From c804c00d38f6a848f0d7e57a05ea5468fc5762b2 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 26 Mar 2017 17:35:35 -0400 Subject: [PATCH] Fix unportable disregard of alignment requirements in RADIUS code. The compiler is entitled to store a char[] local variable with no particular alignment requirement. Our RADIUS code cavalierly took such a local variable and cast its address to a struct type that does have alignment requirements. On an alignment-picky machine this would lead to bus errors. To fix, declare the local variable honestly, and then cast its address to char * for use in the I/O calls. Given the lack of field complaints, there must be very few if any people affected; but nonetheless this is a clear portability issue, so back-patch to all supported branches. Noted while looking at a Coverity complaint in the same code. --- src/backend/libpq/auth.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c index 127c6cf45e9f7..f585ae0aed991 100644 --- a/src/backend/libpq/auth.c +++ b/src/backend/libpq/auth.c @@ -2355,14 +2355,16 @@ CheckCertAuth(Port *port) */ /* - * RADIUS authentication is described in RFC2865 (and several - * others). + * RADIUS authentication is described in RFC2865 (and several others). */ #define RADIUS_VECTOR_LENGTH 16 #define RADIUS_HEADER_LENGTH 20 #define RADIUS_MAX_PASSWORD_LENGTH 128 +/* Maximum size of a RADIUS packet we will create or accept */ +#define RADIUS_BUFFER_SIZE 1024 + typedef struct { uint8 attribute; @@ -2376,6 +2378,8 @@ typedef struct uint8 id; uint16 length; uint8 vector[RADIUS_VECTOR_LENGTH]; + /* this is a bit longer than strictly necessary: */ + char pad[RADIUS_BUFFER_SIZE - RADIUS_VECTOR_LENGTH]; } radius_packet; /* RADIUS packet types */ @@ -2392,9 +2396,6 @@ typedef struct /* RADIUS service types */ #define RADIUS_AUTHENTICATE_ONLY 8 -/* Maximum size of a RADIUS packet we will create or accept */ -#define RADIUS_BUFFER_SIZE 1024 - /* Seconds to wait - XXX: should be in a config variable! */ #define RADIUS_TIMEOUT 3 @@ -2429,10 +2430,12 @@ CheckRADIUSAuth(Port *port) { char *passwd; char *identifier = "postgresql"; - char radius_buffer[RADIUS_BUFFER_SIZE]; - char receive_buffer[RADIUS_BUFFER_SIZE]; - radius_packet *packet = (radius_packet *) radius_buffer; - radius_packet *receivepacket = (radius_packet *) receive_buffer; + radius_packet radius_send_pack; + radius_packet radius_recv_pack; + radius_packet *packet = &radius_send_pack; + radius_packet *receivepacket = &radius_recv_pack; + char *radius_buffer = (char *) &radius_send_pack; + char *receive_buffer = (char *) &radius_recv_pack; int32 service = htonl(RADIUS_AUTHENTICATE_ONLY); uint8 *cryptvector; int encryptedpasswordlen;