* [Qemu-devel] [PATCH] block/iscsi: avoid data corruption with cache=writeback
@ 2017-01-16 15:17 Peter Lieven
2017-01-17 11:28 ` [Qemu-devel] [Qemu-stable] " Fam Zheng
2017-01-20 16:45 ` [Qemu-devel] " Paolo Bonzini
0 siblings, 2 replies; 4+ messages in thread
From: Peter Lieven @ 2017-01-16 15:17 UTC (permalink / raw)
To: qemu-devel; +Cc: pbonzini, qemu-block, Peter Lieven, qemu-stable
nb_cls_shrunk in iscsi_allocmap_update can become -1 if the
request starts and ends within the same cluster. This results
in passing -1 to bitmap_set and bitmap_clear and they don't
handle negative values properly. In the end this leads to data
corruption.
Fixes: e1123a3b40a1a9a625a29c8ed4debb7e206ea690
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
---
block/iscsi.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/block/iscsi.c b/block/iscsi.c
index 6aeeb9e..1860f1b 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -499,14 +499,18 @@ iscsi_allocmap_update(IscsiLun *iscsilun, int64_t sector_num,
if (allocated) {
bitmap_set(iscsilun->allocmap, cl_num_expanded, nb_cls_expanded);
} else {
- bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
+ if (nb_cls_shrunk > 0) {
+ bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
+ }
}
if (iscsilun->allocmap_valid == NULL) {
return;
}
if (valid) {
- bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
+ if (nb_cls_shrunk > 0) {
+ bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
+ }
} else {
bitmap_clear(iscsilun->allocmap_valid, cl_num_expanded,
nb_cls_expanded);
--
1.9.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [Qemu-devel] [Qemu-stable] [PATCH] block/iscsi: avoid data corruption with cache=writeback
2017-01-16 15:17 [Qemu-devel] [PATCH] block/iscsi: avoid data corruption with cache=writeback Peter Lieven
@ 2017-01-17 11:28 ` Fam Zheng
2017-01-17 11:31 ` Peter Lieven
2017-01-20 16:45 ` [Qemu-devel] " Paolo Bonzini
1 sibling, 1 reply; 4+ messages in thread
From: Fam Zheng @ 2017-01-17 11:28 UTC (permalink / raw)
To: Peter Lieven; +Cc: qemu-devel, pbonzini, qemu-stable, qemu-block
On Mon, 01/16 16:17, Peter Lieven wrote:
> nb_cls_shrunk in iscsi_allocmap_update can become -1 if the
> request starts and ends within the same cluster. This results
> in passing -1 to bitmap_set and bitmap_clear and they don't
> handle negative values properly. In the end this leads to data
> corruption.
>
> Fixes: e1123a3b40a1a9a625a29c8ed4debb7e206ea690
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Peter Lieven <pl@kamp.de>
> ---
> block/iscsi.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/block/iscsi.c b/block/iscsi.c
> index 6aeeb9e..1860f1b 100644
> --- a/block/iscsi.c
> +++ b/block/iscsi.c
> @@ -499,14 +499,18 @@ iscsi_allocmap_update(IscsiLun *iscsilun, int64_t sector_num,
> if (allocated) {
> bitmap_set(iscsilun->allocmap, cl_num_expanded, nb_cls_expanded);
> } else {
> - bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
> + if (nb_cls_shrunk > 0) {
> + bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
> + }
> }
>
> if (iscsilun->allocmap_valid == NULL) {
> return;
> }
> if (valid) {
> - bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
> + if (nb_cls_shrunk > 0) {
> + bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
> + }
> } else {
> bitmap_clear(iscsilun->allocmap_valid, cl_num_expanded,
> nb_cls_expanded);
> --
> 1.9.1
>
>
It's probably a good idea to add assertions parameter in bitmap_*.
Reviewed-by: Fam Zheng <famz@redhat.com>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [Qemu-devel] [Qemu-stable] [PATCH] block/iscsi: avoid data corruption with cache=writeback
2017-01-17 11:28 ` [Qemu-devel] [Qemu-stable] " Fam Zheng
@ 2017-01-17 11:31 ` Peter Lieven
0 siblings, 0 replies; 4+ messages in thread
From: Peter Lieven @ 2017-01-17 11:31 UTC (permalink / raw)
To: Fam Zheng; +Cc: qemu-devel, pbonzini, qemu-stable, qemu-block
Am 17.01.2017 um 12:28 schrieb Fam Zheng:
> On Mon, 01/16 16:17, Peter Lieven wrote:
>> nb_cls_shrunk in iscsi_allocmap_update can become -1 if the
>> request starts and ends within the same cluster. This results
>> in passing -1 to bitmap_set and bitmap_clear and they don't
>> handle negative values properly. In the end this leads to data
>> corruption.
>>
>> Fixes: e1123a3b40a1a9a625a29c8ed4debb7e206ea690
>> Cc: qemu-stable@nongnu.org
>> Signed-off-by: Peter Lieven <pl@kamp.de>
>> ---
>> block/iscsi.c | 8 ++++++--
>> 1 file changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/block/iscsi.c b/block/iscsi.c
>> index 6aeeb9e..1860f1b 100644
>> --- a/block/iscsi.c
>> +++ b/block/iscsi.c
>> @@ -499,14 +499,18 @@ iscsi_allocmap_update(IscsiLun *iscsilun, int64_t sector_num,
>> if (allocated) {
>> bitmap_set(iscsilun->allocmap, cl_num_expanded, nb_cls_expanded);
>> } else {
>> - bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
>> + if (nb_cls_shrunk > 0) {
>> + bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
>> + }
>> }
>>
>> if (iscsilun->allocmap_valid == NULL) {
>> return;
>> }
>> if (valid) {
>> - bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
>> + if (nb_cls_shrunk > 0) {
>> + bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
>> + }
>> } else {
>> bitmap_clear(iscsilun->allocmap_valid, cl_num_expanded,
>> nb_cls_expanded);
>> --
>> 1.9.1
>>
>>
> It's probably a good idea to add assertions parameter in bitmap_*.
yes, i will send a follow-up patch.
Peter
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [Qemu-devel] [PATCH] block/iscsi: avoid data corruption with cache=writeback
2017-01-16 15:17 [Qemu-devel] [PATCH] block/iscsi: avoid data corruption with cache=writeback Peter Lieven
2017-01-17 11:28 ` [Qemu-devel] [Qemu-stable] " Fam Zheng
@ 2017-01-20 16:45 ` Paolo Bonzini
1 sibling, 0 replies; 4+ messages in thread
From: Paolo Bonzini @ 2017-01-20 16:45 UTC (permalink / raw)
To: Peter Lieven, qemu-devel; +Cc: qemu-stable, qemu-block
On 16/01/2017 16:17, Peter Lieven wrote:
> nb_cls_shrunk in iscsi_allocmap_update can become -1 if the
> request starts and ends within the same cluster. This results
> in passing -1 to bitmap_set and bitmap_clear and they don't
> handle negative values properly. In the end this leads to data
> corruption.
>
> Fixes: e1123a3b40a1a9a625a29c8ed4debb7e206ea690
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Peter Lieven <pl@kamp.de>
> ---
> block/iscsi.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
Queued, thanks.
Paolo
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2017-01-20 16:46 UTC | newest]
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2017-01-16 15:17 [Qemu-devel] [PATCH] block/iscsi: avoid data corruption with cache=writeback Peter Lieven
2017-01-17 11:28 ` [Qemu-devel] [Qemu-stable] " Fam Zheng
2017-01-17 11:31 ` Peter Lieven
2017-01-20 16:45 ` [Qemu-devel] " Paolo Bonzini
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