open https://gitlab.synchro.net/main/sbbs/-/issues/1131

Today I noticed a coredump from 16th

```
Core was generated by `/sbbs/exec/sbbs s! d'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x0000793ebc20d4e5 in ?? ()
[Current thread is 1 (Thread 0x793f5b1ff6c0 (LWP 14499))]
(gdb) bt
#0 0x0000793ebc20d4e5 in ?? ()
#1 0x0000793f5b1f8bf0 in ?? ()
#2 0x0000793fc0d0c442 in js::ExecuteTrace (state=..., f=0x793f68e50f70, tm=0x79015b1f8940,
cx=0x793fc0d6b4e4 <JSObject::extend(JSContext*, js::Shape const*, bool)+90>) at jstracer.cpp:6568
#3 js::ExecuteTree (cx=0x793f6dda42e0, tm=0xfffaf93f6dda42e0, f=0x793f69cdeeb0,
inlineCallCount=<error reading variable: Cannot access memory at address 0x6ddc8d80>,
innermostNestedGuardp=0x793f5b1f89e0, lrp=0x793f5b1f88a0) at jstracer.cpp:6674
Backtrace stopped: frame did not save the PC
```

Additionally, dmesg has

```
[Thu Apr 16 04:11:53 2026] show_signal_msg: 151 callbacks suppressed
[Thu Apr 16 04:11:53 2026] sbbs/jsService[14499]: segfault at 793ebc20d4e5 ip 0000793ebc20d4e5 sp 0000793f5b1f8a30 error 14 likely on CPU 0 (core 0, socket 0)
[Thu Apr 16 04:11:53 2026] Code: Unable to access opcode bytes at 0x793ebc20d4bb.

```

It appears someone was trying to download a large number of messages via IMAP

```
Apr 16 04:11:52 bbs synchronet: srvc 0054 IMAPv4-TLS Send: * 156: 7579 FETCH (RFC822.SIZE 1536 UID 23250 BODY[HEADER.FIELDS (Message-ID)] {68}#015#012Message-ID: <698AF3AE.23250.agoranetagn_hub@endofthelinebbs.com>#015#012#015#012 FLAGS ())
Apr 16 04:11:52 bbs synchronet: srvc 0054 IMAPv4-TLS Send: * 156: 7580 FETCH (RFC822.SIZE 1946 UID 23251 BODY[HEADER.FIELDS (Message-ID)] {68}#015#012Message-ID: <698C3003.23251.agoranetagn_hub@endofthelinebbs.com>#015#012#015#012 FLAGS ())
Apr 16 04:11:52 bbs synchronet: srvc 0054 IMAPv4-TLS Send: * 156: 7581 FETCH (RFC822.SIZE 6558 UID 23252 BODY[HEADER.FIELDS (Message-ID)] {68}#015#012Message-ID: <698C3003.23252.agoranetagn_hub@endofthelinebbs.com>#015#012#015#012 FLAGS ())
Apr 16 04:11:53 bbs synchronet: srvc 0054 IMAPv4-TLS Send: * 157: 7582 FETCH (RFC822.SIZE 13914 UID 23253 BODY[HEADER.FIELDS (Message-ID)] {68}#015#012Message-ID: <698C3003.23253.agoranetagn_hub@endofthelinebbs.com>#015#012#015#012 FLAGS ())
Apr 16 04:12:28 bbs synchronet: srvc Synchronet Services Version 3.21f Debug ```
--- SBBSecho 3.37-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

https://gitlab.synchro.net/main/sbbs/-/issues/1131#note_8837

This is a bt full in case it helps

```
Core was generated by `/sbbs/exec/sbbs s! d'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x0000793ebc20d4e5 in ?? ()
[Current thread is 1 (Thread 0x793f5b1ff6c0 (LWP 14499))]
(gdb) bt full
#0 0x0000793ebc20d4e5 in ?? ()
No symbol table info available.
#1 0x0000793f5b1f8bf0 in ?? ()
No symbol table info available.
#2 0x0000793fc0d0c442 in js::ExecuteTrace (state=..., f=0x793f68e50f70, tm=0x79015b1f8940,
cx=0x793fc0d6b4e4 <JSObject::extend(JSContext*, js::Shape const*, bool)+90>) at jstracer.cpp:6568
u = {code = 0x793f5b1f89e0 "\340B\332m?\371\372\377\340B\332m?y", func = 0x793f5b1f89e0}
rec = 0x793f69cdeeb0
#3 js::ExecuteTree (cx=0x793f6dda42e0, tm=0xfffaf93f6dda42e0, f=0x793f69cdeeb0,
inlineCallCount=<error reading variable: Cannot access memory at address 0x6ddc8d80>,
innermostNestedGuardp=0x793f5b1f89e0, lrp=0x793f5b1f88a0) at jstracer.cpp:6674
state = {cx = 0x793f6ddbfea0, traceMonitor = 0x793f69cdeeb0, stackBase = 0x100000000, sp = 0xa2f9aaae69bc0300,
eos = 0x793f5b1f89b0, callstackBase = 0x793fc0d6ad91 <js_AddAtomProperty(JSContext*, JSObject*, js::Shape*)+49>,
sor = 0x793f6dda42e0, rp = 0x793f68e50f70, eor = 0x793f6ddbfea0, lastTreeExitGuard = 0x793f69cdeeb0,
lastTreeCallGuard = 0x793f5b1f8a30, rpAtLastTreeCall = 0x793fb45b07ea, outermostTreeExitGuard = 0x793f5b1f89f0,
outermostTree = 0x793f69cdeeb0, inlineCallCountp = 0xfffbf93f5b4de840,
innermostNestedGuardp = 0xfffbf93f6ddc8d80, innermost = 0xfffaf93f6dda42e0, startTime = 133313332921056,
prev = 0x793f6ddbfea0, builtinStatus = 1843020224, deepBailSp = 0x3ffa78, nativeVpLen = 1528793888,
nativeVp = 0x793f6c200590}
stack = 0x793f5b1f89e8
global = 0x793f68e50f70
globalObj = 0x793f5b1f8910
ngslots = 31039
gslots = 0x793fc0c94c62 <JSObject::updateFlags(js::Shape const*, bool)+118>
lr = 0x793f6ddbfea0
ok = 105
iters = 133313333034656
Backtrace stopped: frame did not save the PC
```
--- SBBSecho 3.37-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)