| Message ID | 20170613164428.3643-1-mjurczyk@google.com |
|---|---|
| State | Awaiting Upstream, archived |
| Delegated to: | David Miller |
| Headers | show |
On Tue, Jun 13, 2017 at 06:44:28PM +0200, Mateusz Jurczyk wrote: > Verify that the caller-provided sockaddr structure is large enough to > contain the sa_family field, before accessing it in bind() handlers of the > AF_NFC socket. Since the syscall doesn't enforce a minimum size of the > corresponding memory region, very short sockaddrs (zero or one byte long) > result in operating on uninitialized memory while referencing .sa_family. > > Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com> > --- > net/nfc/llcp_sock.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) Applied to nfc-next, thanks. Cheers, Samuel.
diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c index 2ffb18e73df6..80cf35ed320a 100644 --- a/net/nfc/llcp_sock.c +++ b/net/nfc/llcp_sock.c @@ -77,7 +77,8 @@ static int llcp_sock_bind(struct socket *sock, struct sockaddr *addr, int alen) struct sockaddr_nfc_llcp llcp_addr; int len, ret = 0; - if (!addr || addr->sa_family != AF_NFC) + if (!addr || alen < offsetofend(struct sockaddr, sa_family) || + addr->sa_family != AF_NFC) return -EINVAL; pr_debug("sk %p addr %p family %d\n", sk, addr, addr->sa_family); @@ -151,7 +152,8 @@ static int llcp_raw_sock_bind(struct socket *sock, struct sockaddr *addr, struct sockaddr_nfc_llcp llcp_addr; int len, ret = 0; - if (!addr || addr->sa_family != AF_NFC) + if (!addr || alen < offsetofend(struct sockaddr, sa_family) || + addr->sa_family != AF_NFC) return -EINVAL; pr_debug("sk %p addr %p family %d\n", sk, addr, addr->sa_family);
Verify that the caller-provided sockaddr structure is large enough to contain the sa_family field, before accessing it in bind() handlers of the AF_NFC socket. Since the syscall doesn't enforce a minimum size of the corresponding memory region, very short sockaddrs (zero or one byte long) result in operating on uninitialized memory while referencing .sa_family. Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com> --- net/nfc/llcp_sock.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)