Re: [PATCH 1/1] RDMA/rxe: Fix slab-use-after-free Read in rxe_queue_cleanup bug

[Zhu Yanjun <yanjun.zhu@linux.dev>]

On 14.04.25 12:49, Daisuke Matsuda (Fujitsu) wrote:
> On Sat, April 12, 2025 4:57 PM Zhu Yanjun wrote:
>>
>> Call Trace:
>>   <TASK>
>>   __dump_stack lib/dump_stack.c:94 [inline]
>>   dump_stack_lvl+0x7d/0xa0 lib/dump_stack.c:120
>>   print_address_description mm/kasan/report.c:378 [inline]
>>   print_report+0xcf/0x610 mm/kasan/report.c:489
>>   kasan_report+0xb5/0xe0 mm/kasan/report.c:602
>>   rxe_queue_cleanup+0xd0/0xe0 drivers/infiniband/sw/rxe/rxe_queue.c:195
>>   rxe_cq_cleanup+0x3f/0x50 drivers/infiniband/sw/rxe/rxe_cq.c:132
>>   __rxe_cleanup+0x168/0x300 drivers/infiniband/sw/rxe/rxe_pool.c:232
>>   rxe_create_cq+0x22e/0x3a0 drivers/infiniband/sw/rxe/rxe_verbs.c:1109
>>   create_cq+0x658/0xb90 drivers/infiniband/core/uverbs_cmd.c:1052
>>   ib_uverbs_create_cq+0xc7/0x120 drivers/infiniband/core/uverbs_cmd.c:1095
>>   ib_uverbs_write+0x969/0xc90 drivers/infiniband/core/uverbs_main.c:679
>>   vfs_write fs/read_write.c:677 [inline]
>>   vfs_write+0x26a/0xcc0 fs/read_write.c:659
>>   ksys_write+0x1b8/0x200 fs/read_write.c:731
>>   do_syscall_x64 arch/x86/entry/common.c:52 [inline]
>>   do_syscall_64+0xaa/0x1b0 arch/x86/entry/common.c:83
>>   entry_SYSCALL_64_after_hwframe+0x77/0x7f
>>
>> In the function rxe_create_cq, when rxe_cq_from_init fails, the function
>> rxe_cleanup will be called to handle the allocated resources. In fact,
>> some memory resources have already been freed in the function
>> rxe_cq_from_init. Thus, this problem will occur.
>>
>> The solution is to let rxe_cleanup do all the work.
>>
>> Fixes: 8700e3e7c485 ("Soft RoCE driver")
>> Link: https://paste.ubuntu.com/p/tJgC42wDf6/
>> Tested-by: liuyi <liuy22@mails.tsinghua.edu.cn>
>> Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
> 
> Reviewed-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
> 
> The fix looks correct.

Thanks a lot.

Zhu Yanjun

> Thank you.
> 
>> ---
>>   drivers/infiniband/sw/rxe/rxe_cq.c | 5 +----
>>   1 file changed, 1 insertion(+), 4 deletions(-)
>>
>> diff --git a/drivers/infiniband/sw/rxe/rxe_cq.c b/drivers/infiniband/sw/rxe/rxe_cq.c
>> index fec87c9030ab..fffd144d509e 100644
>> --- a/drivers/infiniband/sw/rxe/rxe_cq.c
>> +++ b/drivers/infiniband/sw/rxe/rxe_cq.c
>> @@ -56,11 +56,8 @@ int rxe_cq_from_init(struct rxe_dev *rxe, struct rxe_cq *cq, int cqe,
>>
>>   	err = do_mmap_info(rxe, uresp ? &uresp->mi : NULL, udata,
>>   			   cq->queue->buf, cq->queue->buf_size, &cq->queue->ip);
>> -	if (err) {
>> -		vfree(cq->queue->buf);
>> -		kfree(cq->queue);
>> +	if (err)
>>   		return err;
>> -	}
>>
>>   	cq->is_user = uresp;
>>
>> --
>> 2.34.1
>>