| History log of /src/lib/libc/gen/pthread_atfork.c |
| Revision | | Date | Author | Comments |
| 1.28 |
| 06-May-2025 |
riastradh | libc: Sprinkle #ifdef _REENTRANT around thr_sigsetmask.
Workaround -- temporary, I hope -- for:
PR lib/59401: libc: thr_sigsetmask definition is incoherent
|
| 1.27 |
| 09-Apr-2025 |
kre | Redo pthread_atfork to avoid malloc()
Allow as many calls to pthread_atfork() as are needed, without
ever doing a single malloc() so it can be called as much as
needed in constructors, etc.
This is the implementation mooted some weeks ago - there
were some alternative suggestions for a different solution,
but none of them have eventuated, so until something else
happens, this will do.
I have been running with this for a while now, no issues
observed, though I am not much of a user of threaded
applications, or anything that really needs constructors.
Feel free to revert (or fix) this if something breaks.
|
| 1.26 |
| 04-Mar-2025 |
christos | Explain the situation better and allocate 16 instead of 3 for now to cover
the known cases (from kre@). Still needs to be fixed properly.
|
| 1.25 |
| 04-Mar-2025 |
riastradh | Revert __libc_atfork addition.
This reverts the following revisions:
lib/libc/gen/arc4random.c 1.40-41 (but not 1.42 which is independent)
lib/libc/gen/pthread_atfork.c 1.24
lib/libc/include/atfork.h 1.1
This additionally updates the comments in arc4random.c to reflect the
current state.
Requested by kre:
https://mail-index.netbsd.org/source-changes-d/2025/03/03/msg014388.html
Since the new symbol __libc_atfork has not been used outside libc,
this poses no ABI compatibility issues.
|
| 1.24 |
| 02-Mar-2025 |
riastradh | libc: New __libc_atfork.
This uses caller-provided storage for the callback queues.
Use it in arc4random(3) in order to avoid possible failure modes.
This is a private symbol, not designed for use outside NetBSD, and
the API is not intended to be stable (yet) -- I just took the
existing purely internal structure (struct atfork_callback) and
reused it for this API without changing any of the calling-side
logic. We could change it, e.g. to use a single structure per call,
to make the API a little less unwieldy, at the cost of
microscopically more storage and runtime for the users that don't use
all three callbacks; to be considered in a future change.
We might reasonably use __libc_atfork in libpthread for use in the
pthread_tsd_init constructor, in order to be confident it never
attempts malloc(3), but let's do that in a separate commit just in
case anything goes awry with that plan.
PR lib/59112: libpthread constructors use malloc
PR lib/59117: arc4random has some failure modes it shouldn't
|
| 1.23 |
| 01-Mar-2025 |
christos | simplify af_free() (from kre@)
|
| 1.22 |
| 01-Mar-2025 |
christos | keep a cache of 3 entries so that we don't have to call malloc(3) from
libpthread which can't call malloc from a constructor.
|
| 1.21 |
| 01-Mar-2025 |
christos | Revert for now. There has been a report that arc4random breaks with it,
and the tests for arc4random set RLIMIT_AS to 0 so that mmap fails.
|
| 1.20 |
| 28-Feb-2025 |
kre | Specify MAP_ANON, the default (MAP_FILE) with a fd == -1 makes no sense.
|
| 1.19 |
| 28-Feb-2025 |
christos | PR/59112: Martin Husemann: switch to using mmap instead of malloc
|
| 1.18 |
| 20-Jan-2024 |
christos | Catch up with all the lint warnings since exit on warning was disabled.
Disable 'missing header declaration' and 'nested extern' warnings for now.
|
| 1.17 |
| 13-Sep-2022 |
riastradh | pthread_atfork(3): Block signals during the call to pthread_atfork.
This doesn't affect the calls to the atfork handlers -- it only
protects access to the lists of handlers from interruption by a
signal, in case the signal handler calls fork(2).
|
| 1.16 |
| 31-May-2022 |
andvar | fix various typos in comments, documentation and messages.
|
| 1.15 |
| 15-May-2020 |
joerg | Hook up proper fork lock handling for malloc:
- lock all relevant mutexes just before fork
- unlock all mutexes just after fork in the parent
- full reinit non-spinlocks in the child
This is not using the normal pthread_atfork interface to ensure order of
operation, malloc is used as implementation detail too often.
|
| 1.14 |
| 19-Apr-2020 |
joerg | Rename __atomic_fork to __locked_fork and give it &errno as argument.
rtld and libc use different storage, so the initial version would
incorrectly report the failure reason for fork().
