linux-kernel - Hopefully, kmalloc() will always succeed, but if it doesn't then....

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Message-ID: <20061022195809.30126.qmail@web55607.mail.re4.yahoo.com>
Date:	Sun, 22 Oct 2006 12:58:08 -0700 (PDT)
From:	Amit Choudhary <amit2030@...oo.com>
To:	linux-kernel@...r.kernel.org
Subject: Hopefully, kmalloc() will always succeed, but if it doesn't then....

Hi All,

Hopefully, kmalloc() should always succeed. But if it doesn't then the kernel is going to crash
left and right. But I guess that there's no point in running if there is no memory. Anyways, here
is what I found at many places:

func()
{
   char *a; 
   char *b;

   a = kmalloc(10, GFP_KERNEL);
   if (!a)
       goto error;

   b = kmalloc(10, GFP_KERNEL);
   if (!b)
       goto error;

 error:
  kfree(a);
  kfree(b);

}

So, if memory allocation to 'a' fails, it is going to kfree 'b'. But since 'b' is not initialized,
 kfree may crash (unless DEBUG is defined).

I have seen the same case at many places when allocating in a loop.

Regards,
Amit 

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