5.4-stable review patch. If anyone has any objections, please let me know.
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From: Zhen Ni zhen.ni@easystack.cn
commit d3366a04770eea807f2826cbdb96934dd8c9bf79 upstream.
Struct ff_effect_compat is embedded twice inside uinput_ff_upload_compat, contains internal padding. In particular, there is a hole after struct ff_replay to satisfy alignment requirements for the following union member. Without clearing the structure, copy_to_user() may leak stack data to userspace.
Initialize ff_up_compat to zero before filling valid fields.
Fixes: 2d56f3a32c0e ("Input: refactor evdev 32bit compat to be shareable with uinput") Cc: stable@vger.kernel.org Signed-off-by: Zhen Ni zhen.ni@easystack.cn Link: https://lore.kernel.org/r/20250928063737.74590-1-zhen.ni@easystack.cn Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/input/misc/uinput.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/input/misc/uinput.c +++ b/drivers/input/misc/uinput.c @@ -740,6 +740,7 @@ static int uinput_ff_upload_to_user(char if (in_compat_syscall()) { struct uinput_ff_upload_compat ff_up_compat;
+ memset(&ff_up_compat, 0, sizeof(ff_up_compat)); ff_up_compat.request_id = ff_up->request_id; ff_up_compat.retval = ff_up->retval; /*