OpenE2K/qemu-e2k
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qemu-e2k/block
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Maxim Levitsky c8bf9a9169 qcow2: Fix corruption on write_zeroes with MAY_UNMAP 
Commit 205fa50750 ("qcow2: Add subcluster support to zero_in_l2_slice()")
introduced a subtle change to code in zero_in_l2_slice:

It swapped the order of

1. qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_slice);
2. set_l2_entry(s, l2_slice, l2_index + i, QCOW_OFLAG_ZERO);
3. qcow2_free_any_clusters(bs, old_offset, 1, QCOW2_DISCARD_REQUEST);

To

1. qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_slice);
2. qcow2_free_any_clusters(bs, old_offset, 1, QCOW2_DISCARD_REQUEST);
3. set_l2_entry(s, l2_slice, l2_index + i, QCOW_OFLAG_ZERO);

It seems harmless, however the call to qcow2_free_any_clusters can
trigger a cache flush which can mark the L2 table as clean, and
assuming that this was the last write to it, a stale version of it
will remain on the disk.

Now we have a valid L2 entry pointing to a freed cluster. Oops.

Fixes: 205fa50750 ("qcow2: Add subcluster support to zero_in_l2_slice()")
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
[ kwolf: Fixed to restore the correct original order from before
  205fa50750; added comments like in discard_in_l2_slice(). ]
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201124092815.39056-1-kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-11-24 11:29:41 +01:00
..
export meson: move vhost_user_blk_server to meson.build 2020-11-12 09:19:40 -05:00
monitor block/export: Add block-export-del 2020-10-02 15:46:40 +02:00
accounting.c
aio_task.c
amend.c block/amend: Check whether the node exists 2020-07-27 12:37:25 +02:00
backup-top.c block: Inline bdrv_co_block_status_from_*() 2020-09-07 12:31:31 +02:00
backup-top.h
backup.c backup: Deal with filters 2020-09-07 12:31:31 +02:00
blkdebug.c block: Fix some code style problems, "foo* bar" should be "foo *bar" 2020-11-09 18:42:47 +01:00
blklogwrites.c block: Inline bdrv_co_block_status_from_*() 2020-09-07 12:31:31 +02:00
blkreplay.c block: Use bdrv_default_perms() 2020-05-18 19:05:25 +02:00
blkverify.c error: Eliminate error_propagate() with Coccinelle, part 2 2020-07-10 15:18:08 +02:00
block-backend.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
block-copy.c block-copy: Use CAF to find sync=top base 2020-09-07 12:31:31 +02:00
block-gen.h scripts: add block-coroutine-wrapper.py 2020-10-05 10:59:06 +01:00
bochs.c block: Use bdrv_default_perms() 2020-05-18 19:05:25 +02:00
cloop.c block: Use bdrv_default_perms() 2020-05-18 19:05:25 +02:00
commit.c block: Return depth level during bdrv_is_allocated_above 2020-10-30 15:21:23 -05:00
copy-on-read.c block: Inline bdrv_co_block_status_from_*() 2020-09-07 12:31:31 +02:00
coroutines.h block: Return depth level during bdrv_is_allocated_above 2020-10-30 15:21:23 -05:00
create.c
crypto.c nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
crypto.h nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
curl.c error: Eliminate error_propagate() with Coccinelle, part 1 2020-07-10 15:18:08 +02:00
dirty-bitmap.c block/dirty-bitmap: add bdrv_has_named_bitmaps helper 2020-05-28 13:15:22 -05:00
dmg-bz2.c
dmg-lzfse.c block: Remove unused include 2020-11-09 15:44:21 +01:00
dmg.c block: Fix some code style problems, "foo* bar" should be "foo *bar" 2020-11-09 18:42:47 +01:00
dmg.h
file-posix.c file-posix: allow -EBUSY errors during write zeros on raw block devices 2020-11-17 12:26:48 +01:00
file-win32.c block/file: switch to use qemu_open/qemu_create for improved errors 2020-09-16 10:33:48 +01:00
filter-compress.c block: Inline bdrv_co_block_status_from_*() 2020-09-07 12:31:31 +02:00
gluster.c error: Reduce unnecessary error propagation 2020-07-10 15:18:08 +02:00
