kernel/linux.git/arch/powerpc/lib, branch v5.15.209

powerpc/code-patching: Fix KASAN hit by not flagging text patching area as VM_ALLOC

2025-03-13T11:50:52+00:00

[ Upstream commit d262a192d38e527faa5984629aabda2e0d1c4f54 ] Erhard reported the following KASAN hit while booting his PowerMac G4 with a KASAN-enabled kernel 6.13-rc6: BUG: KASAN: vmalloc-out-of-bounds in copy_to_kernel_nofault+0xd8/0x1c8 Write of size 8 at addr f1000000 by task chronyd/1293 CPU: 0 UID: 123 PID: 1293 Comm: chronyd Tainted: G W 6.13.0-rc6-PMacG4 #2 Tainted: [W]=WARN Hardware name: PowerMac3,6 7455 0x80010303 PowerMac Call Trace: [c2437590] [c1631a84] dump_stack_lvl+0x70/0x8c (unreliable) [c24375b0] [c0504998] print_report+0xdc/0x504 [c2437610] [c050475c] kasan_report+0xf8/0x108 [c2437690] [c0505a3c] kasan_check_range+0x24/0x18c [c24376a0] [c03fb5e4] copy_to_kernel_nofault+0xd8/0x1c8 [c24376c0] [c004c014] patch_instructions+0x15c/0x16c [c2437710] [c00731a8] bpf_arch_text_copy+0x60/0x7c [c2437730] [c0281168] bpf_jit_binary_pack_finalize+0x50/0xac [c2437750] [c0073cf4] bpf_int_jit_compile+0xb30/0xdec [c2437880] [c0280394] bpf_prog_select_runtime+0x15c/0x478 [c24378d0] [c1263428] bpf_prepare_filter+0xbf8/0xc14 [c2437990] [c12677ec] bpf_prog_create_from_user+0x258/0x2b4 [c24379d0] [c027111c] do_seccomp+0x3dc/0x1890 [c2437ac0] [c001d8e0] system_call_exception+0x2dc/0x420 [c2437f30] [c00281ac] ret_from_syscall+0x0/0x2c --- interrupt: c00 at 0x5a1274 NIP: 005a1274 LR: 006a3b3c CTR: 005296c8 REGS: c2437f40 TRAP: 0c00 Tainted: G W (6.13.0-rc6-PMacG4) MSR: 0200f932 CR: 24004422 XER: 00000000 GPR00: 00000166 af8f3fa0 a7ee3540 00000001 00000000 013b6500 005a5858 0200f932 GPR08: 00000000 00001fe9 013d5fc8 005296c8 2822244c 00b2fcd8 00000000 af8f4b57 GPR16: 00000000 00000001 00000000 00000000 00000000 00000001 00000000 00000002 GPR24: 00afdbb0 00000000 00000000 00000000 006e0004 013ce060 006e7c1c 00000001 NIP [005a1274] 0x5a1274 LR [006a3b3c] 0x6a3b3c --- interrupt: c00 The buggy address belongs to the virtual mapping at [f1000000, f1002000) created by: text_area_cpu_up+0x20/0x190 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:00000000 index:0x0 pfn:0x76e30 flags: 0x80000000(zone=2) raw: 80000000 00000000 00000122 00000000 00000000 00000000 ffffffff 00000001 raw: 00000000 page dumped because: kasan: bad access detected Memory state around the buggy address: f0ffff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f0ffff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >f1000000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ f1000080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f1000100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ================================================================== f8 corresponds to KASAN_VMALLOC_INVALID which means the area is not initialised hence not supposed to be used yet. Powerpc text patching infrastructure allocates a virtual memory area using get_vm_area() and flags it as VM_ALLOC. But that flag is meant to be used for vmalloc() and vmalloc() allocated memory is not supposed to be used before a call to __vmalloc_node_range() which is never called for that area. That went undetected until commit e4137f08816b ("mm, kasan, kmsan: instrument copy_from/to_kernel_nofault") The area allocated by text_area_cpu_up() is not vmalloc memory, it is mapped directly on demand when needed by map_kernel_page(). There is no VM flag corresponding to such usage, so just pass no flag. That way the area will be unpoisonned and usable immediately. Reported-by: Erhard Furtner Closes: https://lore.kernel.org/all/20250112135832.57c92322@yea/ Fixes: 37bc3e5fd764 ("powerpc/lib/code-patching: Use alternate map for patch_instruction()") Signed-off-by: Christophe Leroy Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/06621423da339b374f48c0886e3a5db18e896be8.1739342693.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin

powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static

2024-12-14T18:51:03+00:00

[ Upstream commit a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b ] These functions are not used outside of sstep.c Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de Signed-off-by: Sasha Levin

powerpc: xor_vmx: Add '-mhard-float' to CFLAGS

2024-04-10T14:19:30+00:00

commit 35f20786c481d5ced9283ff42de5c69b65e5ed13 upstream. arch/powerpc/lib/xor_vmx.o is built with '-msoft-float' (from the main powerpc Makefile) and '-maltivec' (from its CFLAGS), which causes an error when building with clang after a recent change in main: error: option '-msoft-float' cannot be specified with '-maltivec' make[6]: *** [scripts/Makefile.build:243: arch/powerpc/lib/xor_vmx.o] Error 1 Explicitly add '-mhard-float' before '-maltivec' in xor_vmx.o's CFLAGS to override the previous inclusion of '-msoft-float' (as the last option wins), which matches how other areas of the kernel use '-maltivec', such as AMDGPU. Cc: stable@vger.kernel.org Closes: https://github.com/ClangBuiltLinux/linux/issues/1986 Link: https://github.com/llvm/llvm-project/commit/4792f912b232141ecba4cbae538873be3c28556c Signed-off-by: Nathan Chancellor Signed-off-by: Michael Ellerman Link: https://msgid.link/20240127-ppc-xor_vmx-drop-msoft-float-v1-1-f24140e81376@kernel.org [nathan: Fixed conflicts due to lack of 04e85bbf71c9 in older trees] Signed-off-by: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

