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/trace.h | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 tools/perf/util/trace.h (limited to 'tools/perf/util/trace.h') diff --git a/tools/perf/util/trace.h b/tools/perf/util/trace.h new file mode 100644 index 000000000..fbbcfe6f4 --- /dev/null +++ b/tools/perf/util/trace.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef UTIL_TRACE_H +#define UTIL_TRACE_H + +#include /* for FILE */ + +enum trace_summary_mode { + SUMMARY__NONE = 0, + SUMMARY__BY_TOTAL, + SUMMARY__BY_THREAD, + SUMMARY__BY_CGROUP, +}; + +#ifdef HAVE_BPF_SKEL + +int trace_prepare_bpf_summary(enum trace_summary_mode mode); +void trace_start_bpf_summary(void); +void trace_end_bpf_summary(void); +int trace_print_bpf_summary(FILE *fp, int max_summary); +void trace_cleanup_bpf_summary(void); + +#else /* !HAVE_BPF_SKEL */ + +static inline int trace_prepare_bpf_summary(enum trace_summary_mode mode __maybe_unused) +{ + return -1; +} +static inline void trace_start_bpf_summary(void) {} +static inline void trace_end_bpf_summary(void) {} +static inline int trace_print_bpf_summary(FILE *fp __maybe_unused, int max_summary __maybe_unused) +{ + return 0; +} +static inline void trace_cleanup_bpf_summary(void) {} + +#endif /* HAVE_BPF_SKEL */ + +#endif /* UTIL_TRACE_H */ -- cgit v1.3.1