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Florian Weimer 2849e2f533 nptl: Avoid setxid deadlock with blocked signals in thread exit [BZ #28361]
As part of the fix for bug 12889, signals are blocked during
thread exit, so that application code cannot run on the thread that
is about to exit.  This would cause problems if the application
expected signals to be delivered after the signal handler revealed
the thread to still exist, despite pthread_kill can no longer be used
to send signals to it.  However, glibc internally uses the SIGSETXID
signal in a way that is incompatible with signal blocking, due to the
way the setxid handshake delays thread exit until the setxid operation
has completed.  With a blocked SIGSETXID, the handshake can never
complete, causing a deadlock.

As a band-aid, restore the previous handshake protocol by not blocking
SIGSETXID during thread exit.

The new test sysdeps/pthread/tst-pthread-setuid-loop.c is based on
a downstream test by Martin Osvald.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-09-23 09:56:07 +02:00
argp Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
assert
benchtests benchtests: Fix validate_benchout.py exceptions 2021-09-16 09:19:55 +05:30
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ChangeLog.old
conform Use $(pie-default) with conformtest 2021-09-17 19:24:14 +00:00
crypt Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
csu Extend struct r_debug to support multiple namespaces [BZ #15971] 2021-09-19 13:51:35 -07:00
ctype
debug Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
dirent Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
dlfcn Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
elf ld.so: Replace DL_RO_DYN_SECTION with dl_relocate_ld [BZ #28340] 2021-09-22 11:12:43 -07:00
gmon Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
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htl htl: Move thread table to ld.so 2021-09-16 01:04:05 +02:00
hurd Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
iconv iconvconfig: Fix behaviour with --prefix [BZ #28199] 2021-09-13 20:48:35 +05:30
iconvdata Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
include ld.so: Replace DL_RO_DYN_SECTION with dl_relocate_ld [BZ #28340] 2021-09-22 11:12:43 -07:00
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locale locale: Add missing second argument to _Static_assert in C-collate-seq.c 2021-09-06 19:43:37 +02:00
localedata Add generic C.UTF-8 locale (Bug 17318) 2021-09-06 11:30:28 -04:00
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malloc Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
manual Add narrowing fma functions 2021-09-22 21:25:31 +00:00
math Add narrowing fma functions 2021-09-22 21:25:31 +00:00
mathvec
misc regex: copy back from Gnulib 2021-09-21 08:00:44 -07:00
nis Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
nptl nptl: Avoid setxid deadlock with blocked signals in thread exit [BZ #28361] 2021-09-23 09:56:07 +02:00
nptl_db Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
nscd Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
nss Fix failing nss/tst-nss-files-hosts-long with local resolver 2021-09-07 21:41:38 +02:00
po
posix regex: copy back from Gnulib 2021-09-21 08:00:44 -07:00
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scripts Fix build-many-glibcs.py --strip for installed library renaming 2021-09-16 14:08:05 +00:00
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support time: Fix compile error in itimer test affecting hurd 2021-09-16 05:21:08 +09:00
sysdeps nptl: Avoid setxid deadlock with blocked signals in thread exit [BZ #28361] 2021-09-23 09:56:07 +02:00
sysvipc Remove "Contributed by" lines 2021-09-03 22:06:44 +05:30
termios
time time: Fix compile error in itimer test affecting hurd 2021-09-16 05:21:08 +09:00
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configure configure: Fix check for INSERT in linker script 2021-09-13 12:39:20 -07:00
configure.ac configure: Fix check for INSERT in linker script 2021-09-13 12:39:20 -07:00
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Makeconfig Run conform/ tests using newly built libc 2021-09-17 13:12:10 +00:00
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This directory contains the sources of the GNU C Library.
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