RE: [PATCH] USB: gadget: f_mass_storage: fix in fsg_common_init()error recovery

From: Viral Mehta
Date: Wed May 12 2010 - 06:06:32 EST


>> Apart from that, IMHO,
>> 2894 kfree(common->luns);
>> should crash in case if your error path is followed.
>>
>> common->luns is allocd
>> 2712 /* Create the LUNs, open their backing files, and register the
>> 2713 * LUN devices in sysfs. */
>> 2714 curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
>> 2715 if (!curlun) {
>> 2716 kfree(common);
>> 2717 return ERR_PTR(-ENOMEM);
>> 2718 }

>Yes, that's why the submitted patch changes that to "rc = -ENOMEM;
>goto errer_release;".

I think you misread.
In fsg_common_release(), we are freeing common->luns.
2894 kfree(common->luns);

However, these gets allocd in fsg_common_init()
2712 /* Create the LUNs, open their backing files, and register the
2713 * LUN devices in sysfs. */
2714 curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
2715 if (!curlun) {
2716 kfree(common);
2717 return ERR_PTR(-ENOMEM);
2718 }


Now, if this kzalloc at line 2714 failed
And if your patch is applied, you will follow error_release path which in turn will call kfree on a pointer whose allocation is failed.

And this is true for the HUNK#1 as well.

Getting ? So, i still think the patch I sent looks simple and correct.




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