glibc/sysdeps/unix
Sudakshina Das 605338745b aarch64: enable BTI at runtime
Binaries can opt-in to using BTI via an ELF object file marking.
The dynamic linker has to then mprotect the executable segments
with PROT_BTI. In case of static linked executables or in case
of the dynamic linker itself, PROT_BTI protection is done by the
operating system.

On AArch64 glibc uses PT_GNU_PROPERTY instead of PT_NOTE to check
the properties of a binary because PT_NOTE can be unreliable with
old linkers (old linkers just append the notes of input objects
together and add them to the output without checking them for
consistency which means multiple incompatible GNU property notes
can be present in PT_NOTE).

BTI property is handled in the loader even if glibc is not built
with BTI support, so in theory user code can be BTI protected
independently of glibc. In practice though user binaries are not
marked with the BTI property if glibc has no support because the
static linked libc objects (crt files, libc_nonshared.a) are
unmarked.

This patch relies on Linux userspace API that is not yet in a
linux release but in v5.8-rc1 so scheduled to be in Linux 5.8.

Co-authored-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2020-07-08 15:02:37 +01:00
..
alpha alpha: Refactor syscall and Use Linux kABI for syscall return 2020-02-14 21:09:12 -03:00
arm linux: Consolidate INLINE_SYSCALL 2020-02-14 21:09:12 -03:00
bsd signal: Add signum-{generic,arch}.h 2020-07-07 14:10:58 -03:00
i386 i386: Remove unused file sysdeps/unix/i386/sysdep.S 2020-05-28 13:44:29 +02:00
inet Remove obsolete, never-implemented XSI STREAMS declarations 2019-03-14 15:44:15 +01:00
mips linux: Consolidate INLINE_SYSCALL 2020-02-14 21:09:12 -03:00
powerpc Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
sh linux: Consolidate INLINE_SYSCALL 2020-02-14 21:09:12 -03:00
sysv/linux aarch64: enable BTI at runtime 2020-07-08 15:02:37 +01:00
x86_64 linux: Consolidate INLINE_SYSCALL 2020-02-14 21:09:12 -03:00
confstr.h
get_child_max.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
getlogin_r.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
getlogin.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
getpagesize.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
grantpt.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
ifreq.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Implies
make-syscalls.sh Add SYSCALL_ULONG_ARG_[12] to pass long to syscall [BZ #25810] 2020-04-29 05:35:34 -07:00
Makefile Add arch-syscall.h dependency for generating sysd-syscalls file 2020-05-14 18:40:58 +02:00
pt-fcntl.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
s-proto-cancel.S
s-proto.S
setxid.h
sockatmark.c Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
syscall-template.S Add SYSCALL_ULONG_ARG_[12] to pass long to syscall [BZ #25810] 2020-04-29 05:35:34 -07:00
syscall.S Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
syscalls.list Mark unsigned long arguments with U in more syscalls [BZ #25810] 2020-04-29 08:10:01 -07:00
sysdep.h linux: Remove INTERNAL_SYSCALL_DECL 2020-02-14 21:12:45 -03:00