path: root/sys/sys
diff options
authorRoy Marples <roy@marples.name>2021-07-28 15:46:59 +0000
committerKevin Bowling <kbowling@FreeBSD.org>2021-07-28 16:35:09 +0000
commit7045b1603bdf054145dd958a4acc17b410fb62a0 (patch)
tree9802ca364b6612648e33425e92b0f53f40799308 /sys/sys
parent33ff39796ffe469a764e485ac49c31700a51fd6f (diff)
socket: Implement SO_RERROR
SO_RERROR indicates that receive buffer overflows should be handled as errors. Historically receive buffer overflows have been ignored and programs could not tell if they missed messages or messages had been truncated because of overflows. Since programs historically do not expect to get receive overflow errors, this behavior is not the default. This is really really important for programs that use route(4) to keep in sync with the system. If we loose a message then we need to reload the full system state, otherwise the behaviour from that point is undefined and can lead to chasing bogus bug reports. Reviewed by: philip (network), kbowling (transport), gbe (manpages) MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D26652
Diffstat (limited to 'sys/sys')
2 files changed, 6 insertions, 1 deletions
diff --git a/sys/sys/socket.h b/sys/sys/socket.h
index d9256fd7544a..2cb76f9c6d63 100644
--- a/sys/sys/socket.h
+++ b/sys/sys/socket.h
@@ -147,6 +147,7 @@ typedef __uintptr_t uintptr_t;
#define SO_NO_OFFLOAD 0x00004000 /* socket cannot be offloaded */
#define SO_NO_DDP 0x00008000 /* disable direct data placement */
#define SO_REUSEPORT_LB 0x00010000 /* reuse with load balancing */
+#define SO_RERROR 0x00020000 /* keep track of receive errors */
* Additional options, not kept in so_options.
diff --git a/sys/sys/socketvar.h b/sys/sys/socketvar.h
index dbd9804a980d..47033fdabbfa 100644
--- a/sys/sys/socketvar.h
+++ b/sys/sys/socketvar.h
@@ -100,6 +100,7 @@ struct socket {
struct protosw *so_proto; /* (a) protocol handle */
short so_timeo; /* (g) connection timeout */
u_short so_error; /* (f) error affecting connection */
+ u_short so_rerror; /* (f) error affecting connection */
struct sigio *so_sigio; /* [sg] information for async I/O or
out of band data (SIGURG) */
struct ucred *so_cred; /* (a) user credentials */
@@ -266,7 +267,8 @@ struct socket {
/* can we read something from so? */
#define soreadabledata(so) \
- (sbavail(&(so)->so_rcv) >= (so)->so_rcv.sb_lowat || (so)->so_error)
+ (sbavail(&(so)->so_rcv) >= (so)->so_rcv.sb_lowat || \
+ (so)->so_error || (so)->so_rerror)
#define soreadable(so) \
(soreadabledata(so) || ((so)->so_rcv.sb_state & SBS_CANTRCVMORE))
@@ -480,6 +482,8 @@ void socantrcvmore(struct socket *so);
void socantrcvmore_locked(struct socket *so);
void socantsendmore(struct socket *so);
void socantsendmore_locked(struct socket *so);
+void soroverflow(struct socket *so);
+void soroverflow_locked(struct socket *so);
* Accept filter functions (duh).