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* treewide: tighten variable scope in loops (#18372)Susant Sahani2021-01-271-6/+2
| | | | Also use _cleanup_free_ in one more place.
* sort-util: make cmp_int() generic, so that we can reuse it elsewhereLennart Poettering2020-12-171-4/+0
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* license: LGPL-2.1+ -> LGPL-2.1-or-laterYu Watanabe2020-11-091-1/+1
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* fd-util: port close_all_fds() to close_range()Lennart Poettering2020-10-141-0/+90
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* Merge pull request #17143 from keszybz/late-exec-resolution-altLennart Poettering2020-09-241-4/+2
|\ | | | | Late exec resolution (subset)
| * Add CLOSE_AND_REPLACE helperZbigniew Jędrzejewski-Szmek2020-09-181-4/+2
| | | | | | | | | | | | Similar to free_and_replace. I think this should be uppercase to make it clear that this is a macro. free_and_replace should probably be uppercased too.
* | basic: update fd_get_path() to use proc_mounted() helperLennart Poettering2020-09-231-5/+3
|/ | | | | | | | We use it pretty much everywhere else, hence use it here too. This also changes the error generated from EOPNOTSUPP to ENOSYS, to match the other cases where we do such a check. One user checked for EOPNOTSUPP which is updated to check for ENOSYS instead.
* tree-wide: fix spelling of "fallback"Zbigniew Jędrzejewski-Szmek2020-08-201-1/+1
| | | | | | Similarly to "setup" vs. "set up", "fallback" is a noun, and "fall back" is the verb. (This is pretty clear when we construct a sentence in the present continous: "we are falling back" not "we are fallbacking").
* fd-util: be more careful with fclose() errnosLennart Poettering2020-06-021-1/+4
| | | | This might fix #15859, a bug which I find very puzzling.
* tmpfiles: if we get ENOENT when opening /proc/self/fd/, check if /proc is ↵Lennart Poettering2020-04-231-3/+11
| | | | | | | | | | | | | | | | | | | | | | mounted let's return ENOSYS in that case, to make things a bit less confusng. Previously we'd just propagate ENOENT, which people might mistake as applying to the object being modified rather than /proc/ just not being there. Let's return ENOSYS instead, i.e. an error clearly indicating that some kernel API is not available. This hopefully should put people on a better track. Note that we only do the procfs check in the error path, which hopefully means it's the less likely path. We probably can add similar bits to more suitable codepaths dealing with /proc/self/fd, but for now, let's pick to the ones noticed in #14745. Fixes: #14745
* Add yet another tiny helper to manipulate flagsZbigniew Jędrzejewski-Szmek2020-04-101-10/+2
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* include missing_fcntl.h where neededAnita Zhang2019-11-071-0/+1
| | | | | | | f5947a5e925117c55b390460d592f57504277bf9 dropped missing.h and replaced with the more specific headers but did not add missing_fcntl.h in places that use O_TMPFILE. This is needed for some older versions of glibc.
* tree-wide: drop socket.h when socket-util.h is includedYu Watanabe2019-11-041-1/+0
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* tree-wide: drop missing.hYu Watanabe2019-10-311-1/+1
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* codespell: fix spelling errorsBen Boeckel2019-04-291-1/+1
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* basic/fd-util: refuse "infinite" loop in close_all_fds()Zbigniew Jędrzejewski-Szmek2019-03-151-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ()
* fd-util: rework how we determine highest possible fdLennart Poettering2019-01-181-11/+26
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* tree-wide: use c99 static for array size declarationsZbigniew Jędrzejewski-Szmek2019-01-041-1/+1
| | | | | | | | | | | | | | | | https://hamberg.no/erlend/posts/2013-02-18-static-array-indices.html This only works with clang, unfortunately gcc doesn't seem to implement the check (tested with gcc-8.2.1-5.fc29.x86_64). Simulated error: [2/3] Compiling C object 'systemd-nspawn@exe/src_nspawn_nspawn.c.o'. ../src/nspawn/nspawn.c:3179:45: warning: array argument is too small; contains 15 elements, callee requires at least 16 [-Warray-bounds] candidate = (uid_t) siphash24(arg_machine, strlen(arg_machine), hash_key); ^ ~~~~~~~~ ../src/basic/siphash24.h:24:64: note: callee declares array parameter as static here uint64_t siphash24(const void *in, size_t inlen, const uint8_t k[static 16]); ^~~~~~~~~~~~
* fd-util: Fix error handling in safe_fclosePaweł Szewczyk2018-12-061-1/+1
| | | | Function fclose_nointr returns negative value on error.
