There is a negative offset of an on-stack array that causes an out of bounds issue when someone called with a zero 'count' argument to syswrite(). buf[count - 1] We should add an extra check in rproc_coredump_write() to prevent the access. Signed-off-by: Xiaobing shi <xiaobing.shi@xxxxxxxxxxxx> --- drivers/remoteproc/remoteproc_debugfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c index b5a1e3b697d9..581930483ef8 100644 --- a/drivers/remoteproc/remoteproc_debugfs.c +++ b/drivers/remoteproc/remoteproc_debugfs.c @@ -76,7 +76,7 @@ static ssize_t rproc_coredump_write(struct file *filp, int ret, err = 0; char buf[20]; - if (count > sizeof(buf)) + if (count < 1 || count > sizeof(buf)) return -EINVAL; ret = copy_from_user(buf, user_buf, count); -- 2.18.0