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Message-ID: <b2762a93-c8e3-f467-aed6-37c7e124f7c8@huawei.com>
Date: Mon, 11 Mar 2024 15:35:29 +0800
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Subject: Re: [PATCH v3 1/3] scsi: libsas: Allow smp_execute_task() arguments
 to be on the stack
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To: Dan Carpenter <dan.carpenter@linaro.org>, <oe-kbuild@lists.linux.dev>,
	<john.g.garry@oracle.com>, <yanaijie@huawei.com>, <jejb@linux.ibm.com>,
	<martin.petersen@oracle.com>, <damien.lemoal@opensource.wdc.com>
CC: <lkp@intel.com>, <oe-kbuild-all@lists.linux.dev>,
	<linux-scsi@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linuxarm@huawei.com>, <prime.zeng@hisilicon.com>,
	<chenxiang66@hisilicon.com>, <kangfenglong@huawei.com>
References: <0cf17536-beba-4a8f-836b-553a9e0d1046@moroto.mountain>
From: yangxingui <yangxingui@huawei.com>
In-Reply-To: <0cf17536-beba-4a8f-836b-553a9e0d1046@moroto.mountain>
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On 2024/3/11 13:42, Dan Carpenter wrote:
> Hi Xingui,
> 
> kernel test robot noticed the following build warnings:
> 
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Xingui-Yang/scsi-libsas-Allow-smp_execute_task-arguments-to-be-on-the-stack/20240307-174215
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/mkp/scsi.git for-next
> patch link:    https://lore.kernel.org/r/20240307093733.41222-2-yangxingui%40huawei.com
> patch subject: [PATCH v3 1/3] scsi: libsas: Allow smp_execute_task() arguments to be on the stack
> config: i386-randconfig-141-20240308 (https://download.01.org/0day-ci/archive/20240310/202403102353.jUPi6fOP-lkp@intel.com/config)
> compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> | Closes: https://lore.kernel.org/r/202403102353.jUPi6fOP-lkp@intel.com/
> 
> New smatch warnings:
> drivers/scsi/libsas/sas_expander.c:148 smp_execute_task() warn: possible memory leak of '_req'
> 
> vim +/_req +148 drivers/scsi/libsas/sas_expander.c
> 
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  138  static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  139  			    void *resp, int resp_size)
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  140  {
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  141  	struct scatterlist req_sg;
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  142  	struct scatterlist resp_sg;
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  143  	void *_req = kmemdup(req, req_size, GFP_KERNEL);
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  144  	void *_resp = alloc_smp_resp(resp_size);
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  145  	int ret;
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  146
> adfd2325dfc5cf6 Xingui Yang     2024-03-07  147  	if (!_req || !resp)
> adfd2325dfc5cf6 Xingui Yang     2024-03-07 @148  		return -ENOMEM;
> 
> I haven't looked at the callers so I don't know how likely it is for one
> of the allocations to fail and the other succeed...  But it seems
> possible.

Yes, it's possible. This patch has been canceled in v4. Based on John's 
suggestion, if there are plans to resubmit modifications , we will pay 
attention to this, thank you.

Thanks,
Xingui