From: Larry Finger <Larry.Finger@xxxxxxxxxxxx> commit 499c405b2b80bb3a04425ba3541d20305e014d3e upstream. In routine rtw_hostapd_ioctl(), the user-controlled p->length is assumed to be at least the size of struct ieee_param size, but this assumption is never checked. This could result in out-of-bounds read/write on kernel heap in case a p->length less than the size of struct ieee_param is specified by the user. If p->length is allowed to be greater than the size of the struct, then a malicious user could be wasting kernel memory. Fixes commit a2c60d42d97c ("Add files for new driver - part 16"). Reported by: Pietro Oliva <pietroliva@xxxxxxxxx> Cc: Pietro Oliva <pietroliva@xxxxxxxxx> Cc: Stable <stable@xxxxxxxxxxxxxxx> Fixes: a2c60d42d97c ("staging: r8188eu: Add files for new driver - part 16") Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200210180235.21691-2-Larry.Finger@xxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/rtl8188eu/os_dep/ioctl_linux.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c +++ b/drivers/staging/rtl8188eu/os_dep/ioctl_linux.c @@ -2812,7 +2812,7 @@ static int rtw_hostapd_ioctl(struct net_ goto out; } - if (!p->pointer) { + if (!p->pointer || p->length != sizeof(struct ieee_param)) { ret = -EINVAL; goto out; }