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/string2.h | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 tools/perf/util/string2.h (limited to 'tools/perf/util/string2.h') diff --git a/tools/perf/util/string2.h b/tools/perf/util/string2.h new file mode 100644 index 000000000..4c8bff47c --- /dev/null +++ b/tools/perf/util/string2.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef PERF_STRING_H +#define PERF_STRING_H + +#include +#include +#include // pid_t +#include +#include + +extern const char *graph_dotted_line; +extern const char *dots; + +s64 perf_atoll(const char *str); +bool strglobmatch(const char *str, const char *pat); +bool strglobmatch_nocase(const char *str, const char *pat); +bool strlazymatch(const char *str, const char *pat); +static inline bool strisglob(const char *str) +{ + return strpbrk(str, "*?[") != NULL; +} +int strtailcmp(const char *s1, const char *s2); + +char *asprintf_expr_inout_ints(const char *var, bool in, size_t nints, int *ints); + +static inline char *asprintf_expr_in_ints(const char *var, size_t nints, int *ints) +{ + return asprintf_expr_inout_ints(var, true, nints, ints); +} + +static inline char *asprintf_expr_not_in_ints(const char *var, size_t nints, int *ints) +{ + return asprintf_expr_inout_ints(var, false, nints, ints); +} + +char *asprintf__tp_filter_pids(size_t npids, pid_t *pids); + +char *strpbrk_esc(char *str, const char *stopset); +char *strdup_esc(const char *str); +char *strpbrk_esq(char *str, const char *stopset); +char *strdup_esq(const char *str); + +unsigned int hex(char c); +char *strreplace_chars(char needle, const char *haystack, const char *replace); + +#endif /* PERF_STRING_H */ -- cgit v1.3.1