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 idata check before memcpy() call in ar5523_cmd() to prevent an undefined behavior.
Cc: Pontus Fuchs pontus.fuchs@gmail.com Cc: Kalle Valo kvalo@codeaurora.org Cc: "David S. Miller" davem@davemloft.net Cc: stable@vger.kernel.org Signed-off-by: Denis Efremov efremov@linux.com --- drivers/net/wireless/ath/ar5523/ar5523.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ar5523/ar5523.c b/drivers/net/wireless/ath/ar5523/ar5523.c index b94759daeacc..f25af5bc5282 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 (idata) + memcpy(hdr + 1, idata, ilen);
cmd->odata = odata; cmd->olen = olen;