From ab92ed206d41fd171ebd37bc46360d9f2140d043 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 25 May 2026 10:16:27 +0300 Subject: [PATCH] iio: core: fix uninitialized data in debugfs If *ppos is non-zero then simple_write_to_buffer() will not initialize the start of buf[]. Non zero values for *ppos aren't going to work anyway. Test for them at the start of the function and return -EINVAL. Fixes: 6d5dd486c715 ("iio: core: make use of simple_write_to_buffer()") Signed-off-by: Dan Carpenter Reviewed-by: Maxwell Doose Cc: Signed-off-by: Jonathan Cameron --- drivers/iio/industrialio-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 22eefd048ba92..15b56f8972fc9 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -418,7 +418,7 @@ static ssize_t iio_debugfs_write_reg(struct file *file, char buf[80]; int ret; - if (count >= sizeof(buf)) + if (*ppos != 0 || count >= sizeof(buf)) return -EINVAL; ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, userbuf, -- 2.47.3