There is still a small race condition inside ld.elf_so as it doesn't use
thread-safe errno internally, but that's a more contained internal
issue.
|
| 1.13 |
| 16-Apr-2020 |
joerg | Introduce intermediate locking for fork, so that the dynamic linker is
in a consistent state. This most importantly avoids races between dlopen
and friends and fork, potentially resulting in dead locks in the child
when it itself tries to acquire locks.
|
| 1.12 |
| 01-Feb-2020 |
kamil | Revert previous
'git grep' breaks now.
|
| 1.11 |
| 01-Feb-2020 |
kamil | Switch atform allocations from malloc()+free() to mmap()+munmap()
This avoid bootstrapping malloc too early when libc+libpthread are not
ready. It is called through pthread__init() -> _pthread_atfork().
This also helps LLVM Leak Sanitizer to pacify false positive reports.
|
| 1.10 |
| 20-Jan-2015 |
christos | branches: 1.10.16; 1.10.18;
Fix non _REENTRANT build.
|
| 1.9 |
| 20-Mar-2012 |
matt | Use C89 definitions.
Remove use of __P
|
| 1.8 |
| 28-Apr-2008 |
martin | branches: 1.8.4; 1.8.8;
Remove clause 3 and 4 from TNF licenses
|
| 1.7 |
| 07-Mar-2008 |
ad | branches: 1.7.2;
Keep one builtin slot so that pthread initialization doesn't need to use
malloc().
|
| 1.6 |
| 14-Dec-2007 |
yamt | branches: 1.6.2;
fix indentation.
|
| 1.5 |
| 13-Sep-2005 |
christos | branches: 1.5.10;
compat core reorg.
|
| 1.4 |
| 01-Jun-2005 |
lukem | Ensure that we don't try to free random memory when another malloc fails,
by initializing newprepare, newparent, and newchild to NULL.
Detected by gcc -Wuninitialized.
|
| 1.3 |
| 21-Oct-2004 |
lukem | branches: 1.3.2;
minor KNF, making it easier to find where fork() is implemented
|
| 1.2 |
| 07-Apr-2003 |
nathanw | Oops, make the atfork queues static so they don't pollute the
namespace.
|
| 1.1 |
| 13-Feb-2003 |
nathanw | Implement pthread_atfork() (in libc, because the required threadlib
stub behavior is exactly the same as the usual behavior).
|
| 1.3.2.1 |
| 11-Jun-2005 |
tron | Pull up revision 1.4 (requested by lukem in ticket #394):
Ensure that we don't try to free random memory when another malloc fails,
by initializing newprepare, newparent, and newchild to NULL.
Detected by gcc -Wuninitialized.
|
| 1.5.10.2 |
| 23-Mar-2008 |
matt | sync with HEAD
|
| 1.5.10.1 |
| 09-Jan-2008 |
matt | sync with HEAD
|
| 1.6.2.1 |
| 24-Mar-2008 |
keiichi | sync with head.
|
| 1.7.2.1 |
| 18-May-2008 |
yamt | sync with head.
|
| 1.8.8.2 |
| 28-Apr-2008 |
martin | Remove clause 3 and 4 from TNF licenses
|
| 1.8.8.1 |
| 28-Apr-2008 |
martin | file pthread_atfork.c was added on branch christos-time_t on 2008-04-28 20:23:00 +0000
|
| 1.8.4.1 |
| 17-Apr-2012 |
yamt | sync with head
|
| 1.10.18.1 |
| 13-May-2020 |
martin | Pull up following revision(s) (requested by chs in ticket #907):
libexec/ld.elf_so/rtld.c: revision 1.205
libexec/ld.elf_so/rtld.h: revision 1.140
libexec/ld.elf_so/symbols.map: revision 1.3
libexec/ld.elf_so/symbols.map: revision 1.4
lib/libc/gen/pthread_atfork.c: revision 1.13
lib/libc/gen/pthread_atfork.c: revision 1.14
libexec/ld.elf_so/rtld.h: revision 1.139
libexec/ld.elf_so/rtld.c: revision 1.204
Introduce intermediate locking for fork, so that the dynamic linker is
in a consistent state. This most importantly avoids races between dlopen
and friends and fork, potentially resulting in dead locks in the child
when it itself tries to acquire locks.
Rename __atomic_fork to __locked_fork and give it &errno as argument.
rtld and libc use different storage, so the initial version would
incorrectly report the failure reason for fork().
There is still a small race condition inside ld.elf_so as it doesn't use
thread-safe errno internally, but that's a more contained internal
issue.
|
| 1.10.16.1 |
| 21-Apr-2020 |
martin | Sync with HEAD
|
