Messages in this thread | | | Date | Mon, 12 Aug 2013 14:26:50 -0300 | From | Ezequiel Garcia <> | Subject | Re: [PATCH 1/1] mtd: mtdoops: fix for a potential memory leak in mtdoops_notify_remove |
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On Sun, Aug 11, 2013 at 01:11:48PM -0700, Nilanjan Roychowdhury wrote: > we are allocating cxt->oops_page_used using vmalloc in mtdoops_notify_add for > every mtd_info addition but not freeing it in mtdoops_notify_remove > > Signed-off-by: Nilanjan Roychowdhury <nilanjan.roychowdhury@gmail.com> > --- > drivers/mtd/mtdoops.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c > index 97bb8f6..02f49aa 100644 > --- a/drivers/mtd/mtdoops.c > +++ b/drivers/mtd/mtdoops.c > @@ -386,6 +386,7 @@ static void mtdoops_notify_remove(struct mtd_info *mtd) > cxt->mtd = NULL; > flush_work(&cxt->work_erase); > flush_work(&cxt->work_write); > + vfree(cxt->oops_page_used); > } > > -- > 1.7.9.5 >
Have you tested this patch doing an unregister/module remove cycle?
I'm not entirely sure, but I *think* you must also remove the vfree(cxt->oops_page_used); at mtdoops_exit(). Otherwise, you might call vfree() twice, the second time on a garbage pointer.
The reason for this is that the unregister_mtd_user(&mtdoops_notifier); call in mtdoops_exit() will call the .remove callback (causing the first vfree() with this patch) and then call vfree() for the second time, explicitly. -- Ezequiel García, Free Electrons Embedded Linux, Kernel and Android Engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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