Implement directives `NoExecPaths=` and `ExecPaths=` to control `MS_NOEXEC`
mount flag for the file system tree. This can be used to implement file system
W^X policies, and for example with allow-listing mode (NoExecPaths=/) a
compromised service would not be able to execute a shell, if that was not
explicitly allowed.
Example:
[Service]
NoExecPaths=/
ExecPaths=/usr/bin/daemon /usr/lib64 /usr/lib
Closes: #17942.
Upstream uses .text, but this is rather unusual. Let's use .txt as the usual
suffix for text files. This tells various editors and such that the file should
be treated as plain text. I also want to a script to summarize license status,
and having an easy-to-recognize suffix makes this easier.
Even though many of those scripts are very simple, it is easier to include
the header than to try to say whether each of those files is trivial enough
not to require one.
We reject all openat2() calls because it is currently not possible to
inspect its flags parameter via seccomp.
Fallback code is more likely to look for ENOSYS than EPERM.
Before this commit, udevd is built with LOG_REALM=LOG_REALM_UDEV.
However, log level specified by e.g. environment variable or kernel
command line option are also passed to LOG_REALM_SYSTEMD. So, the
maximum log level for the two realms are always equivalent, and it is
not necessary to specify the build option. Hence drop it.
This adds a new function table_print_with_pager() which is a wrapper
around table_print_json()/table_print() but spawns a pager first, if
that's enabled, and optionally turns off the header line of the table.
This addresses the fact that many of our tools actually keep doing very
this very similar stuff, over and over again. Let's unify this in one
place.
@keszybz's right on
https://github.com/systemd/systemd/pull/18248#issuecomment-760798473:
swapping out the userdata pointer of a live varlink connection is iffy.
Let's fix this by making the userdata inheritance from VarlinkServer
object to the Varlink connection object optional: we want it for most
cases, but not all, i.e. all those cases where the calls implemented as
varlink methods are stateless and can be answered synchronously. For the
other cases (i.e. where we want per-connection objects that wrap the
asynchronous operation as it goes on) let's not do such inheritance but
initialize the userdata pointer only once we have it. THis means the
original manager object must be manually retrieved from the
VarlinkServer object, which in turn needs to be requested from the
Varlink connection object.
The userdata inheritance is now controlled by the
VARLINK_INHERIT_USERDATA flag passed at VarlinkServer construction.
Alternative-to: #18248
Apparently SELinux inserts control data into AF_UNIX datagrams where we
don't expect it, thus miscalculating the control data. This looks like
something to fix in SELinux, but we still should handle this gracefully
and just drop the offending datagram and continue.
recvmsg_safe() actually already drops the datagram, it's just a matter
of actually ignoring EXFULL (which it generates if control data is too
large) in the right places.
This does this wherever an AF_UNIX/SOCK_DGRAM socket is used with
recvmsg_safe() that is not just internal communication.
Fixes: #17795
Follow-up for: 3691bcf3c5
The nft set backend doesn't support network masks, it works with
ranges. Inputs like dead::/64 thus need to be translated to two
'start' and 'end' elements.
The 'start' element is the first element in the range (i.e., dead::).
The 'stop' element is the first element *past* the range, (dead:0:0100::
in the example).
This adds a few test cases.
In case external entity wiped the ruleset, we need to clear the
'previous' address -- its already gone.
This prevents the transaction from succeeding: the delete operation fails.
closely mirrors the existing ipv4 ruleset:
table ip6 io.systemd.nat {
set masq_saddr {
type ipv6_addr
flags interval
}
map map_port_ipport {
type inet_proto . inet_service : ipv6_addr . inet_service
}
chain prerouting {
type nat hook prerouting priority dstnat + 1; policy accept;
fib daddr type local dnat ip6 addr . port to meta l4proto . th dport map @map_port_ipport
}
chain output {
type nat hook output priority -99; policy accept;
ip6 daddr != ::1 oif "lo" dnat ip6 addr . port to meta l4proto . th dport map @map_port_ipport
}
chain postrouting {
type nat hook postrouting priority srcnat + 1; policy accept;
ip6 saddr @masq_saddr masquerade
}
}
Only difference is the use of ipv6 addresses instead of ipv4 ones.
Currently has no effect: all in-tree callers pass AF_INET exclusively.
Followup patches will make nspawn expose ipv6 too and rework
IPMasquerade option to support both/v4/v6.
DNS_HOSTNAME_MAX is used by sd-resolve, but it was defined in
src/shared/dns-domain.h. The library libsystemd should be independent
of source files under src/shared.
offline-passwd.[ch] are only used by systemd-tmpfiles and the relevant
test. And are not included in libshared. So, it is not suitable to
located under src/shared.
machinectl fails since 21935150a0 as it's now
mounting onto a file descriptor in a target namespace, without joining the
target's PID namespace.
Note that it's not enough to setns CLONE_NEWPID, but a double-fork is required
as well, as implemented by namespace_fork().
Add a test case to TEST-13-NSPAWN to cover this use case.
This adds the support for veritytab.
The veritytab file contains at most five fields, the first four are
mandatory, the last one is optional:
- The first field contains the name of the resulting verity volume; its
block device is set up /dev/mapper/</filename>.
- The second field contains a path to the underlying block data device,
or a specification of a block device via UUID= followed by the UUID.
- The third field contains a path to the underlying block hash device,
or a specification of a block device via UUID= followed by the UUID.
- The fourth field is the roothash in hexadecimal.
- The fifth field, if present, is a comma-delimited list of options.
The following options are recognized only: ignore-corruption,
restart-on-corruption, panic-on-corruption, ignore-zero-blocks,
check-at-most-once and root-hash-signature. The others options will
be implemented later.
Also, this adds support for the new kernel verity command line boolean
option "veritytab" which enables the read for veritytab, and the new
environment variable SYSTEMD_VERITYTAB which sets the path to the file
veritytab to read.
This adds the ability to specify truncate:PATH for StandardOutput= and
StandardError=, similar to the existing append:PATH. The code is mostly
copied from the related append: code. Fixes#8983.
Anita Zhang
Yu Watanabe
Topi Miettinen
Zbigniew Jędrzejewski-Szmek
Mike Gilbert
Lennart Poettering
Luca Boccassi
Florian Westphal
Susant Sahani
Luca Boccassi
Gaël PORTAY
Lucas Werkmeister