From: Kevin Wolf <kwolf@redhat.com>

Date: Thu, 29 Sep 2022 11:30:34 +0200

Subject: dmg: warn when opening dmg images containing blocks of unknown type

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Signed-off-by: Claudio Fontana <cfontana@suse.de>

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Message-Id: <20220929093035.4231-5-cfontana@suse.de>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

(cherry picked from commit 971974f0a9745a5163e1c825d38da03118054ae2)

Resolves: bsc#1208139

Signed-off-by: Dario Faggioli <dfaggioli@suse.com>

---

 block/dmg.c | 19 +++++++++++++++++++

 1 file changed, 19 insertions(+)

diff --git a/block/dmg.c b/block/dmg.c

index 837f18aa20ff7ebb35f961a9626c..96f8c2d14f004d0901d72d00b551 100644

--- a/block/dmg.c

+++ b/block/dmg.c

@@ -254,6 +254,25 @@ static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds,

     for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {

         s->types[i] = buff_read_uint32(buffer, offset);

         if (!dmg_is_known_block_type(s->types[i])) {

+            switch (s->types[i]) {

+            case UDBZ:

+                warn_report_once("dmg-bzip2 module is missing, accessing bzip2 "

+                                 "compressed blocks will result in I/O errors");

+                break;

+            case ULFO:

+                warn_report_once("dmg-lzfse module is missing, accessing lzfse "

+                                 "compressed blocks will result in I/O errors");

+                break;

+            case UDCM:

+            case UDLE:

+                /* Comments and last entry can be ignored without problems */

+                break;

+            default:

+                warn_report_once("Image contains chunks of unknown type %x, "

+                                 "accessing them will result in I/O errors",

+                                 s->types[i]);

+                break;

+            }

             chunk_count--;

             i--;

             offset += 40;