From 3557094f407c744e12b38fc4ddd5ee28b3ba1cbb Mon Sep 17 00:00:00 2001 From: Denis Efremov Date: Mon, 30 Sep 2019 23:31:47 +0300 Subject: ar5523: check NULL before memcpy() in ar5523_cmd() commit 315cee426f87658a6799815845788fde965ddaad upstream. memcpy() call with "idata == NULL && ilen == 0" results in undefined behavior in ar5523_cmd(). For example, NULL is passed in callchain "ar5523_stat_work() -> ar5523_cmd_write() -> ar5523_cmd()". This patch adds ilen check before memcpy() call in ar5523_cmd() to prevent an undefined behavior. Cc: Pontus Fuchs Cc: Kalle Valo Cc: "David S. Miller" Cc: David Laight Cc: stable@vger.kernel.org Signed-off-by: Denis Efremov Signed-off-by: Kalle Valo Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/ath/ar5523/ar5523.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/net/wireless/ath/ar5523/ar5523.c b/drivers/net/wireless/ath/ar5523/ar5523.c index 68f0463ed8df..ad4a1efc57c9 100644 --- a/drivers/net/wireless/ath/ar5523/ar5523.c +++ b/drivers/net/wireless/ath/ar5523/ar5523.c @@ -255,7 +255,8 @@ static int ar5523_cmd(struct ar5523 *ar, u32 code, const void *idata, if (flags & AR5523_CMD_FLAG_MAGIC) hdr->magic = cpu_to_be32(1 << 24); - memcpy(hdr + 1, idata, ilen); + if (ilen) + memcpy(hdr + 1, idata, ilen); cmd->odata = odata; cmd->olen = olen; -- cgit v1.2.3