user/sven/linux.git/arch/arc, branch v4.8.5

arc: don't leak bits of kernel stack into coredump

2016-10-28T07:45:26Z

commit 7798bf2140ebcc36eafec6a4194fffd8d585d471 upstream. On faulting sigreturn we do get SIGSEGV, all right, but anything we'd put into pt_regs could end up in the coredump. And since __copy_from_user() never zeroed on arc, we'd better bugger off on its failure without copying random uninitialized bits of kernel stack into pt_regs... Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

ARCv2: fix local_save_flags

2016-10-22T10:40:21Z

commit cd5d38b052384daa2893e9a1d94900d5a20ed4b5 upstream. Commit d9676fa152c83b ("ARCv2: Enable LOCKDEP"), changed local_save_flags() to not return raw STATUS32 but encoded in the form such that it could be fed directly to CLRI/SETI instructions. However the STATUS32.E[] was not captured correctly as it corresponds to bits [4:1] in the register and not [3:0] Fixes: d9676fa152c83b ("ARCv2: Enable LOCKDEP") Cc: Evgeny Voevodin Signed-off-by: Vineet Gupta Signed-off-by: Greg Kroah-Hartman

ARCv2: intc: Use kflag if STATUS32.IE must be reset

2016-10-22T10:40:21Z

commit bc0c7ece6191d89f435e4e4016f74167430c6c21 upstream. In the end of "arc_init_IRQ" STATUS32.IE flag is going to be affected by "flag" instruction but "flag" never touches IE flag on ARCv2. So "kflag" instruction must be used instead of "flag". Signed-off-by: Yuriy Kolerov Signed-off-by: Vineet Gupta Signed-off-by: Greg Kroah-Hartman

Merge branch 'uaccess-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-09-14T16:35:05Z

Pull uaccess fixes from Al Viro: "Fixes for broken uaccess primitives - mostly lack of proper zeroing in copy_from_user()/get_user()/__get_user(), but for several architectures there's more (broken clear_user() on frv and strncpy_from_user() on hexagon)" * 'uaccess-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits) avr32: fix copy_from_user() microblaze: fix __get_user() microblaze: fix copy_from_user() m32r: fix __get_user() blackfin: fix copy_from_user() sparc32: fix copy_from_user() sh: fix copy_from_user() sh64: failing __get_user() should zero score: fix copy_from_user() and friends score: fix __get_user/get_user s390: get_user() should zero on failure ppc32: fix copy_from_user() parisc: fix copy_from_user() openrisc: fix copy_from_user() nios2: fix __get_user() nios2: copy_from_user() should zero the tail of destination mn10300: copy_from_user() should zero on access_ok() failure... mn10300: failing __get_user() and get_user() should zero mips: copy_from_user() must zero the destination on access_ok() failure ARC: uaccess: get_user to zero out dest in cause of fault ...

ARC: uaccess: get_user to zero out dest in cause of fault

2016-09-13T21:49:41Z

Al reported potential issue with ARC get_user() as it wasn't clearing out destination pointer in case of fault due to bad address etc. Verified using following | { | u32 bogus1 = 0xdeadbeef; | u64 bogus2 = 0xdead; | int rc1, rc2; | | pr_info("Orig values %x %llx\n", bogus1, bogus2); | rc1 = get_user(bogus1, (u32 __user *)0x40000000); | rc2 = get_user(bogus2, (u64 __user *)0x50000000); | pr_info("access %d %d, new values %x %llx\n", | rc1, rc2, bogus1, bogus2); | } | [ARCLinux]# insmod /mnt/kernel-module/qtn.ko | Orig values deadbeef dead | access -14 -14, new values 0 0 Reported-by: Al Viro Cc: Linus Torvalds Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta Signed-off-by: Al Viro

ARC: export __udivdi3 for modules

2016-08-19T21:09:33Z

Some module using div_u64() was failing to link because the libgcc 64-bit divide assist routine was not being exported for modules Reported-by: avinashp@quantenna.com Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta

ARC: mm: fix build breakage with STRICT_MM_TYPECHECKS

2016-08-19T18:04:57Z

| CC mm/memory.o | In file included from ../mm/memory.c:53:0: | ../include/linux/pfn_t.h: In function ‘pfn_t_pte’: | ../include/linux/pfn_t.h:78:2: error: conversion to non-scalar type requested | return pfn_pte(pfn_t_to_pfn(pfn), pgprot); With STRICT_MM_TYPECHECKS pte_t is a struct and the offending code forces a cast which ends up shifting a struct and hence the gcc warning. Note that in recent past some of the arches (aarch64, s390) made STRICT_MM_TYPECHECKS default, but we don't for ARC as this leads to slightly worse generated code, given ARC ABI definition of returning structs (which pte_t would become) Quoting from ARC ABI... "Results of type struct are returned in a caller-supplied temporary variable whose address is passed in r0. For such functions, the arguments are shifted so that they are passed in r1 and up." So - struct to be returned would be allocated on stack requiring extra code at call sites - callee updates stack memory to facilitate the return (vs. simple MOV into return reg r0) Hence STRICT_MM_TYPECHECKS is not enabled by default for ARC Cc: #4.4+ Signed-off-by: Vineet Gupta

ARC: export kmap

2016-08-19T17:45:29Z

| MODPOST 7 modules | ERROR: "kmap" [fs/ext2/ext2.ko] undefined! | ../scripts/Makefile.modpost:91: recipe for target '__modpost' failed Cc: Signed-off-by: Vineet Gupta

ARC: Support syscall ABI v4

2016-08-19T17:44:34Z

The syscall ABI includes the gcc functional calling ABI since a syscall implies userland caller and kernel callee. The current gcc ABI (v3) for ARCv2 ISA required 64-bit data be passed in even-odd register pairs, (potentially punching reg holes when passing such values as args). This was partly driven by the fact that the double-word LDD/STD instructions in ARCv2 expect the register alignment and thus gcc forcing this avoids extra MOV at the cost of a few unused register (which we have plenty anyways). This however was rejected as part of upstreaming gcc port to HS. So the new ABI v4 doesn't enforce the even-odd reg restriction. Do note that for ARCompact ISA builds v3 and v4 are practically the same in terms of gcc code generation. In terms of change management, we infer the new ABI if gcc 6.x onwards is used for building the kernel. This also needs a stable backport to enable older kernels to work with new tools/user-space Cc: Signed-off-by: Vineet Gupta

ARC: use correct offset in pt_regs for saving/restoring user mode r25

2016-08-19T17:44:13Z

User mode callee regs are explicitly collected before signal delivery or breakpoint trap. r25 is special for kernel as it serves as task pointer, so user mode value is clobbered very early. It is saved in pt_regs where generally only scratch (aka caller saved) regs are saved. The code to access the corresponding pt_regs location had a subtle bug as it was using load/store with scaling of offset, whereas the offset was already byte wise correct. So fix this by replacing LD.AS with a standard LD Cc: Signed-off-by: Liav Rehana Reviewed-by: Alexey Brodkin [vgupta: rewrote title and commit log] Signed-off-by: Vineet Gupta