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Florian Weimer 60f8062425 nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161]
Commit 27761a1042 ("Refactor atfork
handlers") introduced a lock, atfork_lock, around fork handler list
accesses.  It turns out that this lock occasionally results in
self-deadlocks in malloc/tst-mallocfork2:

(gdb) bt
#0  __lll_lock_wait_private ()
    at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:63
#1  0x00007f160c6f927a in __run_fork_handlers (who=(unknown: 209394016),
    who@entry=atfork_run_prepare) at register-atfork.c:116
#2  0x00007f160c6b7897 in __libc_fork () at ../sysdeps/nptl/fork.c:58
#3  0x00000000004027d6 in sigusr1_handler (signo=<optimized out>)
    at tst-mallocfork2.c:80
#4  sigusr1_handler (signo=<optimized out>) at tst-mallocfork2.c:64
#5  <signal handler called>
#6  0x00007f160c6f92e4 in __run_fork_handlers (who=who@entry=atfork_run_parent)
    at register-atfork.c:136
#7  0x00007f160c6b79a2 in __libc_fork () at ../sysdeps/nptl/fork.c:152
#8  0x0000000000402567 in do_test () at tst-mallocfork2.c:156
#9  0x0000000000402dd2 in support_test_main (argc=1, argv=0x7ffc81ef1ab0,
    config=config@entry=0x7ffc81ef1970) at support_test_main.c:350
#10 0x0000000000402362 in main (argc=<optimized out>, argv=<optimized out>)
    at ../support/test-driver.c:168

If no locking happens in the single-threaded case (where fork is
expected to be async-signal-safe), this deadlock is avoided.
(pthread_atfork is not required to be async-signal-safe, so a fork
call from a signal handler interrupting pthread_atfork is not
a problem.)