* util-lib: split out all temporary file related calls into tmpfiles-util.cLennart Poettering2018-12-021-0/+1
| | | | | | | | This splits out a bunch of functions from fileio.c that have to do with temporary files. Simply to make the header files a bit shorter, and to group things more nicely. No code changes, just some rearranging of source files.
* copy: support getting progress feedback from the various copy functionsLennart Poettering2018-11-261-1/+1
| | | | | | | | | This adds two optional functions that may be passed to the various copy functions. One is invoked whenever we start copying a new file object, the other while we copy file payload in each loop iteration. When the caller passes one or both they can get notifications about copy progress, for example to log where things are.
* fd-util: optimize fd_get_path() a bitLennart Poettering2018-10-251-12/+12
| | | | | | | | | | | | | | | | | | | journald calls fd_get_path() a lot (it probably shouldn't, there's some room for improvement there, but I'll leave that for another time), hence it's worth optimizing the call a bit, in particular as it's easy. Previously we'd open the dir /proc/self/fd/ first, before reading the symlink inside it. This means the whole function requires three system calls: open(), readlinkat(), close(). The reason for doing it this way is to distinguish the case when we see ENOENT because /proc is not mounted and the case when the fd doesn't exist. With this change we'll directly go for the readlink(), and only if that fails do an access() to see if /proc is mounted at all. This optimizes the common case (where the fd is valid and /proc mounted), in favour of the uncommon case (where the fd doesn#t exist or /proc is not mounted).
* fd-util: accept that kcmp might fail with EPERM/EACCESSjoerd Simons2018-08-291-1/+1
| | | | | In a container the kcmp call might well be blocked; Accept that and fall back to fstat in that case.
* tree-wide: remove Lennart's copyright linesLennart Poettering2018-06-141-3/+0
| | | | | | | | | | | These lines are generally out-of-date, incomplete and unnecessary. With SPDX and git repository much more accurate and fine grained information about licensing and authorship is available, hence let's drop the per-file copyright notice. Of course, removing copyright lines of others is problematic, hence this commit only removes my own lines and leaves all others untouched. It might be nicer if sooner or later those could go away too, making git the only and accurate source of authorship information.
* tree-wide: drop 'This file is part of systemd' blurbLennart Poettering2018-06-141-2/+0
| | | | | | | | | | | | | | | | This part of the copyright blurb stems from the GPL use recommendations: https://www.gnu.org/licenses/gpl-howto.en.html The concept appears to originate in times where version control was per file, instead of per tree, and was a way to glue the files together. Ultimately, we nowadays don't live in that world anymore, and this information is entirely useless anyway, as people are very welcome to copy these files into any projects they like, and they shouldn't have to change bits that are part of our copyright header for that. hence, let's just get rid of this old cruft, and shorten our codebase a bit.
* main: split out reading of /proc/sys/fs/nr_open into its own functionLennart Poettering2018-06-061-0/+24
| | | | | This doesn't really reduce the code size over all, but it does make main.c shorter and more readable, and that's always a good thing.
* tree-wide: drop unused variablesYu Watanabe2018-05-251-1/+0
| | | | Follow-ups for #8620.
