BBS:      TELESC.NET.BR
Assunto:  sbbs binary: Debian Linux AARCH64 sigfault or permission denied
De:       Deon George
Data:     Fri, 27 Feb 2026 14:25:08 -0800
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https://gitlab.synchro.net/main/sbbs/-/issues/685#note_8457

Dang, I was posting some testing updates, that I must not have submitted.

I did some AI searching too (because this is all foreign to me), and AI told me it was related to ASLR (whatever that is).

I tried `--cap-add=SYS_ADMIN` without success, and even `--security-opt seccomp=unconfined`, which it started then segfaulted again.

```
(gdb) bt
#0  0x0000400001418d6c in cleanup(int, int) [clone .constprop.0] () from /opt/sbbs/exec/libftpsrvr.so
#1  0x000040000141d9d4 in ftp_server () from /opt/sbbs/exec/libftpsrvr.so
#2  0x0000400001526648 in start_thread (arg=0x40000539aac0) at pthread_create.c:477
#3  0x0000400001621c9c in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:78
```

(This time ftp_server is the second line, a previous start it was mail_server.)

As I worked throught it with AI, it tells me:
```
If --security-opt seccomp=unconfined allows the application to proceed but it immediately segfaults, you have likely moved from a "permissions" problem to a "compatibility" or "memory mapping" problem. 

Likely Causes for the Segfault
Architecture Mismatch (Emulation Issues): [NO LIKELY? since its qemu aarch64 on aarch64].

GDB / Debugger Conflicts: If you are using a debugger like GDB, it calls personality(ADDR_NO_RANDOMIZE) to make memory addresses deterministic. If the application's internal memory management expects randomized addresses (or vice-versa), it can crash.

Invalid Memory Access: The application may be attempting to access a memory address that is only valid in a specific "personality" (like a 32-bit address space), but failing to map that memory correctly once the syscall succeeds. 
```

I tried the recommended `echo 0 | sudo tee /proc/sys/kernel/randomize_va_space` no change.

Looks like I might be stuck with `privileged` mode :( (But happy it looks like its working.)
--- SBBSecho 3.37-Linux
 * Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

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