Commit d5941dd made the volume name configurable, but it didn't consider that the rw code compares the volume name string to assert that the first directory entry is the volume name. This made vvfat crash in rw mode.
This fixes the assertion to compare with the configured volume name instead of a literal string. Cc: qemu-sta...@nongnu.org Signed-off-by: Kevin Wolf <kw...@redhat.com> Reviewed-by: Markus Armbruster <arm...@redhat.com> Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com> --- block/vvfat.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/block/vvfat.c b/block/vvfat.c index 6b85314..ff3df35 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -2283,12 +2283,17 @@ DLOG(fprintf(stderr, "commit_direntries for %s, parent_mapping_index %d\n", mapp factor * (old_cluster_count - new_cluster_count)); for (c = first_cluster; !fat_eof(s, c); c = modified_fat_get(s, c)) { + direntry_t *first_direntry; void* direntry = array_get(&(s->directory), current_dir_index); int ret = vvfat_read(s->bs, cluster2sector(s, c), direntry, s->sectors_per_cluster); if (ret) return ret; - assert(!strncmp(s->directory.pointer, "QEMU", 4)); + + /* The first directory entry on the filesystem is the volume name */ + first_direntry = (direntry_t*) s->directory.pointer; + assert(!memcmp(first_direntry->name, s->volume_label, 11)); + current_dir_index += factor; } -- 1.8.3.1