Re: [Qemu-block] [PATCH v2 5/7] qcow2: Check snapshot L1 table in qcow2_snapshot_goto()

2018-03-07 Thread Eric Blake

On 03/06/2018 10:14 AM, Alberto Garcia wrote:

This function copies a snapshot's L1 table into the active one without
validating it first.

We now have a function to take care of this, so let's use it.

Signed-off-by: Alberto Garcia 
Cc: Eric Blake 
---
  block/qcow2-snapshot.c | 9 +
  tests/qemu-iotests/080 | 2 ++
  tests/qemu-iotests/080.out | 4 
  3 files changed, 15 insertions(+)



Reviewed-by: Eric Blake 

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.   +1-919-301-3266
Virtualization:  qemu.org | libvirt.org



[Qemu-block] [PATCH v2 5/7] qcow2: Check snapshot L1 table in qcow2_snapshot_goto()

2018-03-06 Thread Alberto Garcia
This function copies a snapshot's L1 table into the active one without
validating it first.

We now have a function to take care of this, so let's use it.

Signed-off-by: Alberto Garcia 
Cc: Eric Blake 
---
 block/qcow2-snapshot.c | 9 +
 tests/qemu-iotests/080 | 2 ++
 tests/qemu-iotests/080.out | 4 
 3 files changed, 15 insertions(+)

diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c
index bf94f4f434..0faf728dc4 100644
--- a/block/qcow2-snapshot.c
+++ b/block/qcow2-snapshot.c
@@ -465,6 +465,7 @@ int qcow2_snapshot_goto(BlockDriverState *bs, const char 
*snapshot_id)
 {
 BDRVQcow2State *s = bs->opaque;
 QCowSnapshot *sn;
+Error *local_err = NULL;
 int i, snapshot_index;
 int cur_l1_bytes, sn_l1_bytes;
 int ret;
@@ -477,6 +478,14 @@ int qcow2_snapshot_goto(BlockDriverState *bs, const char 
*snapshot_id)
 }
 sn = >snapshots[snapshot_index];
 
+ret = qcow2_validate_table(bs, sn->l1_table_offset, sn->l1_size,
+   sizeof(uint64_t), QCOW_MAX_L1_SIZE,
+   "Snapshot L1 table", _err);
+if (ret < 0) {
+error_report_err(local_err);
+goto fail;
+}
+
 if (sn->disk_size != bs->total_sectors * BDRV_SECTOR_SIZE) {
 error_report("qcow2: Loading snapshots with different disk "
 "size is not implemented");
diff --git a/tests/qemu-iotests/080 b/tests/qemu-iotests/080
index 018f815697..538857310f 100755
--- a/tests/qemu-iotests/080
+++ b/tests/qemu-iotests/080
@@ -180,6 +180,7 @@ poke_file "$TEST_IMG" "$offset_snap1_l1_offset" 
"\x00\x00\x00\x00\x00\x40\x02\x0
 { $QEMU_IMG amend -o compat=0.10 $TEST_IMG; } 2>&1 | _filter_testdir
 { $QEMU_IO -c "open -o overlap-check.inactive-l2=on $TEST_IMG" \
-c 'write 0 4k'; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IMG snapshot -a test $TEST_IMG; } 2>&1 | _filter_testdir
 
 echo
 echo "== Invalid snapshot L1 table size =="
@@ -191,6 +192,7 @@ poke_file "$TEST_IMG" "$offset_snap1_l1_size" 
"\x10\x00\x00\x00"
 { $QEMU_IMG amend -o compat=0.10 $TEST_IMG; } 2>&1 | _filter_testdir
 { $QEMU_IO -c "open -o overlap-check.inactive-l2=on $TEST_IMG" \
-c 'write 0 4k'; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IMG snapshot -a test $TEST_IMG; } 2>&1 | _filter_testdir
 
 # success, all done
 echo "*** done"
diff --git a/tests/qemu-iotests/080.out b/tests/qemu-iotests/080.out
index d622ac06c0..1525e1b087 100644
--- a/tests/qemu-iotests/080.out
+++ b/tests/qemu-iotests/080.out
@@ -68,6 +68,8 @@ qemu-img: Snapshot L1 table offset invalid
 qemu-img: Error while amending options: Invalid argument
 Failed to flush the refcount block cache: Invalid argument
 write failed: Invalid argument
+qemu-img: Snapshot L1 table offset invalid
+qemu-img: Could not apply snapshot 'test': Failed to load snapshot: Invalid 
argument
 
 == Invalid snapshot L1 table size ==
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
@@ -78,4 +80,6 @@ qemu-img: Snapshot L1 table too large
 qemu-img: Error while amending options: File too large
 Failed to flush the refcount block cache: File too large
 write failed: File too large
+qemu-img: Snapshot L1 table too large
+qemu-img: Could not apply snapshot 'test': Failed to load snapshot: File too 
large
 *** done
-- 
2.11.0