[v9,0/7] Introduce sendpage_ok() to detect misused sendpage in network related drivers

Message

Coly Li Oct. 1, 2020, 7:54 a.m. UTC

This series was original by a bug fix in nvme-over-tcp driver which only
checked whether a page was allocated from slab allcoator, but forgot to
check its page_count: The page handled by sendpage should be neither a
Slab page nor 0 page_count page.

As Sagi Grimberg suggested, the original fix is refind to a more common
inline routine:
    static inline bool sendpage_ok(struct page *page)
    {
        return  (!PageSlab(page) && page_count(page) >= 1);
    }
If sendpage_ok() returns true, the checking page can be handled by the
concrete zero-copy sendpage method in network layer.

The v9 series has 7 patches, no change from v8 series,
- The 1st patch in this series introduces sendpage_ok() in header file
  include/linux/net.h.
- The 2nd patch adds WARN_ONCE() for improper zero-copy send in
  kernel_sendpage().
- The 3rd patch fixes the page checking issue in nvme-over-tcp driver.
- The 4th patch adds page_count check by using sendpage_ok() in
  do_tcp_sendpages() as Eric Dumazet suggested.
- The 5th and 6th patches just replace existing open coded checks with
  the inline sendpage_ok() routine.

Coly Li

Cc: Chaitanya Kulkarni <[e-mail]>
Cc: Chris Leech <[e-mail]>
Cc: Christoph Hellwig <[e-mail]>
Cc: Cong Wang <[e-mail]>
Cc: David S. Miller <[e-mail]>
Cc: Eric Dumazet <[e-mail]>
Cc: Hannes Reinecke <[e-mail]>
Cc: Ilya Dryomov <[e-mail]>
Cc: Jan Kara <[e-mail]>
Cc: Jeff Layton <[e-mail]>
Cc: Jens Axboe <[e-mail]>
Cc: Lee Duncan <[e-mail]>
Cc: Mike Christie <[e-mail]>
Cc: Mikhail Skorzhinskii <[e-mail]>
Cc: Philipp Reisner <[e-mail]>
Cc: Sagi Grimberg <[e-mail]>
Cc: Vasily Averin <[e-mail]>
Cc: Vlastimil Babka <[e-mail]>
---
Changelog:
v9, fix a typo pointed out by Greg KH.
    add Acked-by tags from Martin K. Petersen and Ilya Dryomov.
v8: add WARN_ONCE() in kernel_sendpage() as Christoph suggested.
v7: remove outer brackets from the return line of sendpage_ok() as
    Eric Dumazet suggested.
v6: fix page check in do_tcp_sendpages(), as Eric Dumazet suggested.
    replace other open coded checks with sendpage_ok() in libceph,
    iscsi drivers.
v5, include linux/mm.h in include/linux/net.h
v4, change sendpage_ok() as an inline helper, and post it as
    separate patch, as Christoph Hellwig suggested.
v3, introduce a more common sendpage_ok() as Sagi Grimberg suggested.
v2, fix typo in patch subject
v1, the initial version.


Coly Li (7):
  net: introduce helper sendpage_ok() in include/linux/net.h
  net: add WARN_ONCE in kernel_sendpage() for improper zero-copy send
  nvme-tcp: check page by sendpage_ok() before calling kernel_sendpage()
  tcp: use sendpage_ok() to detect misused .sendpage
  drbd: code cleanup by using sendpage_ok() to check page for
    kernel_sendpage()
  scsi: libiscsi: use sendpage_ok() in iscsi_tcp_segment_map()
  libceph: use sendpage_ok() in ceph_tcp_sendpage()

 drivers/block/drbd/drbd_main.c |  2 +-
 drivers/nvme/host/tcp.c        |  7 +++----
 drivers/scsi/libiscsi_tcp.c    |  2 +-
 include/linux/net.h            | 16 ++++++++++++++++
 net/ceph/messenger.c           |  2 +-
 net/ipv4/tcp.c                 |  3 ++-
 net/socket.c                   |  6 ++++--
 7 files changed, 28 insertions(+), 10 deletions(-)

