linux_dsm_epyc7002/arch
Will Deacon 784e0300fe rseq: Avoid infinite recursion when delivering SIGSEGV
When delivering a signal to a task that is using rseq, we call into
__rseq_handle_notify_resume() so that the registers pushed in the
sigframe are updated to reflect the state of the restartable sequence
(for example, ensuring that the signal returns to the abort handler if
necessary).

However, if the rseq management fails due to an unrecoverable fault when
accessing userspace or certain combinations of RSEQ_CS_* flags, then we
will attempt to deliver a SIGSEGV. This has the potential for infinite
recursion if the rseq code continuously fails on signal delivery.

Avoid this problem by using force_sigsegv() instead of force_sig(), which
is explicitly designed to reset the SEGV handler to SIG_DFL in the case
of a recursive fault. In doing so, remove rseq_signal_deliver() from the
internal rseq API and have an optional struct ksignal * parameter to
rseq_handle_notify_resume() instead.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: peterz@infradead.org
Cc: paulmck@linux.vnet.ibm.com
Cc: boqun.feng@gmail.com
Link: https://lkml.kernel.org/r/1529664307-983-1-git-send-email-will.deacon@arm.com
2018-06-22 19:04:22 +02:00
..
alpha Kbuild updates for v4.18 2018-06-06 11:00:15 -07:00
arc mm: introduce ARCH_HAS_PTE_SPECIAL 2018-06-07 17:34:35 -07:00
arm rseq: Avoid infinite recursion when delivering SIGSEGV 2018-06-22 19:04:22 +02:00
arm64 docs: Fix some broken references 2018-06-15 18:10:01 -03:00
c6x Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
h8300 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
hexagon hexagon: drop the unused variable zero_page_mask 2018-06-15 07:55:25 +09:00
ia64 - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2018-06-05 10:51:30 -07:00
microblaze docs: Fix some broken references 2018-06-15 18:10:01 -03:00
mips Merge branch 'akpm' (patches from Andrew) 2018-06-15 08:51:42 +09:00
nds32 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
nios2 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
openrisc Kbuild updates for v4.18 2018-06-06 11:00:15 -07:00
parisc arch/*: Kconfig: fix documentation for NMI watchdog 2018-06-15 12:48:59 -03:00
powerpc rseq: Avoid infinite recursion when delivering SIGSEGV 2018-06-22 19:04:22 +02:00
riscv RISC-V Updates for the 4.18 Merge Window 2018-06-16 06:42:43 +09:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2018-06-19 07:44:51 +09:00
sh arch/*: Kconfig: fix documentation for NMI watchdog 2018-06-15 12:48:59 -03:00
sparc arch/*: Kconfig: fix documentation for NMI watchdog 2018-06-15 12:48:59 -03:00
um Solve a series of broken links for files under Documentation: 2018-06-17 05:25:18 +09:00
unicore32 docs: Fix some broken references 2018-06-15 18:10:01 -03:00
x86 rseq: Avoid infinite recursion when delivering SIGSEGV 2018-06-22 19:04:22 +02:00
xtensa docs: Fix some broken references 2018-06-15 18:10:01 -03:00
.gitignore
Kconfig docs: Fix some broken references 2018-06-15 18:10:01 -03:00