(cherry picked from commit 669ff911e2)
2019-02-08 12:55:21 +01:00
ChangeLog.old
argp Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
assert Fix uninitialized variable in assert_perror (bug 22761) 2018-02-05 11:06:15 +01:00
benchtests benchtests: improve argument parsing through argparse library 2018-07-19 14:53:37 -05:00
bits Add <bits/indirect-return.h> 2018-07-24 07:55:47 -07:00
catgets intl/tst-gettext: fix failure with newest msgfmt 2018-02-18 18:16:05 +01:00
conform conform: XFAIL siginfo_t si_band test on sparc64 2018-10-26 09:19:40 +02:00
crypt New configure option --disable-crypt. 2018-06-29 16:53:47 +02:00
csu Build csu/elf-init.c and csu/static-reloc.c with stack protector 2018-07-05 22:57:45 +02:00
ctype Use libc_hidden_* for tolower, toupper (bug 15105). 2018-02-23 13:54:53 +00:00
debug Compile debug/stack_chk_fail_local.c with stack protector 2018-07-05 19:28:35 +02:00
dirent Consolidate alphasort{64} and versionsort{64} implementation 2018-04-23 17:35:16 -03:00
dlfcn malloc: tcache double free check 2018-11-28 15:45:42 -05:00
elf RISC-V: properly terminate call chain (bug 23125) 2018-12-15 21:57:43 +01:00
gmon Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
gnulib Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
grp [BZ #20271] Add newlines in __libc_fatal calls. 2018-11-09 10:17:07 -05:00
gshadow Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
hesiod Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
htl hurd: Add missing symbols for proper libc_get/setspecific 2018-08-08 02:17:39 +02:00
hurd hurd: Fix exec usage of mach_setup_thread 2018-08-01 00:10:03 +02:00
iconv Fix s390 -Os iconv build. 2018-03-05 21:46:55 +00:00
iconvdata Fix out-of-bounds access in IBM-1390 converter (bug 23448) 2018-07-24 16:45:46 +02:00
include CVE-2016-10739: getaddrinfo: Fully parse IPv4 address strings [BZ #20018] 2019-02-04 21:36:37 +01:00
inet inet/tst-if_index-long: New test case for CVE-2018-19591 [BZ #23927] 2018-12-12 12:04:12 +01:00
intl intl: Do not return NULL on asprintf failure in gettext [BZ #24018] 2019-01-02 16:46:12 +01:00
io Avoid insecure usage of tmpnam in tests. 2018-07-18 21:04:12 +00:00
libio Increase timeout of libio/tst-readline 2018-11-19 14:21:24 +01:00
locale Fix out of bounds access in findidxwc (bug 23442) 2018-07-25 10:50:03 +02:00
localedata kl_GL: Fix spelling of Sunday, should be "sapaat" (bug 20209). 2018-10-09 00:50:20 +02:00
login Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
mach hurd: Fix exec usage of mach_setup_thread 2018-08-01 00:10:03 +02:00
malloc malloc: Always call memcpy in _int_realloc [BZ #24027] 2019-01-01 10:46:55 +01:00
manual malloc: tcache double free check 2018-11-28 15:45:42 -05:00
math Add XFAIL_ROUNDING_IBM128_LIBGCC to more fma() tests 2019-01-16 15:55:23 -02:00
mathvec Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
misc Fix misreported errno on preadv2/pwritev2 (BZ#23579) 2018-09-28 15:32:43 -03:00
nis nisplus: Correct pwent parsing issue and resulting build error [BZ #23266] 2018-06-27 21:12:16 +01:00
nptl nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161] 2019-02-08 12:55:21 +01:00
nptl_db nptl_db: Remove stale `match_pid' parameter from `iterate_thread_list' 2018-03-01 16:10:05 +00:00
nscd nscd: Do not use __inet_aton_exact@GLIBC_PRIVATE [BZ #20018] 2019-02-04 21:36:38 +01:00
nss CVE-2016-10739: getaddrinfo: Fully parse IPv4 address strings [BZ #20018] 2019-02-04 21:36:37 +01:00
po Synchronize translation project PO files. 2018-08-01 01:01:42 -04:00
posix regex: Add test tst-regcomp-truncated [BZ #23578] 2018-08-28 21:55:13 +02:00
pwd manual: Revise crypt.texi. 2018-06-29 16:53:37 +02:00
resolv CVE-2016-10739: getaddrinfo: Fully parse IPv4 address strings [BZ #20018] 2019-02-04 21:36:37 +01:00
resource resource/tst-getrlimit.c: Add copyright header 2018-01-05 20:34:10 +01:00
rt hurd: Add hurd thread library 2018-04-02 01:44:14 +02:00
scripts Use binutils 2.31 branch in build-many-glibcs.py. 2018-07-20 16:11:15 +00:00
setjmp x86: Use pad in pthread_unwind_buf to preserve shadow stack register 2018-05-02 06:17:41 -07:00
shadow manual: Revise crypt.texi. 2018-06-29 16:53:37 +02:00
signal Add tst-sigaction.c to test BZ #23069 2018-04-26 22:21:13 +02:00
socket Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
soft-fp Make powerpc-nofpu __sqrtsf2, __sqrtdf2 compat symbols (bug 18473). 2018-06-01 17:25:12 +00:00
stdio-common Avoid insecure usage of tmpnam in tests. 2018-07-18 21:04:12 +00:00
stdlib stdlib/tst-strtod-overflow: Switch to support_blob_repeat 2018-11-02 10:47:16 +01:00
streams Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
string Only build libm with -fno-math-errno (bug 24024) 2019-01-08 21:06:25 +01:00
sunrpc libc: Extend __libc_freeres framework (Bug 23329). 2018-06-29 22:39:06 -04:00
support support: Do not require overflow builtin in support/blob_repeat.c 2018-12-15 19:09:25 +01:00
sysdeps nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161] 2019-02-08 12:55:21 +01:00
sysvipc Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
termios Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
time Fix tzfile low-memory assertion failure 2018-11-09 10:17:13 -05:00
timezone Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
wcsmbs Add tests for sign of NaN returned by strtod (bug 23007). 2018-06-15 17:36:21 +00:00
wctype Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
.gitattributes
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COPYING
COPYING.LIB
ChangeLog nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161] 2019-02-08 12:55:21 +01:00
INSTALL Update tooling versions verified to work with glibc. 2018-07-31 16:37:07 -04:00
LICENSES stdio-common/tst-printf.c: Remove part under a non-free license [BZ #23363] 2018-07-03 18:29:16 +02:00
MAINTAINERS
Makeconfig Only build libm with -fno-math-errno (bug 24024) 2019-01-08 21:06:25 +01:00
Makefile testrun.sh: Implement --tool=strace, --tool=valgrind 2018-07-04 15:30:45 +02:00
Makefile.in
Makerules Run thread shutdown functions in an explicit order 2018-06-26 15:27:12 +02:00
NEWS nptl: Avoid fork handler lock for async-signal-safe fork [BZ #24161] 2019-02-08 12:55:21 +01:00
README Remove tilegx port. 2018-04-27 19:11:24 +00:00
Rules Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
abi-tags
aclocal.m4 LIBC_SLIBDIR_RTLDDIR: substitute arguments in single quotes 2018-01-25 17:20:28 +01:00
config.h.in Switch IDNA implementation to libidn2 [BZ #19728] [BZ #19729] [BZ #22247] 2018-05-23 15:27:24 +02:00
config.make.in New configure option --disable-crypt. 2018-06-29 16:53:47 +02:00
configure x86: Support IBT and SHSTK in Intel CET [BZ #21598] 2018-07-16 14:08:27 -07:00
configure.ac x86: Support IBT and SHSTK in Intel CET [BZ #21598] 2018-07-16 14:08:27 -07:00
extra-lib.mk
gen-locales.mk Improve gen-locales.mk and gen-locale.sh to make test files with @ options work 2018-02-27 17:01:57 +01:00
libc-abis libc-abis: Define ABSOLUTE ABI [BZ #19818][BZ #23307] 2018-07-05 18:06:43 +01:00
libof-iterator.mk
o-iterator.mk
shlib-versions
test-skeleton.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
version.h Update NEWS, version.h, and features.h for glibc 2.28. 2018-08-01 01:10:47 -04:00

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