[lvc-project] [PATCH v2 5.10/5.15] RDMA/rxe: Fix the error "trying to register non-static key in rxe_cleanup_task"

[Fedor Pchelkin]

On Wed, 03. Jun 15:18, Vladislav Nikolaev wrote:
> From: Zhu Yanjun <yanjun.zhu at linux.dev>
> 
> commit b2b1ddc457458fecd1c6f385baa9fbda5f0c63ad upstream.
> 
> In the function rxe_create_qp(), rxe_qp_from_init() is called to
> initialize qp, internally things like rxe_init_task are not setup until
> rxe_qp_init_req().
> 
> If an error occurred before this point then the unwind will call
> rxe_cleanup() and eventually to rxe_qp_do_cleanup()/rxe_cleanup_task()
> which will oops when trying to access the uninitialized spinlock.
> 
> If rxe_init_task is not executed, rxe_cleanup_task will not be called.
> 
> Reported-by: syzbot+cfcc1a3c85be15a40cba at syzkaller.appspotmail.com
> Link: https://syzkaller.appspot.com/bug?id=fd85757b74b3eb59f904138486f755f71e090df8
> Fixes: 8700e3e7c485 ("Soft RoCE driver")
> Fixes: 2d4b21e0a291 ("IB/rxe: Prevent from completer to operate on non valid QP")
> Signed-off-by: Zhu Yanjun <yanjun.zhu at linux.dev>
> Link: https://lore.kernel.org/r/20230413101115.1366068-1-yanjun.zhu@intel.com
> Signed-off-by: Leon Romanovsky <leon at kernel.org>
> [ Vladislav: match upstream cleanup order and add the missing
> resp.task.func check. ]
> Signed-off-by: Vladislav Nikolaev <vlad102nikolaev at gmail.com>
> ---

Thanks for the update.

> v2: Move rxe_cleanup_task(&qp->resp.task) after RC timer cleanup.
> Add missing qp->resp.task.func check before cleaning up the responder task.

I did actually suggest only adding a corresponding check for the
rxe_cleanup_task(&qp->resp.task) call which the upstream commit performs.
Moving it a couple of lines around requires some explanation why it's
okay in 5.10/5.15 kernels.  Note that in upstream it was done by another
commit 960ebe97e523 ("RDMA/rxe: Remove __rxe_do_task()").

[ yeah, it should be safe to move the call but it'd better be stated
  explicitly in the backporter's comment ]

Worth saying that checkpatch.pl for the current patch gives:

ERROR: trailing whitespace
#52: FILE: drivers/infiniband/sw/rxe/rxe_qp.c:771:
+^I$

You might also want to consider porting 1c7eec4d5f3b ("RDMA/rxe: Fix
"trying to register non-static key in rxe_qp_do_cleanup" bug") which fixes
the similar problem for del_timer_sync / timer_delete_sync calls in this
code.  This all could go as a series now probably.