From: Dingchen Zhang <dingchen.zhang@xxxxxxx> [ Upstream commit 72a848f5c46bab4c921edc9cbffd1ab273b2be17 ] userspace may transfer a newline, and this terminating newline is replaced by a '\0' to avoid followup issues. 'len-1' is the index to replace the newline of CRC source name. v3: typo fix (Sam) v2: update patch subject, body and format. (Sam) Cc: Leo Li <sunpeng.li@xxxxxxx> Cc: Harry Wentland <Harry.Wentland@xxxxxxx> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx> Signed-off-by: Dingchen Zhang <dingchen.zhang@xxxxxxx> Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20190610134751.14356-1-dingchen.zhang@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/drm_debugfs_crc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c index be1b7ba92ffe1..6a626c82e264b 100644 --- a/drivers/gpu/drm/drm_debugfs_crc.c +++ b/drivers/gpu/drm/drm_debugfs_crc.c @@ -140,8 +140,8 @@ static ssize_t crc_control_write(struct file *file, const char __user *ubuf, if (IS_ERR(source)) return PTR_ERR(source); - if (source[len] == '\n') - source[len] = '\0'; + if (source[len - 1] == '\n') + source[len - 1] = '\0'; ret = crtc->funcs->verify_crc_source(crtc, source, &values_cnt); if (ret) -- 2.20.1