Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter

2016-10-10 Thread Yan, Zheng

> On 10 Oct 2016, at 21:50, Ilya Dryomov  wrote:
> 
> On Mon, Oct 10, 2016 at 3:13 PM, Nikolay Borisov  wrote:
>> 
>> 
>> On 10/10/2016 04:11 PM, Yan, Zheng wrote:
>>> 
 On 10 Oct 2016, at 20:56, Nikolay Borisov  wrote:
 
 In case __ceph_do_getattr returns an error and the retry_op in
 ceph_read_iter is not READ_INLINE, then it's possible to invoke
 __free_page on a page which is NULL, this naturally leads to a crash.
 This can happen when, for example, a process waiting on a MDS reply
 receives sigterm.
 
 Fix this by explicitly checking whether the page is set or not.
 
 Signed-off-by: Nikolay Borisov 
 Link: http://www.spinics.net/lists/ceph-users/msg31592.html
 ---
 
 Inverted the condition, so resending with correct condition
 this time.
 
 fs/ceph/file.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
 
 diff --git a/fs/ceph/file.c b/fs/ceph/file.c
 index 3c68e6aee2f0..7413313ae6c8 100644
 --- a/fs/ceph/file.c
 +++ b/fs/ceph/file.c
 @@ -929,7 +929,8 @@ again:
 statret = __ceph_do_getattr(inode, page,
 CEPH_STAT_CAP_INLINE_DATA, !!page);
 if (statret < 0) {
 - __free_page(page);
 +if (page)
 +__free_page(page);
 if (statret == -ENODATA) {
 BUG_ON(retry_op != READ_INLINE);
 goto again;
 —
>>> Reviewed-by: Yan, Zheng 
>> 
>> I believe this needs to also be tagged as stable. To whomever is going
>> to merge it: can you please do that?
> 
> I'll do that.  Zheng, do you see any other issues with the killable
> wait here?

No.  this change is obvious, what’s your concern?

Regards
Yan, Zheng

> 
> Thanks,
> 
>Ilya



Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter

2016-10-10 Thread Ilya Dryomov
On Mon, Oct 10, 2016 at 3:13 PM, Nikolay Borisov  wrote:
>
>
> On 10/10/2016 04:11 PM, Yan, Zheng wrote:
>>
>>> On 10 Oct 2016, at 20:56, Nikolay Borisov  wrote:
>>>
>>> In case __ceph_do_getattr returns an error and the retry_op in
>>> ceph_read_iter is not READ_INLINE, then it's possible to invoke
>>> __free_page on a page which is NULL, this naturally leads to a crash.
>>> This can happen when, for example, a process waiting on a MDS reply
>>> receives sigterm.
>>>
>>> Fix this by explicitly checking whether the page is set or not.
>>>
>>> Signed-off-by: Nikolay Borisov 
>>> Link: http://www.spinics.net/lists/ceph-users/msg31592.html
>>> ---
>>>
>>> Inverted the condition, so resending with correct condition
>>> this time.
>>>
>>> fs/ceph/file.c | 3 ++-
>>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
>>> index 3c68e6aee2f0..7413313ae6c8 100644
>>> --- a/fs/ceph/file.c
>>> +++ b/fs/ceph/file.c
>>> @@ -929,7 +929,8 @@ again:
>>>  statret = __ceph_do_getattr(inode, page,
>>>  CEPH_STAT_CAP_INLINE_DATA, !!page);
>>>  if (statret < 0) {
>>> - __free_page(page);
>>> +if (page)
>>> +__free_page(page);
>>>  if (statret == -ENODATA) {
>>>  BUG_ON(retry_op != READ_INLINE);
>>>  goto again;
>>> —
>> Reviewed-by: Yan, Zheng 
>
> I believe this needs to also be tagged as stable. To whomever is going
> to merge it: can you please do that?

I'll do that.  Zheng, do you see any other issues with the killable
wait here?

Thanks,

Ilya


Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter

2016-10-10 Thread Nikolay Borisov


On 10/10/2016 04:11 PM, Yan, Zheng wrote:
> 
>> On 10 Oct 2016, at 20:56, Nikolay Borisov  wrote:
>>
>> In case __ceph_do_getattr returns an error and the retry_op in
>> ceph_read_iter is not READ_INLINE, then it's possible to invoke
>> __free_page on a page which is NULL, this naturally leads to a crash.
>> This can happen when, for example, a process waiting on a MDS reply
>> receives sigterm.
>>
>> Fix this by explicitly checking whether the page is set or not.
>>
>> Signed-off-by: Nikolay Borisov 
>> Link: http://www.spinics.net/lists/ceph-users/msg31592.html
>> ---
>>
>> Inverted the condition, so resending with correct condition
>> this time. 
>>
>> fs/ceph/file.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
>> index 3c68e6aee2f0..7413313ae6c8 100644
>> --- a/fs/ceph/file.c
>> +++ b/fs/ceph/file.c
>> @@ -929,7 +929,8 @@ again:
>>  statret = __ceph_do_getattr(inode, page,
>>  CEPH_STAT_CAP_INLINE_DATA, !!page);
>>  if (statret < 0) {
>> - __free_page(page);
>> +if (page)
>> +__free_page(page);
>>  if (statret == -ENODATA) {
>>  BUG_ON(retry_op != READ_INLINE);
>>  goto again;
>> — 
> Reviewed-by: Yan, Zheng 

I believe this needs to also be tagged as stable. To whomever is going
to merge it: can you please do that?


