From: Anjaneyulu <pagadala.yesu.anjaneyulu@xxxxxxxxx> The driver copies the userspace buffer into an internal NUL byte terminated buffer. While doing so, it was reading beyond the end of the userspace buffer, overwriting its own NUL termination in the process. Fix this by only copying the correct number of bytes. Fixes: 3f244876ef73 ("wifi: iwlwifi: make debugfs entries link specific") Signed-off-by: Anjaneyulu <pagadala.yesu.anjaneyulu@xxxxxxxxx> Reviewed-by: Gregory Greenman <gregory.greenman@xxxxxxxxx> Reviewed-by: Benjamin Berg <benjamin.berg@xxxxxxxxx> Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@xxxxxxxxx> --- drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c index e016fce7ab24..16a104de8371 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c @@ -1829,7 +1829,7 @@ static ssize_t _iwl_dbgfs_link_sta_##name##_write(struct file *file, \ char buf[buflen] = {}; \ size_t buf_size = min(count, sizeof(buf) - 1); \ \ - if (copy_from_user(buf, user_buf, sizeof(buf))) \ + if (copy_from_user(buf, user_buf, buf_size)) \ return -EFAULT; \ \ return _iwl_dbgfs_link_sta_wrap_write(iwl_dbgfs_##name##_write, \ -- 2.34.1