| Message ID | 20190930140207.28638-1-efremov@linux.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | ar5523: check NULL before memcpy() in ar5523_cmd() | expand |
From: Denis Efremov > Sent: 30 September 2019 15:02 > > 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. > ... > 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); That would be better as if (ilen) ... David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
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;
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(-)