* fd-util: add new helper call fd_duplicate_data_fd()Lennart Poettering2018-05-241-0/+199
| | | | | | | | | | | | This call creates an fd from another fd containing the same data. Specifically, repeated read() on the returned fd should return the same data as the original fd. This call is useful when we want to copy data out of disk images and suchlike, and want to be pass fds with the data around without having to keep the disk image continously mounted. The implementation tries to be somewhat smart and tries to prefer memfds/pipes over files in /tmp or /var/tmp based on the size of the data, but has appropropriate fallbacks in place.
* basic: be more careful when closing fds based on RLIMIT_NOFILELennart Poettering2018-05-171-4/+11
| | | | | Let's make sure we properly handle cases where RLIMIT_NOFILE is set to infinity, zero or values outside of the "int" range.
* tree-wide: be more careful with the type of array sizesLennart Poettering2018-04-271-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously we were a bit sloppy with the index and size types of arrays, we'd regularly use unsigned. While I don't think this ever resulted in real issues I think we should be more careful there and follow a stricter regime: unless there's a strong reason not to use size_t for array sizes and indexes, size_t it should be. Any allocations we do ultimately will use size_t anyway, and converting forth and back between unsigned and size_t will always be a source of problems. Note that on 32bit machines "unsigned" and "size_t" are equivalent, and on 64bit machines our arrays shouldn't grow that large anyway, and if they do we have a problem, however that kind of overly large allocation we have protections for usually, but for overflows we do not have that so much, hence let's add it. So yeah, it's a story of the current code being already "good enough", but I think some extra type hygiene is better. This patch tries to be comprehensive, but it probably isn't and I missed a few cases. But I guess we can cover that later as we notice it. Among smaller fixes, this changes: 1. strv_length()' return type becomes size_t 2. the unit file changes array size becomes size_t 3. DNS answer and query array sizes become size_t Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=76745
* tree-wide: drop license boilerplateZbigniew Jędrzejewski-Szmek2018-04-061-13/+0
| | | | | | | | | | Files which are installed as-is (any .service and other unit files, .conf files, .policy files, etc), are left as is. My assumption is that SPDX identifiers are not yet that well known, so it's better to retain the extended header to avoid any doubt. I also kept any copyright lines. We can probably remove them, but it'd nice to obtain explicit acks from all involved authors before doing that.
* fd-util: introduce fd_reopen() helper for reopening an fdLennart Poettering2018-03-291-7/+20
| | | | | | We have the same code for this in place at various locations, let's unify that. Also, let's repurpose test-fs-util.c as a test for this new helper cal..
* macro: introduce new TAKE_FD() macroLennart Poettering2018-03-221-8/+2
| | | | | | | This is similar to TAKE_PTR() but operates on file descriptors, and thus assigns -1 to the fd parameter after returning it. Removes 60 lines from our codebase. Pretty good too I think.
* basic/fs-util: skip fsync_directory_of_file() if /proc/self/fd/ is not ↵Zbigniew Jędrzejewski-Szmek2018-03-201-4/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | available (#8386) When systemd is running under lorax (in Fedora compose process), it'd think that it failed to write /etc/machine-id, even though the write succeeded, because fsync_directory_of_file() would fail, because /proc/self/fd/ is not available. fsync_directory_of_file() is mostly an additional safety net, so I think it's best to just silently ignore the error. Strace of pid1: 35791 stat("/etc", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 35791 openat(AT_FDCWD, "/etc/machine-id", O_RDWR|O_CREAT|O_NOCTTY|O_CLOEXEC, 0444) = 3 35791 umask(022) = 000 35791 read(3, "", 38) = 0 35791 openat(AT_FDCWD, "/var/lib/dbus/machine-id", O_RDONLY|O_NOCTTY|O_NOFOLLOW|O_CLOEXEC) = -1 ENOENT (No such file o r directory) 35791 openat(AT_FDCWD, "/sys/class/dmi/id/product_name", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) 