { if (statx(dir_fd, path, - AT_NO_AUTOMOUNT|(isempty(path) ? AT_EMPTY_PATH : AT_SYMLINK_NOFOLLOW), + (isempty(path) ? AT_EMPTY_PATH : AT_SYMLINK_NOFOLLOW) | + AT_NO_AUTOMOUNT | /* don't trigger automounts, mnt_id is a local concept */ + AT_STATX_DONT_SYNC, /* don't go to the network, mnt_id is a local concept */ STATX_MNT_ID, &buf.sx) < 0) { if (!ERRNO_IS_NOT_SUPPORTED(errno) && !ERRNO_IS_PRIVILEGE(errno)) |