seccomp: passthrough uretprobe systemcall without filtering
Summary
seccomp: passthrough uretprobe systemcall without filtering
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
seccomp: passthrough uretprobe systemcall without filtering
When attaching uretprobes to processes running inside docker, the attached
process is segfaulted when encountering the retprobe.
The reason is that now that uretprobe is a system call the default seccomp
filters in docker block it as they only allow a specific set of known
syscalls. This is true for other userspace applications which use seccomp
to control their syscall surface.
Since uretprobe is a "kernel implementation detail" system call which is
not used by userspace application code directly, it is impractical and
there's very little point in forcing all userspace applications to
explicitly allow it in order to avoid crashing tracked processes.
Pass this systemcall through seccomp without depending on configuration.
Note: uretprobe is currently only x86_64 and isn't expected to ever be
supported in i386.
[kees: minimized changes for easier backporting, tweaked commit log]
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2025-21834 linux-lts Fixed in: 6.12.41-r0
- Debian DEBIAN-CVE-2025-21834 linux Fixed in: 6.12.15-1
References
- advisory github.com
- advisory nvd.nist.gov
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org