bgp_rpki module crashes in rare instances.

[donaldsharp]

Code crash:

(gdb) 
#0  __pthread_kill_implementation (no_tid=0, signo=6, threadid=136763135739456) at ./nptl/pthread_kill.c:44
#1  __pthread_kill_internal (signo=6, threadid=136763135739456) at ./nptl/pthread_kill.c:78
#2  __GI___pthread_kill (threadid=136763135739456, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
#3  0x00007c62a7e42476 in __GI_raise (sig=6) at ../sysdeps/posix/raise.c:26
#4  0x00007c62a8b382b8 in core_handler (signo=6, siginfo=0x7c62a61f9f70, context=0x7c62a61f9e40) at lib/sigevent.c:248
#5  <signal handler called>
#6  __pthread_kill_implementation (no_tid=0, signo=6, threadid=136763135739456) at ./nptl/pthread_kill.c:44
#7  __pthread_kill_internal (signo=6, threadid=136763135739456) at ./nptl/pthread_kill.c:78
#8  __GI___pthread_kill (threadid=136763135739456, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
#9  0x00007c62a7e42476 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#10 0x00007c62a7e287f3 in __GI_abort () at ./stdlib/abort.c:79
#11 0x00007c62a8b7cf45 in _zlog_assert_failed (xref=0x7c62a8c214a0 <rcu_read_lock._xref>, extra=0x0) at lib/zlog.c:670
#12 0x00007c62a8ab80d6 in rcu_read_lock () at lib/frrcu.c:294
#13 0x00007c62a8b7c8ee in vzlog_notls (xref=0x0, prio=2, fmt=0x7c62a8bc4fbb "%s:%d: %s(): assertion (%s) failed", ap=0x7c62a61fb250) at lib/zlog.c:425
#14 0x00007c62a8b7c58c in vzlogx (xref=0x0, prio=2, fmt=0x7c62a8bc4fbb "%s:%d: %s(): assertion (%s) failed", ap=0x7c62a61fb250) at lib/zlog.c:627
#15 0x00007c62a8b7d0a4 in zlog (prio=2, fmt=0x7c62a8bc4fbb "%s:%d: %s(): assertion (%s) failed") at ./lib/zlog.h:73
#16 0x00007c62a8b7d000 in _zlog_assert_failed (xref=0x7c62a8c214a0 <rcu_read_lock._xref>, extra=0x0) at lib/zlog.c:687
#17 0x00007c62a8ab80d6 in rcu_read_lock () at lib/frrcu.c:294
#18 0x00007c62a8b7c8ee in vzlog_notls (xref=0x7c62a8da42c0 <rpki_create_socket._xref>, prio=3, fmt=0x7c62a8d9ee95 "getaddrinfo: %s", ap=0x7c62a61fb890)
    at lib/zlog.c:425
#19 0x00007c62a8b7c58c in vzlogx (xref=0x7c62a8da42c0 <rpki_create_socket._xref>, prio=3, fmt=0x7c62a8d9ee95 "getaddrinfo: %s", ap=0x7c62a61fb890) at lib/zlog.c:627
#20 0x00007c62a8d952e5 in zlog_ref (xref=0x7c62a8da42c0 <rpki_create_socket._xref>, fmt=0x7c62a8d9ee95 "getaddrinfo: %s") at ./lib/zlog.h:84
#21 0x00007c62a8d98dba in rpki_create_socket (_cache=0x5dba80cf8570) at bgpd/bgp_rpki.c:1337
#22 0x00007c62a80ea643 in ?? () from /lib/x86_64-linux-gnu/librtr.so.0
#23 0x00007c62a80eaf69 in ?? () from /lib/x86_64-linux-gnu/librtr.so.0
#24 0x00007c62a7e94ac3 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#25 0x00007c62a7f26850 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81
(gdb) ```

Bisect of the code base leads us to:

commit b28fd4e (HEAD, refs/bisect/bad)
Author: Louis Scalbert [email protected]
Date: Tue Jan 23 11:52:59 2024 +0100

bgpd: fix res validity in rpki_create_socket

Fix coverity scanner issue 1575912 where res pointer is supposed to
valid in:

> socket = vrf_socket(res->ai_family, ...)

but is checked for validity a few lines later.

Note that vrf_getaddrinfo returns an error code if getaddrinfo() fails
to allocate res and in this case, rpki_create_socket() returns.

