Re: Possible memory leak in request_firmware()

From: David Woodhouse
Date: Wed Jul 08 2009 - 02:29:02 EST


On Wed, 2009-07-08 at 12:38 +0800, Ming Lei wrote:
> 2009/7/8 Catalin Marinas <catalin.marinas@xxxxxxx>:
> > On Tue, 2009-07-07 at 19:01 +0200, Cornelia Huck wrote:
> >
> > There is one more leak in this area which I couldn't figure out where it
> > should be freed:
> >
> > unreferenced object 0xc353e530 (size 512):
> > comm "cat", pid 3130, jiffies 4294903232
> > backtrace:
> > [<c01e6f6a>] create_object+0xfa/0x250
> > [<c01e753d>] kmemleak_alloc+0x5d/0x70
> > [<c01e223d>] __kmalloc+0x10d/0x210
> > [<c03b2d2f>] firmware_data_write+0x1df/0x270
> > [<c024163a>] write+0x13a/0x1b0
> > [<c01eae1c>] vfs_write+0x9c/0x190
> > [<c01eafcd>] sys_write+0x3d/0x70
> > [<c010319c>] sysenter_do_call+0x12/0x38
> > [<ffffffff>] 0xffffffff
> >
> > Any idea? It looks like this is the kmalloc() in fw_realloc_buffer()
> > (inlined in firmware_data_write).
>
> I guess the leak is introduced in commit :
> commit 6e03a201bbe8137487f340d26aa662110e324b20
> firmware: speed up request_firmware(), v3
>
> The attachment patch may fix the leak, please test and verify it.
> Thanks.

I think you need to stop it from clearing fw_priv->nr_pages too.
With that change, it looks correct. Thanks.

Acked-by: David Woodhouse <David.Woodhouse@xxxxxxxxx>

--
David Woodhouse Open Source Technology Centre
David.Woodhouse@xxxxxxxxx Intel Corporation

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/