[PATCH] mtd: onenand: Fix uninitialized retlen in do_otp_read()

[PATCH] mtd: onenand: Fix uninitialized retlen in do_otp_read()

[Ivan Stepchenko]

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>
---
 drivers/mtd/nand/onenand/onenand_base.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/mtd/nand/onenand/onenand_base.c b/drivers/mtd/nand/onenand/onenand_base.c
index f66385faf631..0dc2ea4fc857 100644
--- a/drivers/mtd/nand/onenand/onenand_base.c
+++ b/drivers/mtd/nand/onenand/onenand_base.c
@@ -2923,6 +2923,7 @@ 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);
-- 
2.34.1

Re: [PATCH] mtd: onenand: Fix uninitialized retlen in do_otp_read()

[Miquel Raynal]

On Thu, 14 Nov 2024 16:29:51 +0300, Ivan Stepchenko wrote:
> 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.
> 
> [...]

Applied to nand/next, thanks!

[1/1] mtd: onenand: Fix uninitialized retlen in do_otp_read()

Patche(s) will be available within hours on:
mtd/linux.git

Kind regards,
Miquèl