35791 openat(AT_FDCWD, "/sys/class/dmi/id/sys_vendor", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) 35791 openat(AT_FDCWD, "/sys/class/dmi/id/board_vendor", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) 35791 openat(AT_FDCWD, "/sys/class/dmi/id/bios_vendor", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) 35791 access("/proc/xen", F_OK) = -1 ENOENT (No such file or directory) 35791 openat(AT_FDCWD, "/sys/hypervisor/type", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) 35791 openat(AT_FDCWD, "/proc/cpuinfo", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) 35791 getrandom("\xb8\x82\xed\xd4\x35\x11\xd0\xeb\xa6\x79\xd7\x31\x6e\x7b\x99\xce", 16, GRND_NONBLOCK) = 16 35791 writev(2, [{iov_base="Initializing machine ID from random generator.", iov_len=46}, {iov_base="\n", iov_len=1}], 2) = 47 35791 lseek(3, 0, SEEK_SET) = 0 35791 ftruncate(3, 0) = 0 35791 write(3, "b882edd4351140eba679d7316e7b99ce\n", 33) = 33 35791 fsync(3) = 0 35791 fstat(3, {st_mode=S_IFREG|0444, st_size=33, ...}) = 0 35791 readlinkat(AT_FDCWD, "/proc/self/fd/3", 0x564df8c694c0, 99) = -1 ENOENT (No such file or directory) 35791 close(3) = 0 35791 umask(022) = 022 35791 openat(AT_FDCWD, "/run/machine-id", O_WRONLY|O_CREAT|O_NOCTTY|O_TRUNC|O_CLOEXEC, 0444) = 3 35791 write(3, "b882edd4351140eba679d7316e7b99ce\n", 33) = 33 35791 close(3) = 0 35791 umask(022) = 022 35791 mount("/run/machine-id", "/etc/machine-id", NULL, MS_BIND, NULL) = 0 35791 writev(2, [{iov_base="Installed transient /etc/machine-id file.", iov_len=41}, {iov_base="\n", iov_len=1}], 2) = 42 35791 mount(NULL, "/etc/machine-id", NULL, MS_RDONLY|MS_REMOUNT|MS_BIND, NULL) = 0 https://bugzilla.redhat.com/show_bug.cgi?id=1552843
* fd-util: drop stdio_unset_cloexec(), it's not used anymoreLennart Poettering2018-03-021-6/+0
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* fd-util: add new call rearrange_stdio()Lennart Poettering2018-03-021-0/+115
| | | | | | | | | | | | | | | | | | | Quite often we need to set up a number of fds as stdin/stdout/stderr of a process we are about to start. Add a generic implementation for a routine doing that that takes care to do so properly: 1. Can handle the case where stdin/stdout/stderr where previously closed, and the fds to set as stdin/stdout/stderr hence likely in the 0..2 range. handling this properly is nasty, since we need to first move the fds out of this range in order to later move them back in, to make things fully robust. 2. Can optionally open /dev/null in case for one or more of the fds, in a smart way, sharing the open file if possible between multiple of the fds. 3. Guarantees that O_CLOEXEC is not set on the three fds, even if the fds already were in the 0..2 range and hence possibly weren't moved.
* fd-util: move certain fds above fd #2 (#8129)Lennart Poettering2018-02-091-0/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds some paranoia code that moves some of the fds we allocate for longer periods of times to fds > 2 if they are allocated below this boundary. This is a paranoid safety thing, in order to avoid that external code might end up erroneously use our fds under the assumption they were valid stdin/stdout/stderr. Think: some app closes stdin/stdout/stderr and then invokes 'fprintf(stderr, …' which causes writes on our fds. This both adds the helper to do the moving as well as ports over a number of users to this new logic. Since we don't want to litter all our code with invocations of this I tried to strictly focus on fds we keep open for long periods of times only and only in code that is frequently loaded into foreign programs (under the assumptions that in our own codebase we are smart enough to always keep stdin/stdout/stderr allocated to avoid this pitfall). Specifically this means all code used by NSS and our sd-xyz API: 1. our logging APIs 2. sd-event 3. sd-bus 4. sd-resolve 5. sd-netlink This changed was inspired by this: https://github.com/systemd/systemd/issues/8075#issuecomment-363689755 This shows that apparently IRL there are programs that do close stdin/stdout/stderr, and we should accomodate for that. Note that this won't fix any bugs, this just makes sure that buggy programs are less likely to interfere with out own code.