powerpc/lib: Validate size for vector operations

2024-02-23T07:54:37+00:00

[ Upstream commit 8f9abaa6d7de0a70fc68acaedce290c1f96e2e59 ] Some of the fp/vmx code in sstep.c assume a certain maximum size for the instructions being emulated. The size of those operations however is determined separately in analyse_instr(). Add a check to validate the assumption on the maximum size of the operations, so as to prevent any unintended kernel stack corruption. Signed-off-by: Naveen N Rao Reviewed-by: Gustavo A. R. Silva Build-tested-by: Gustavo A. R. Silva Signed-off-by: Michael Ellerman Link: https://msgid.link/20231123071705.397625-1-naveen@kernel.org Signed-off-by: Sasha Levin

powerpc: add crtsavres.o to always-y instead of extra-y

2024-01-25T22:52:32+00:00

[ Upstream commit 1b1e38002648819c04773647d5242990e2824264 ] crtsavres.o is linked to modules. However, as explained in commit d0e628cd817f ("kbuild: doc: clarify the difference between extra-y and always-y"), 'make modules' does not build extra-y. For example, the following command fails: $ make ARCH=powerpc LLVM=1 KBUILD_MODPOST_WARN=1 mrproper ps3_defconfig modules [snip] LD [M] arch/powerpc/platforms/cell/spufs/spufs.ko ld.lld: error: cannot open arch/powerpc/lib/crtsavres.o: No such file or directory make[3]: *** [scripts/Makefile.modfinal:56: arch/powerpc/platforms/cell/spufs/spufs.ko] Error 1 make[2]: *** [Makefile:1844: modules] Error 2 make[1]: *** [/home/masahiro/workspace/linux-kbuild/Makefile:350: __build_one_by_one] Error 2 make: *** [Makefile:234: __sub-make] Error 2 Signed-off-by: Masahiro Yamada Fixes: baa25b571a16 ("powerpc/64: Do not link crtsavres.o in vmlinux") Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://msgid.link/20231120232332.4100288-1-masahiroy@kernel.org Signed-off-by: Sasha Levin

powerpc: remove checks for binutils older than 2.25

2024-01-25T22:52:32+00:00

[ Upstream commit 54a11654de163994e32b24e3aa90ef81f4a3184d ] Commit e4412739472b ("Documentation: raise minimum supported version of binutils to 2.25") allows us to remove the checks for old binutils. There is no more user for ld-ifversion. Remove it as well. Signed-off-by: Masahiro Yamada Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://msgid.link/20230119082250.151485-1-masahiroy@kernel.org Stable-dep-of: 1b1e38002648 ("powerpc: add crtsavres.o to always-y instead of extra-y") Signed-off-by: Sasha Levin

powerpc: flexible GPR range save/restore macros

2022-07-12T14:35:02+00:00

[ Upstream commit aebd1fb45c622e9a2b06fb70665d084d3a8d6c78 ] Introduce macros that operate on a (start, end) range of GPRs, which reduces lines of code and need to do mental arithmetic while reading the code. Signed-off-by: Nicholas Piggin Reviewed-by: Segher Boessenkool Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211022061322.2671178-1-npiggin@gmail.com Signed-off-by: Sasha Levin

powerpc/lib/sstep: Fix build errors with newer binutils

2022-04-08T12:24:04+00:00

commit 8219d31effa7be5dbc7ff915d7970672e028c701 upstream. Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian 2.37.90.20220207) the following build error shows up: {standard input}: Assembler messages: {standard input}:10576: Error: unrecognized opcode: `stbcx.' {standard input}:10680: Error: unrecognized opcode: `lharx' {standard input}:10694: Error: unrecognized opcode: `lbarx' Rework to add assembler directives [1] around the instruction. The problem with this might be that we can trick a power6 into single-stepping through an stbcx. for instance, and it will execute that in kernel mode. [1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Cc: stable@vger.kernel.org # v4.14+ Co-developed-by: Arnd Bergmann Signed-off-by: Arnd Bergmann Signed-off-by: Anders Roxell Reviewed-by: Segher Boessenkool Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220224162215.3406642-3-anders.roxell@linaro.org Signed-off-by: Greg Kroah-Hartman

powerpc/lib/sstep: Fix 'sthcx' instruction

2022-04-08T12:24:04+00:00

commit a633cb1edddaa643fadc70abc88f89a408fa834a upstream. Looks like there been a copy paste mistake when added the instruction 'stbcx' twice and one was probably meant to be 'sthcx'. Changing to 'sthcx' from 'stbcx'. Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Cc: stable@vger.kernel.org # v4.14+ Reported-by: Arnd Bergmann Signed-off-by: Anders Roxell Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220224162215.3406642-1-anders.roxell@linaro.org Signed-off-by: Greg Kroah-Hartman

uaccess: fix type mismatch warnings from access_ok()

2022-04-08T12:24:01+00:00

[ Upstream commit 23fc539e81295b14b50c6ccc5baeb4f3d59d822d ] On some architectures, access_ok() does not do any argument type checking, so replacing the definition with a generic one causes a few warnings for harmless issues that were never caught before. Fix the ones that I found either through my own test builds or that were reported by the 0-day bot. Reported-by: kernel test robot Reviewed-by: Christoph Hellwig Acked-by: Dinh Nguyen Signed-off-by: Arnd Bergmann Signed-off-by: Sasha Levin