Fixes: a951752 ("bgpd: create cache server socket in vrf")
Signed-off-by: Louis Scalbert <[email protected]>```

[louis-6wind]

I get the bug everytime with this patch.

diff --git a/bgpd/bgp_rpki.c b/bgpd/bgp_rpki.c
index 94275762f6..8f66f99338 100644
--- a/bgpd/bgp_rpki.c
+++ b/bgpd/bgp_rpki.c
@@ -1333,11 +1333,10 @@ static int rpki_create_socket(void *_cache)
 	frr_with_privs (&bgpd_privs) {
 		ret = vrf_getaddrinfo(host, port, &hints, &res, vrf->vrf_id);
 	}
-	if (ret != 0) {
-		flog_err_sys(EC_LIB_SOCKET, "getaddrinfo: %s",
-			     gai_strerror(ret));
-		return -1;
-	}
+//	if (ret != 0) {
+		zlog_warn("getaddrinfo: debug");
+//		return -1;
+//	}
 
 	frr_with_privs (&bgpd_privs) {
 		socket = vrf_socket(res->ai_family, res->ai_socktype,

The issue is because rpki_create_socket() is a hook that is called from the rtrlib library. I need to find the root cause

[louis-6wind]

full backtrace

#0  raise (sig=<optimized out>) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007f6e21723798 in core_handler (signo=6, siginfo=0x7f6e1e502ef0, context=0x7f6e1e502dc0) at lib/sigevent.c:248
#2  <signal handler called>
#3  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#4  0x00007f6e2144e537 in __GI_abort () at abort.c:79
#5  0x00007f6e2176348e in _zlog_assert_failed (xref=0x7f6e2180c920 <_xref.16>, extra=0x0) at lib/zlog.c:670
#6  0x00007f6e216b1eda in rcu_read_lock () at lib/frrcu.c:294
#7  0x00007f6e21762da8 in vzlog_notls (xref=0x0, prio=2, fmt=0x7f6e217afe50 "%s:%d: %s(): assertion (%s) failed", ap=0x7f6e1e504248) at lib/zlog.c:425
#8  0x00007f6e217632fb in vzlogx (xref=0x0, prio=2, fmt=0x7f6e217afe50 "%s:%d: %s(): assertion (%s) failed", ap=0x7f6e1e504248) at lib/zlog.c:627
#9  0x00007f6e217621f5 in zlog (prio=2, fmt=0x7f6e217afe50 "%s:%d: %s(): assertion (%s) failed") at lib/zlog.h:73
#10 0x00007f6e21763596 in _zlog_assert_failed (xref=0x7f6e2180c920 <_xref.16>, extra=0x0) at lib/zlog.c:687
#11 0x00007f6e216b1eda in rcu_read_lock () at lib/frrcu.c:294
#12 0x00007f6e21762da8 in vzlog_notls (xref=0x7f6e21a50040 <_xref.68>, prio=4, fmt=0x7f6e21a4999f "getaddrinfo: debug", ap=0x7f6e1e504878) at lib/zlog.c:425
#13 0x00007f6e217632fb in vzlogx (xref=0x7f6e21a50040 <_xref.68>, prio=4, fmt=0x7f6e21a4999f "getaddrinfo: debug", ap=0x7f6e1e504878) at lib/zlog.c:627
#14 0x00007f6e21a3f774 in zlog_ref (xref=0x7f6e21a50040 <_xref.68>, fmt=0x7f6e21a4999f "getaddrinfo: debug") at ./lib/zlog.h:84
#15 0x00007f6e21a451b2 in rpki_create_socket (_cache=0x55729149cc30) at bgpd/bgp_rpki.c:1337
#16 0x00007f6e2120e7b7 in tr_tcp_open (tr_socket=0x5572914d1520) at /home/lscalber/git/rtrlib/rtrlib/transport/tcp/tcp_transport.c:111
#17 0x00007f6e2120e212 in tr_open (socket=0x5572914b5e00) at /home/lscalber/git/rtrlib/rtrlib/transport/transport.c:16
#18 0x00007f6e2120faa2 in rtr_fsm_start (rtr_socket=0x557290e17180) at /home/lscalber/git/rtrlib/rtrlib/rtr/rtr.c:130
#19 0x00007f6e218b7ea7 in start_thread (arg=<optimized out>) at pthread_create.c:477
#20 0x00007f6e21527a2f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95