* fd-util: use close_nointr() return value instead of errnoLennart Poettering2017-12-251-9/+8
| | | | | Our own calls return errors in their return values, hence use that rather than errno when checking errors.
* fd-util: add some (void) castsLennart Poettering2017-12-251-3/+3
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* tree-wide: make use of new STRLEN() macro everywhere (#7639)Lennart Poettering2017-12-141-1/+1
| | | | | Let's employ coccinelle to do this for us. Follow-up for #7625.
* tree-wide: use STRLEN() to allocate buffer of constant sizeThomas Haller2017-12-131-1/+1
| | | | | | | | | | Using strlen() to declare a buffer results in a variable-length array, even if the compiler likely optimizes it to be a compile time constant. When building with -Wvla, certain versions of gcc complain about such buffers. Compiling with -Wvla has the advantage of preventing variably length array, which defeat static asserts that are implemented by declaring an array of negative length.
* Merge pull request #7198 from poettering/stdin-stdoutLennart Poettering2017-11-191-0/+201
|\ | | | | Add StandardInput=data, StandardInput=file:... and more
| * fd-util: add new acquire_data_fd() API helperLennart Poettering2017-11-171-0/+157
| | | | | | | | | | | | | | | | | | All this function does is place some data in an in-memory read-only fd, that may be read back to get the original data back. Doing this in a way that works everywhere, given the different kernels we support as well as different privilege levels is surprisingly complex.
| * fd-util: add new helper move_fd() and make use of itLennart Poettering2017-11-171-0/+44
| | | | | | | | | | | | | | We are using the same pattern at various places: call dup2() on an fd, and close the old fd, usually in combination with some O_CLOEXEC fiddling. Let's add a little helper for this, and port a few obvious cases over.
* | Add SPDX license identifiers to source files under the LGPLZbigniew Jędrzejewski-Szmek2017-11-191-0/+1
|/ | | | | This follows what the kernel is doing, c.f. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5fd54ace4721fc5ce2bb5aef6318fcf17f421460.
* tree-wide: make use of getpid_cached() wherever we canLennart Poettering2017-07-201-1/+2
| | | | | | | This moves pretty much all uses of getpid() over to getpid_raw(). I didn't specifically check whether the optimization is worth it for each replacement, but in order to keep things simple and systematic I switched over everything at once.
* tree-wide: replace all readdir cycles with FOREACH_DIRENT{,_ALL} (#4853)Reverend Homer2016-12-091-4/+2
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* basic/fd-util: introduce stdio_unset_cloexec() functionAlexander Kuleshov2016-07-021-0/+6
| | | | | | | | | | | There are some places in the systemd which are use the same pattern: fd_cloexec(STDIN_FILENO, false); fd_cloexec(STDOUT_FILENO, false); fd_cloexec(STDERR_FILENO, false); to unset CLOEXEC for standard file descriptors. This patch introduces the stdio_unset_cloexec() function to hide this and make code cleaner.
* journal: when creating a new journal file, fsync() the directory it is ↵Lennart Poettering2016-04-291-1/+7
| | | | | | created in too Fixes: #2831
* tree-wide: rename hidden_file to hidden_or_backup_file and optimizeZbigniew Jędrzejewski-Szmek2016-04-281-1/+1
| | | | | | | | | | | In standard linux parlance, "hidden" usually means that the file name starts with ".", and nothing else. Rename the function to convey what the function does better to casual readers. Stop exposing hidden_file_allow_backup which is rather ugly and rewrite hidden_file to extract the suffix first. Note that hidden_file_allow_backup excluded files with "~" at the end, which is quite confusing. Let's get rid of it before it gets used in the wrong place.
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