Comments

David Miller Oct. 1, 2020, 7:43 p.m. UTC | #1

From: Coly Li <[e-mail]>
Date: Thu,  1 Oct 2020 15:54:01 +0800

> This series was original by a bug fix in nvme-over-tcp driver which only
> checked whether a page was allocated from slab allcoator, but forgot to
> check its page_count: The page handled by sendpage should be neither a
> Slab page nor 0 page_count page.
> 
> As Sagi Grimberg suggested, the original fix is refind to a more common
> inline routine:
>     static inline bool sendpage_ok(struct page *page)
>     {
>         return  (!PageSlab(page) && page_count(page) >= 1);
>     }
> If sendpage_ok() returns true, the checking page can be handled by the
> concrete zero-copy sendpage method in network layer.
> 
> The v9 series has 7 patches, no change from v8 series,
> - The 1st patch in this series introduces sendpage_ok() in header file
>   include/linux/net.h.
> - The 2nd patch adds WARN_ONCE() for improper zero-copy send in
>   kernel_sendpage().
> - The 3rd patch fixes the page checking issue in nvme-over-tcp driver.
> - The 4th patch adds page_count check by using sendpage_ok() in
>   do_tcp_sendpages() as Eric Dumazet suggested.
> - The 5th and 6th patches just replace existing open coded checks with
 ...

Series applied and queued up for -stable, thank you.

David Miller Oct. 1, 2020, 7:48 p.m. UTC | #2

From: David Miller <[e-mail]>
Date: Thu, 01 Oct 2020 12:43:45 -0700 (PDT)

> Series applied and queued up for -stable, thank you.

Actually, this doesn't even build:

In file included from ./arch/x86/include/asm/bug.h:93,
                 from ./include/linux/bug.h:5,
                 from ./include/linux/mmdebug.h:5,
                 from ./include/linux/mm.h:9,
                 from net/socket.c:55:
net/socket.c: In function ‘kernel_sendpage’:
./include/asm-generic/bug.h:97:3: error: too few arguments to function ‘__warn_printk’
   97 |   __warn_printk(arg);     \
      |   ^~~~~~~~~~~~~

Was this even build tested?

Coly Li Oct. 2, 2020, 8:30 a.m. UTC | #3

On 2020/10/2 03:48, David Miller wrote:
> From: David Miller <[e-mail]>
> Date: Thu, 01 Oct 2020 12:43:45 -0700 (PDT)
> 
>> Series applied and queued up for -stable, thank you.
> 
> Actually, this doesn't even build:
> 
> In file included from ./arch/x86/include/asm/bug.h:93,
>                  from ./include/linux/bug.h:5,
>                  from ./include/linux/mmdebug.h:5,
>                  from ./include/linux/mm.h:9,
>                  from net/socket.c:55:
> net/socket.c: In function ‘kernel_sendpage’:
> ./include/asm-generic/bug.h:97:3: error: too few arguments to function ‘__warn_printk’
>    97 |   __warn_printk(arg);     \
>       |   ^~~~~~~~~~~~~
> 
> Was this even build tested?
> 

Hi David,

Obviously my fault and no excuse for leaking this uncompleted version to
you. I just re-post a v10 version which I make sure all patches are the
latest version.

Sorry for the inconvenience and thank you in advance for taking this set.

Coly Li

David Miller Oct. 2, 2020, 10:29 p.m. UTC | #4

From: Coly Li <[e-mail]>
Date: Fri, 2 Oct 2020 16:30:12 +0800

> Obviously my fault and no excuse for leaking this uncompleted version to
> you. I just re-post a v10 version which I make sure all patches are the
> latest version.
> 
> Sorry for the inconvenience and thank you in advance for taking this set.

How did this happen?

How did you functionally test the patch set if it didn't even compile?

I want you to explain why you sent a completely untested patch set.