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Date: Mon, 10 Oct 2011 12:28:57 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Artem Bityutskiy <dedekind1@gmail.com>
Subject: [smatch stuff] mtd/ubi/gluebi: signedness warnings
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Smatch complains about some to the checks in gluebi.c

drivers/mtd/ubi/gluebi.c +177 gluebi_read(6) warn: unsigned 'len' is never less than zero.
drivers/mtd/ubi/gluebi.c +221 gluebi_write(6) warn: unsigned 'len' is never less than zero.
drivers/mtd/ubi/gluebi.c +270 gluebi_erase(7) warn: unsigned 'instr->len' is never less than zero.

I think probably these checks can just be removed?  Can these things
wrap if we passed a huge value for instr->len?

   270          if (instr->len < 0 || instr->addr + instr->len > mtd->size)
   271                  return -EINVAL;

I don't know enough about how these are called to say.

regards,
dan carpenter