> 
>> 2.5.0
>>
> 


Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter

2016-10-10 Thread Yan, Zheng

> On 10 Oct 2016, at 21:13, Nikolay Borisov  wrote:
> 
> 
> 
> On 10/10/2016 04:11 PM, Yan, Zheng wrote:
>> 
>>> On 10 Oct 2016, at 20:56, Nikolay Borisov  wrote:
>>> 
>>> In case __ceph_do_getattr returns an error and the retry_op in
>>> ceph_read_iter is not READ_INLINE, then it's possible to invoke
>>> __free_page on a page which is NULL, this naturally leads to a crash.
>>> This can happen when, for example, a process waiting on a MDS reply
>>> receives sigterm.
>>> 
>>> Fix this by explicitly checking whether the page is set or not.
>>> 
>>> Signed-off-by: Nikolay Borisov 
>>> Link: http://www.spinics.net/lists/ceph-users/msg31592.html
>>> ---
>>> 
>>> Inverted the condition, so resending with correct condition
>>> this time. 
>>> 
>>> fs/ceph/file.c | 3 ++-
>>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>> 
>>> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
>>> index 3c68e6aee2f0..7413313ae6c8 100644
>>> --- a/fs/ceph/file.c
>>> +++ b/fs/ceph/file.c
>>> @@ -929,7 +929,8 @@ again:
>>> statret = __ceph_do_getattr(inode, page,
>>> CEPH_STAT_CAP_INLINE_DATA, !!page);
>>> if (statret < 0) {
>>> -__free_page(page);
>>> +   if (page)
>>> +   __free_page(page);
>>> if (statret == -ENODATA) {
>>> BUG_ON(retry_op != READ_INLINE);
>>> goto again;
>>> — 
>> Reviewed-by: Yan, Zheng 
> 
> I believe this needs to also be tagged as stable. To whomever is going
> to merge it: can you please do that?
> 

need to get it upstream first

> 
>> 
>>> 2.5.0
>>> 
>> 



Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter

2016-10-10 Thread Yan, Zheng

> On 10 Oct 2016, at 20:56, Nikolay Borisov  wrote:
> 
> In case __ceph_do_getattr returns an error and the retry_op in
> ceph_read_iter is not READ_INLINE, then it's possible to invoke
> __free_page on a page which is NULL, this naturally leads to a crash.
> This can happen when, for example, a process waiting on a MDS reply
> receives sigterm.
> 
> Fix this by explicitly checking whether the page is set or not.
> 
> Signed-off-by: Nikolay Borisov 
> Link: http://www.spinics.net/lists/ceph-users/msg31592.html
> ---
> 
> Inverted the condition, so resending with correct condition
> this time. 
> 
> fs/ceph/file.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
> index 3c68e6aee2f0..7413313ae6c8 100644
> --- a/fs/ceph/file.c
> +++ b/fs/ceph/file.c
> @@ -929,7 +929,8 @@ again:
>   statret = __ceph_do_getattr(inode, page,
>   CEPH_STAT_CAP_INLINE_DATA, !!page);
>   if (statret < 0) {
> -  __free_page(page);
> + if (page)
> + __free_page(page);
>   if (statret == -ENODATA) {
>   BUG_ON(retry_op != READ_INLINE);
>   goto again;
> — 
Reviewed-by: Yan, Zheng 

> 2.5.0
> 



[PATCHv2] ceph: Fix error handling in ceph_read_iter

2016-10-10 Thread Nikolay Borisov
In case __ceph_do_getattr returns an error and the retry_op in
ceph_read_iter is not READ_INLINE, then it's possible to invoke
__free_page on a page which is NULL, this naturally leads to a crash.
This can happen when, for example, a process waiting on a MDS reply
receives sigterm.

Fix this by explicitly checking whether the page is set or not.

Signed-off-by: Nikolay Borisov 
Link: http://www.spinics.net/lists/ceph-users/msg31592.html
---

Inverted the condition, so resending with correct condition
this time. 

 fs/ceph/file.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 3c68e6aee2f0..7413313ae6c8 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -929,7 +929,8 @@ again:
statret = __ceph_do_getattr(inode, page,
CEPH_STAT_CAP_INLINE_DATA, !!page);
if (statret < 0) {
-__free_page(page);
+   if (page)
+   __free_page(page);
if (statret == -ENODATA) {
BUG_ON(retry_op != READ_INLINE);
goto again;
-- 
2.5.0