Tycho Andersen af33d2433b riscv: fix seccomp reject syscall code path ... If secure_computing() rejected a system call, we were previously setting the system call number to -1, to indicate to later code that the syscall failed. However, if something (e.g. a user notification) was sleeping, and received a signal, we may set a0 to -ERESTARTSYS and re-try the system call again. In this case, seccomp "denies" the syscall (because of the signal), and we would set a7 to -1, thus losing the value of the system call we want to restart. Instead, let's return -1 from do_syscall_trace_enter() to indicate that the syscall was rejected, so we don't clobber the value in case of -ERESTARTSYS or whatever. This commit fixes the user_notification_signal seccomp selftest on riscv to no longer hang. That test expects the system call to be re-issued after the signal, and it wasn't due to the above bug. Now that it is, everything works normally. Note that in the ptrace (tracer) case, the tracer can set the register values to whatever they want, so we still need to keep the code that handles out-of-bounds syscalls. However, we can drop the comment. We can also drop syscall_set_nr(), since it is no longer used anywhere, and the code that re-loads the value in a7 because of it. Reported in: https://lore.kernel.org/bpf/CAEn-LTp=ss0Dfv6J00=rCAy+N78U2AmhqJNjfqjr2FDpPYjxEQ@mail.gmail.com/ Reported-by: David Abdurachmanov <david.abdurachmanov@gmail.com> Signed-off-by: Tycho Andersen <tycho@tycho.ws> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>		2020-03-05 13:58:15 -08:00
..
boot	riscv: dts: Add GPIO reboot method to HiFive Unleashed DTS file	2020-03-05 12:27:10 -08:00
configs	RISC-V: Select Goldfish RTC driver for QEMU virt machine	2020-03-05 10:48:46 -08:00
include	riscv: fix seccomp reject syscall code path	2020-03-05 13:58:15 -08:00
kernel	riscv: fix seccomp reject syscall code path	2020-03-05 13:58:15 -08:00
lib	riscv: Add KASAN support	2020-01-22 13:09:58 -08:00
mm	riscv: Fix range looking for kernel image memblock	2020-03-04 15:11:03 -08:00
net	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2019-12-27 14:20:10 -08:00
Kbuild	riscv: add arch/riscv/Kbuild	2019-08-30 17:34:00 -07:00
Kconfig	riscv: Force flat memory model with no-mmu	2020-03-04 10:38:17 -08:00
Kconfig.debug
Kconfig.socs	RISC-V: Select Goldfish RTC driver for QEMU virt machine	2020-03-05 10:48:46 -08:00
Makefile	riscv: Change code model of module to medany to improve data accessing	2020-03-03 10:27:46 -08:00