commit: 7a84477c4acebf6299b6a8bd6a1d5894eb838ffa From: Will Newton <[email protected]> Date: Fri, 30 Mar 2012 11:51:02 +0100 Subject: mtd: fix oops in dataflash driver
I'm seeing an oops in mtd_dataflash.c with Linux 3.3. What appears to be happening is that otp_select_filemode calls mtd_read_fact_prot_reg with -1 for offset and length and a NULL buffer to test if OTP operations are supported. This finds its way down to otp_read in mtd_dataflash.c and causes an oops when memcpying the returned data into the NULL buf. None of the checks in otp_read catches the negative length and offset. Changing the length of the dummy read to 0 prevents the oops. Cc: [email protected] [3.3+] Signed-off-by: Artem Bityutskiy <[email protected]> Signed-off-by: David Woodhouse <[email protected]> --- drivers/mtd/mtdchar.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c index 58fc65f..f2f482b 100644 --- a/drivers/mtd/mtdchar.c +++ b/drivers/mtd/mtdchar.c @@ -376,7 +376,7 @@ static int otp_select_filemode(struct mtd_file_info *mfi, int mode) * Make a fake call to mtd_read_fact_prot_reg() to check if OTP * operations are supported. */ - if (mtd_read_fact_prot_reg(mtd, -1, -1, &retlen, NULL) == -EOPNOTSUPP) + if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) == -EOPNOTSUPP) return -EOPNOTSUPP; switch (mode) { -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
