Linus Torvalds 1a8d05a726 VM_FAULT_RETRY fixes ... Some of the page fault handlers do not deal with the following case correctly: * handle_mm_fault() has returned VM_FAULT_RETRY * there is a pending fatal signal * fault had happened in kernel mode Correct action in such case is not "return unconditionally" - fatal signals are handled only upon return to userland and something like copy_to_user() would end up retrying the faulting instruction and triggering the same fault again and again. What we need to do in such case is to make the caller to treat that as failed uaccess attempt - handle exception if there is an exception handler for faulting instruction or oops if there isn't one. Over the years some architectures had been fixed and now are handling that case properly; some still do not. This series should fix the remaining ones. Status: m68k, riscv, hexagon, parisc: tested/acked by maintainers. alpha, sparc32, sparc64: tested locally - bug has been reproduced on the unpatched kernel and verified to be fixed by this series. ia64, microblaze, nios2, openrisc: build, but otherwise completely untested. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCZAP54AAKCRBZ7Krx/gZQ 6/IjAP92oS8kDuodAtT7WorV+GETWr2HFKfvDiPSmEGiSnXIigD9Hj9svXyeeAgl /TqGR50Yrvn3IUQ0A0bUDpBAG1qyVwY= =9+Bd -----END PGP SIGNATURE----- Merge tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VM_FAULT_RETRY fixes from Al Viro: "Some of the page fault handlers do not deal with the following case correctly: - handle_mm_fault() has returned VM_FAULT_RETRY - there is a pending fatal signal - fault had happened in kernel mode Correct action in such case is not "return unconditionally" - fatal signals are handled only upon return to userland and something like copy_to_user() would end up retrying the faulting instruction and triggering the same fault again and again. What we need to do in such case is to make the caller to treat that as failed uaccess attempt - handle exception if there is an exception handler for faulting instruction or oops if there isn't one. Over the years some architectures had been fixed and now are handling that case properly; some still do not. This series should fix the remaining ones. Status: - m68k, riscv, hexagon, parisc: tested/acked by maintainers. - alpha, sparc32, sparc64: tested locally - bug has been reproduced on the unpatched kernel and verified to be fixed by this series. - ia64, microblaze, nios2, openrisc: build, but otherwise completely untested" * tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: openrisc: fix livelock in uaccess nios2: fix livelock in uaccess microblaze: fix livelock in uaccess ia64: fix livelock in uaccess sparc: fix livelock in uaccess alpha: fix livelock in uaccess parisc: fix livelock in uaccess hexagon: fix livelock in uaccess riscv: fix livelock in uaccess m68k: fix livelock in uaccess		2023-03-05 11:07:58 -08:00
..
boot	SoC: DT changes for 6.3	2023-02-20 15:49:56 -08:00
configs	riscv: defconfig: Enable the Allwinner D1 platform and drivers	2023-01-27 23:10:08 +01:00
errata	RISC-V: take text_mutex during alternative patching	2023-02-21 17:21:33 -08:00
include	RISC-V Patches for the 6.3 Merge Window, Part 2	2023-03-03 09:32:51 -08:00
kernel	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
kvm	ARM:	2023-02-25 11:30:21 -08:00
lib	riscv, lib: Fix Zbb strncmp	2023-02-28 18:42:38 -08:00
mm	VM_FAULT_RETRY fixes	2023-03-05 11:07:58 -08:00
net	riscv, bpf: Add bpf trampoline support for RV64	2023-02-17 21:45:30 +01:00
purgatory	RISC-V: add infrastructure to allow different str* implementations	2023-01-31 11:43:23 -08:00
Kbuild	riscv: move errata/ and kvm/ builds to arch/riscv/Kbuild	2022-06-01 22:26:32 -07:00
Kconfig	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
Kconfig.debug	RISC-V: Remove EARLY_PRINTK support	2018-12-17 10:23:46 -08:00
Kconfig.erratas	drivers/perf: riscv_pmu_sbi: add support for PMU variant on T-Head C9xx cores	2022-10-27 14:35:20 -07:00
Kconfig.socs	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00
Makefile	RISC-V Patches for the 6.3 Merge Window, Part 1	2023-02-25 11:14:08 -08:00