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Hector Martin 3921c5b40f elf: Fix TLS modid reuse generation assignment (BZ 29039)
_dl_assign_tls_modid() assigns a slotinfo entry for a new module, but
does *not* do anything to the generation counter. The first time this
happens, the generation is zero and map_generation() returns the current
generation to be used during relocation processing. However, if
a slotinfo entry is later reused, it will already have a generation
assigned. If this generation has fallen behind the current global max
generation, then this causes an obsolete generation to be assigned
during relocation processing, as map_generation() returns this
generation if nonzero. _dl_add_to_slotinfo() eventually resets the
generation, but by then it is too late. This causes DTV updates to be
skipped, leading to NULL or broken TLS slot pointers and segfaults.

Fix this by resetting the generation to zero in _dl_assign_tls_modid(),
so it behaves the same as the first time a slot is assigned.
_dl_add_to_slotinfo() will still assign the correct static generation
later during module load, but relocation processing will no longer use
an obsolete generation.

Note that slotinfo entry (aka modid) reuse typically happens after a
dlclose and only TLS access via dynamic tlsdesc is affected. Because
tlsdesc is optimized to use the optional part of static TLS, dynamic
tlsdesc can be avoided by increasing the glibc.rtld.optional_static_tls
tunable to a large enough value, or by LD_PRELOAD-ing the affected
modules.

Fixes bug 29039.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2023-11-28 17:28:02 +00:00
argp argp-parse: Get rid of alloca 2023-08-28 16:49:27 +00:00
assert assert: Decorate error message buffer 2023-11-07 10:27:44 -03:00
benchtests
bits linux: Add posix_spawnattr_{get, set}cgroup_np (BZ 26371) 2023-09-05 13:08:48 -03:00
catgets gencat: Get rid of alloca. 2023-08-28 16:42:53 +00:00
ChangeLog.old Create ChangeLog.old/ChangeLog.27 2023-07-30 21:45:27 +02:00
conform crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
csu
ctype
debug debug: Add regression tests for BZ 30932 2023-10-04 08:07:43 -03:00
dirent
dlfcn
elf elf: Fix TLS modid reuse generation assignment (BZ 29039) 2023-11-28 17:28:02 +00:00
gmon
gnulib
hesiod
htl __call_tls_dtors: Use call_function_static_weak 2023-09-04 20:03:37 +02:00
hurd hurd: fix restarting reauth_dtable on signal 2023-11-21 00:55:54 +01:00
iconv Fix off-by-one OOB write in iconv/tst-iconv-mt 2023-10-04 08:33:20 +01:00
iconvdata add GB18030-2022 charmap and test the entire GB18030 charmap [BZ #30243] 2023-08-29 19:02:30 +02:00
include malloc: Use __get_nprocs on arena_get2 (BZ 30945) 2023-11-22 09:39:29 -03:00
inet Move getnameinfo from 'inet' to 'nss' 2023-10-24 12:31:00 +02:00
intl intl: Add test case for bug 16621 2023-11-20 16:03:11 +01:00
io Remove __access_noerrno 2023-11-23 19:01:32 +00:00
libio libio: Add nonnull attribute for most FILE * arguments in stdio.h 2023-09-26 20:11:38 -04:00
locale crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
localedata localedata: Convert oc_FR locale to UTF-8 2023-11-16 23:58:17 +01:00
login
mach Remove untyped mach RPC code. 2023-11-19 10:21:28 +01:00
malloc malloc: Use __get_nprocs on arena_get2 (BZ 30945) 2023-11-22 09:39:29 -03:00
manual elf: Ignore GLIBC_TUNABLES for setuid/setgid binaries 2023-11-21 16:15:42 -03:00
math aarch64: Add vector implementations of expm1 routines 2023-11-20 17:53:14 +00:00
mathvec
misc malloc: Use __get_nprocs on arena_get2 (BZ 30945) 2023-11-22 09:39:29 -03:00
nis
nptl nptl: Link tst-execstack-threads-mod.so with -z execstack 2023-11-20 09:22:25 +01:00
nptl_db
nscd Move 'netgroup' routines from 'inet' into 'nss' 2023-10-24 12:30:59 +02:00
nss Move getnameinfo from 'inet' to 'nss' 2023-10-24 12:31:00 +02:00
po
posix posix: Revert the removal of the crypt prototype from <unistd.h> 2023-11-22 08:38:33 +01:00
resolv resolv: free only initialized items from gai pool 2023-11-20 15:03:29 +01:00
resource
rt
scripts elf: Ignore GLIBC_TUNABLES for setuid/setgid binaries 2023-11-21 16:15:42 -03:00
setjmp chk: Add and fix hidden builtin definitions for *_chk 2023-08-03 22:46:48 +02:00
signal
socket
soft-fp
stdio-common elf: Fix _dl_debug_vdprintf to work before self-relocation 2023-11-21 16:15:42 -03:00
stdlib stdlib: The qsort implementation needs to use heapsort in more cases 2023-11-21 16:46:18 +01:00
string string: Add internal memswap implementation 2023-10-31 14:17:33 -03:00
sunrpc Move 'rpc' routines from 'inet' into 'nss' 2023-10-24 12:31:00 +02:00
support support: Add support_set_vma_name 2023-11-07 10:27:20 -03:00
sysdeps Add TCP_MD5SIG_FLAG_IFINDEX from Linux 5.6 to netinet/tcp.h. 2023-11-28 13:44:47 +01:00
sysvipc
termios
time
timezone
wcsmbs Add strlcat/wcslcat testcase. 2023-10-17 18:19:01 -04:00
wctype
.clang-format
.gitattributes
.gitignore
abi-tags
aclocal.m4
config.h.in LoongArch: Add minuimum binutils required version 2023-08-14 09:47:09 +08:00
config.make.in crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
configure crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
configure.ac crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
CONTRIBUTED-BY crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
COPYING
COPYING.LIB
extra-lib.mk
gen-locales.mk
INSTALL crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
libc-abis
libof-iterator.mk
LICENSES
MAINTAINERS
Makeconfig crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
Makefile Format test results closer to what DejaGnu does 2023-11-03 12:58:17 +00:00
Makefile.help
Makefile.in
Makerules
NEWS posix: Revert the removal of the crypt prototype from <unistd.h> 2023-11-22 08:38:33 +01:00
o-iterator.mk
README
Rules
SECURITY.md
SHARED-FILES crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
shlib-versions crypt: Remove libcrypt support 2023-10-30 13:03:59 -03:00
test-skeleton.c
version.h Open master branch for glibc 2.39 development 2023-07-31 20:07:55 +02:00

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