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Date: Fri, 16 Dec 2005 01:55:05 +0100
From: Adrian Bunk <bunk@stusta.de>
To: Kyungmin Park <kyungmin.park@samsung.com>
Message-ID: <20051216005505.GW23349@stusta.de>
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Cc: Andrew Morton <akpm@osdl.org>, linux-mtd@lists.infradead.org,
	Linus Torvalds <torvalds@osdl.org>, dwmw2@infradead.org,
	linux-kernel@vger.kernel.org
Subject: drivers/mtd/onenand/: unacceptable stack usage
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In 2.6.15-rc, the following driver was added:


include/linux/mtd/onenand.h:
#define MAX_ONENAND_PAGESIZE        (2048 + 64)


drivers/mtd/onenand/onenand_base.c:
static int onenand_writev_ecc(struct mtd_info *mtd, const struct kvec *vecs,
        unsigned long count, loff_t to, size_t *retlen,
        u_char *eccbuf, struct nand_oobinfo *oobsel)
{
        struct onenand_chip *this = mtd->priv;
        unsigned char buffer[MAX_ONENAND_PAGESIZE], *pbuf;


drivers/mtd/onenand/onenand_bbt.c:
static inline int onenand_memory_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd)
{
        unsigned char data_buf[MAX_ONENAND_PAGESIZE];


These are variables on the stack that are > 2kB which is not acceptable 
since the complete stack might be only 4kB.


Please either fix this before 2.6.15 or mark the MTD_ONENAND driver as 
BROKEN until it's fixed.


TIA
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed