Commit graph

62 commits

Author SHA1 Message Date
Stefano Brivio
33b1bdd079 seccomp: Add a number of alternate and per-arch syscalls
Depending on the C library, but not necessarily in all the
functions we use, statx() might be used instead of stat(),
getdents() instead of getdents64(), readlinkat() instead of
readlink(), openat() instead of open().

On aarch64, it's clone() and not fork(), and dup3() instead of
dup2() -- just allow the existing alternative instead of dealing
with per-arch selections.

Since glibc commit 9a7565403758 ("posix: Consolidate fork
implementation"), we need to allow set_robust_list() for
fork()/clone(), even in a single-threaded context.

On some architectures, epoll_pwait() is provided instead of
epoll_wait(), but never both. Same with newfstat() and
fstat(), sigreturn() and rt_sigreturn(), getdents64() and
getdents(), readlink() and readlinkat(), unlink() and
unlinkat(), whereas pipe() might not be available, but
pipe2() always is, exclusively or not.

Seen on Fedora 34: newfstatat() is used on top of fstat().

syslog() is an actual system call on some glibc/arch combinations,
instead of a connect()/send() implementation.

On ppc64 and ppc64le, _llseek(), recv(), send() and getuid()
are used. For ppc64 only: ugetrlimit() for the getrlimit()
implementation, plus sigreturn() and fcntl64().

On s390x, additionally, we need to allow socketcall() (on top
of socket()), and sigreturn() also for passt (not just for
pasta).

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-01-26 16:30:59 +01:00
Stefano Brivio
34872fadec pasta: Check for zero d_reclen returned by getdents64() syscall
Seen on PPC with some older kernel versions: we seemingly have bytes
left to read from the returned array of dirent structs, but d_reclen
is zero: this, and all the subsequent entries, are not valid.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-01-26 16:30:59 +01:00
Stefano Brivio
4c7304db85 conf, pasta: Explicitly pass CLONE_{NEWUSER,NEWNET} to setns()
Only allow the intended types of namespaces to be joined via setns()
as a defensive measure.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-01-26 16:30:59 +01:00
Stefano Brivio
b93c2c1713 passt: Drop <linux/ipv6.h> include, carry own ipv6hdr and opt_hdr definitions
This is the only remaining Linux-specific include -- drop it to avoid
clang-tidy warnings and to make code more portable.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-01-26 07:57:09 +01:00
Stefano Brivio
627e18fa8a passt: Add cppcheck target, test, and address resulting warnings
...mostly false positives, but a number of very relevant ones too,
in tcp_get_sndbuf(), tcp_conn_from_tap(), and siphash PREAMBLE().

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-21 09:41:13 +02:00
Stefano Brivio
dd942eaa48 passt: Fix build with gcc 7, use std=c99, enable some more Clang checkers
Unions and structs, you all have names now.

Take the chance to enable bugprone-reserved-identifier,
cert-dcl37-c, and cert-dcl51-cpp checkers in clang-tidy.

Provide a ffsl() weak declaration using gcc built-in.

Start reordering includes, but that's not enough for the
llvm-include-order checker yet.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-21 04:26:08 +02:00
Stefano Brivio
12cfa6444c passt: Add clang-tidy Makefile target and test, take care of warnings
Most are just about style and form, but a few were actually
serious mistakes (NDP-related).

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-20 08:34:22 +02:00
Stefano Brivio
1a563a0cbd passt: Address gcc 11 warnings
A mix of unchecked return values, a missing permission mask for
open(2) with O_CREAT, and some false positives from
-Wstringop-overflow and -Wmaybe-uninitialized.

Reported-by: Martin Hauke <mardnh@gmx.de>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-20 08:29:30 +02:00
Stefano Brivio
17600d6d6e netlink, conf: Actually get prefix/mask length
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-19 09:01:27 +02:00
Stefano Brivio
364cc313ea pasta: Allow nanosleep(2) and clock_nanosleep(2) syscalls too
...we need those to wait for terminating processes in the namespace.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-14 21:48:44 +02:00
Stefano Brivio
3c6d24dd30 netlink, pasta: Configure MTU of tap interface on --config-net
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-14 13:20:34 +02:00
Stefano Brivio
32d07f5e59 passt, pasta: Completely avoid dynamic memory allocation
Replace libc functions that might dynamically allocate memory with own
implementations or wrappers.

Drop brk(2) from list of allowed syscalls in seccomp profile.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2021-10-14 13:16:03 +02:00