mtd: onenand: Fix uninitialized retlen in do_otp_read()

commit 70a71f8151b9879b0950668ce3ad76263261fee0 upstream.

The function do_otp_read() does not set the output parameter *retlen,
which is expected to contain the number of bytes actually read.
As a result, in onenand_otp_walk(), the tmp_retlen variable remains
uninitialized after calling do_otp_walk() and used to change
the values of the buf, len and retlen variables.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 49dc08eeda70 ("[MTD] [OneNAND] fix numerous races")
Cc: stable@vger.kernel.org
Signed-off-by: Ivan Stepchenko <sid@itb.spb.ru>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/mtd/nand/onenand/onenand_base.c b/drivers/mtd/nand/onenand/onenand_base.c
index 188b8061e1f793ede6f86db8b4b2a63e2fec7849..7ac3f498709d7b3661a8b2447c03d67cf3415f3c 100644 (file)
--- a/drivers/mtd/nand/onenand/onenand_base.c
+++ b/drivers/mtd/nand/onenand/onenand_base.c
@@ -2916,6 +2916,7 @@ static int do_otp_read(struct mtd_info *mtd, loff_t from, size_t len,
        ret = ONENAND_IS_4KB_PAGE(this) ?
                onenand_mlc_read_ops_nolock(mtd, from, &ops) :
                onenand_read_ops_nolock(mtd, from, &ops);
+       *retlen = ops.retlen;
 
        /* Exit OTP access mode */
        this->command(mtd, ONENAND_CMD_RESET, 0, 0);