We would log "(null):0: Failed to parse system call, ignoring: rseq" from
log_syntax_internal() from log_syntax() from seccomp_parse_syscall_filter_full()
from seccomp_parse_syscall_filter() from config_parse_syscall_filter(),
when generating the built-in @default whitelist. Since it was not based on the
unit file, we would not pass a file name.
So let's make sure that log_syntax() does not print "(null)" pointer (which is
iffy and ugly), and use the unit name as fallback or nothing if both are missing.
In principle, one of the two should be always available, since why use log_syntax()
otherwise, but let's make things more resilient by guarding against this case too.
log_syntax() is called from a thousand places, and often in error path, so it's
hard to verify all callers.
It's not easy to implement such a combined operation race-freely since
dropping a subvolume will drop all its contents, including any
non-directories.
Hence, let's just not support this combination for now. Which isn't much
of a loss, since we never combine these flags anyway.
Some chattrs only work sensible if you set them right after opening a
file for create (think: FS_NOCOW_FL). Others only work when they are
applied when the file is fully written (think: FS_IMMUTABLE_FL). Let's
take that into account when copying files and applying a chattr to them.
When compiled with -DNDEBUG, we get warnings about set-but-unused variables.
In general, it's not something we care about, but since removing those
variables arguably makes the code nicer, let's just to it in this case.
It's a glibc-specific API, but supported on FreeBSD and musl too at
least, hence fairly common. This way we can reduce our calls to
realloc() as much as possible.
The loop around ttyname_r() makes it look like we use unbounded stack
allocations. We know that that paths have a maximum size, so let's simplify
the whole thing.
Replaces #12043.
Let's reduce the chance of failure: if we can't apply the chmod/chown
requested, check if it's applied anyway, and if so, supress the error.
This is even race-free since we operate on an O_PATH fd anyway.
socket_bind_to_ifindex() uses the the SO_BINDTOIFINDEX sockopt of kernel
5.0, with a fallback to SO_BINDTODEVICE on older kernels.
socket_bind_to_ifname() is a trivial wrapper around SO_BINDTODEVICE, the
only benefit of using it instead of SO_BINDTODEVICE directly is that it
determines the size of the interface name properly so that it also works
for unbinding. Moreover, it's an attempt to unify our invocations of the
sockopt with a size of strlen(ifname) rather than strlen(ifname)+1...
I had a test machine with ulimit -n set to 1073741816 through pam
("session required pam_limits.so set_all", which copies the limits from PID 1,
left over from testing of #10921).
test-execute would "hang" and then fail with a timeout when running
exec-inaccessiblepaths-proc.service. It turns out that the problem was in
close_all_fds(), which would go to the fallback path of doing close()
1073741813 times. Let's just fail if we hit this case. This only matters
for cases where both /proc is inaccessible, and the *soft* limit has been
raised.
(gdb) bt
#0 0x00007f7e2e73fdc8 in close () from target:/lib64/libc.so.6
#1 0x00007f7e2e42cdfd in close_nointr ()
from target:/home/zbyszek/src/systemd-work3/build-rawhide/src/shared/libsystemd-shared-241.so
#2 0x00007f7e2e42d525 in close_all_fds ()
from target:/home/zbyszek/src/systemd-work3/build-rawhide/src/shared/libsystemd-shared-241.so
#3 0x0000000000426e53 in exec_child ()
#4 0x0000000000429578 in exec_spawn ()
#5 0x00000000004ce1ab in service_spawn ()
#6 0x00000000004cff77 in service_enter_start ()
#7 0x00000000004d028f in service_enter_start_pre ()
#8 0x00000000004d16f2 in service_start ()
#9 0x00000000004568f4 in unit_start ()
#10 0x0000000000416987 in test ()
#11 0x0000000000417632 in test_exec_inaccessiblepaths ()
#12 0x0000000000419362 in run_tests ()
#13 0x0000000000419632 in main ()
