From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- tools/perf/util/capstone.h | 57 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 tools/perf/util/capstone.h (limited to 'tools/perf/util/capstone.h') diff --git a/tools/perf/util/capstone.h b/tools/perf/util/capstone.h new file mode 100644 index 000000000..7c0baaa01 --- /dev/null +++ b/tools/perf/util/capstone.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PERF_CAPSTONE_H +#define __PERF_CAPSTONE_H + +#include +#include +#include +#include +#include +#include + +struct annotate_args; +struct machine; +struct symbol; +struct thread; + +#ifdef HAVE_LIBCAPSTONE_SUPPORT +ssize_t capstone__fprintf_insn_asm(struct machine *machine, struct thread *thread, u8 cpumode, + bool is64bit, const uint8_t *code, size_t code_size, + uint64_t ip, int *lenp, int print_opts, FILE *fp); +int symbol__disassemble_capstone(const char *filename, struct symbol *sym, + struct annotate_args *args); +int symbol__disassemble_capstone_powerpc(const char *filename, struct symbol *sym, + struct annotate_args *args); + +#else /* !HAVE_LIBCAPSTONE_SUPPORT */ +static inline ssize_t capstone__fprintf_insn_asm(struct machine *machine __maybe_unused, + struct thread *thread __maybe_unused, + u8 cpumode __maybe_unused, + bool is64bit __maybe_unused, + const uint8_t *code __maybe_unused, + size_t code_size __maybe_unused, + uint64_t ip __maybe_unused, + int *lenp __maybe_unused, + int print_opts __maybe_unused, + FILE *fp __maybe_unused) +{ + return -1; +} + +static inline int symbol__disassemble_capstone(const char *filename __maybe_unused, + struct symbol *sym __maybe_unused, + struct annotate_args *args __maybe_unused) +{ + return -1; +} + +static inline int symbol__disassemble_capstone_powerpc(const char *filename __maybe_unused, + struct symbol *sym __maybe_unused, + struct annotate_args *args __maybe_unused) +{ + return -1; +} + +#endif /* HAVE_LIBCAPSTONE_SUPPORT */ + +#endif /* __PERF_CAPSTONE_H */ -- cgit v1.3.1