io_uring.c io_uring: do not use pointer after free 2020-11-17 12:26:48 +01:00
io.c block: Return depth level during bdrv_is_allocated_above 2020-10-30 15:21:23 -05:00
iscsi-opts.c
iscsi.c qapi: Restrict query-uuid command to machine code 2020-09-29 15:41:35 +02:00
linux-aio.c misc: Replace zero-length arrays with flexible array member (automatic) 2020-03-16 22:07:42 +01:00
meson.build block/export: convert vhost-user-blk server to block export API 2020-10-23 13:42:16 +01:00
mirror.c block: Return depth level during bdrv_is_allocated_above 2020-10-30 15:21:23 -05:00
nbd.c nbd: Add 'qemu-nbd -A' to expose allocation depth 2020-10-30 15:22:00 -05:00
nfs.c block: Fixes nfs compiling error on msys2/mingw 2020-11-09 15:44:21 +01:00
null.c block/null: Implement bdrv_get_allocated_file_size 2020-09-07 12:31:31 +02:00
nvme.c block/nvme: Fix nvme_submit_command() on big-endian host 2020-11-03 19:06:22 +00:00
parallels.c error: Avoid error_propagate() after migrate_add_blocker() 2020-07-10 15:18:08 +02:00
parallels.h
qapi-sysemu.c block: Move system emulator QMP commands to block/qapi-sysemu.c 2020-03-06 17:15:38 +01:00
qapi.c migration: introduce icount field for snapshots 2020-10-06 08:34:49 +02:00
qcow2-bitmap.c qcow2: Use macros for the L1, refcount and bitmap table entry sizes 2020-09-15 11:05:12 +02:00
qcow2-cache.c
qcow2-cluster.c qcow2: Fix corruption on write_zeroes with MAY_UNMAP 2020-11-24 11:29:41 +01:00
qcow2-refcount.c qcow2: Make qcow2_free_any_clusters() free only one cluster 2020-09-15 11:05:13 +02:00
qcow2-snapshot.c migration: introduce icount field for snapshots 2020-10-06 08:34:49 +02:00
qcow2-threads.c qcow2: add zstd cluster compression 2020-05-13 14:20:31 +02:00
qcow2.c block: Fix some code style problems, "foo* bar" should be "foo *bar" 2020-11-09 18:42:47 +01:00
qcow2.h block: Fix some code style problems, "foo* bar" should be "foo *bar" 2020-11-09 18:42:47 +01:00
qcow.c block/qcow: remove runtime opts 2020-09-15 11:05:13 +02:00
qed-check.c
qed-cluster.c
qed-l2-cache.c
qed-table.c
qed.c qapi: Smooth another visitor error checking pattern 2020-07-10 15:18:08 +02:00
qed.h qed: Simplify backing reads 2020-07-06 10:34:14 +02:00
quorum.c quorum: Require WRITE perm with rewrite-corrupted 2020-11-17 12:38:28 +01:00
raw-format.c error: Eliminate error_propagate() with Coccinelle, part 2 2020-07-10 15:18:08 +02:00
rbd.c block/rbd: add 'namespace' to qemu_rbd_strong_runtime_opts[] 2020-09-15 11:31:10 +02:00
replication.c error: Reduce unnecessary error propagation 2020-07-10 15:18:08 +02:00
sheepdog.c block: deprecate the sheepdog block driver 2020-10-15 16:06:28 +02:00
snapshot.c block/snapshot: Fix fallback 2020-09-07 12:31:31 +02:00
ssh.c qapi: Smooth another visitor error checking pattern 2020-07-10 15:18:08 +02:00
stream.c block: Return depth level during bdrv_is_allocated_above 2020-10-30 15:21:23 -05:00
throttle-groups.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
throttle.c qemu/atomic.h: rename atomic_ to qatomic_ 2020-09-23 16:07:44 +01:00
trace-events block/nvme: Use unsigned integer for queue counter/size 2020-11-03 19:06:21 +00:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
vdi.c error: Avoid error_propagate() after migrate_add_blocker() 2020-07-10 15:18:08 +02:00
vhdx-endian.c
vhdx-log.c block: Add flags to bdrv(_co)_truncate() 2020-04-30 17:51:07 +02:00
vhdx.c block/vhdx: Support vhdx image only with 512 bytes logical sector size 2020-09-15 11:05:13 +02:00
vhdx.h
vmdk.c vmdk: fix maybe uninitialized warnings 2020-10-13 13:33:45 +02:00
vpc.c block: Fix some code style problems, "foo* bar" should be "foo *bar" 2020-11-09 18:42:47 +01:00
vvfat.c block/vvfat: Fix bad printf format specifiers 2020-11-03 16:24:56 +01:00
win32-aio.c
write-threshold.c