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/compress.h | 91 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 tools/perf/util/compress.h (limited to 'tools/perf/util/compress.h') diff --git a/tools/perf/util/compress.h b/tools/perf/util/compress.h new file mode 100644 index 000000000..6cfecfca1 --- /dev/null +++ b/tools/perf/util/compress.h @@ -0,0 +1,91 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef PERF_COMPRESS_H +#define PERF_COMPRESS_H + +#include +#include +#include +#include +#include +#ifdef HAVE_ZSTD_SUPPORT +#include +#endif + +#ifdef HAVE_ZLIB_SUPPORT +int gzip_decompress_to_file(const char *input, int output_fd); +bool gzip_is_compressed(const char *input); +#endif + +#ifdef HAVE_LZMA_SUPPORT +int lzma_decompress_stream_to_file(FILE *input, int output_fd); +int lzma_decompress_to_file(const char *input, int output_fd); +bool lzma_is_compressed(const char *input); +#else +static inline +int lzma_decompress_stream_to_file(FILE *input __maybe_unused, + int output_fd __maybe_unused) +{ + return -1; +} +static inline +int lzma_decompress_to_file(const char *input __maybe_unused, + int output_fd __maybe_unused) +{ + return -1; +} +static inline int lzma_is_compressed(const char *input __maybe_unused) +{ + return false; +} +#endif + +struct zstd_data { +#ifdef HAVE_ZSTD_SUPPORT + ZSTD_CStream *cstream; + ZSTD_DStream *dstream; + int comp_level; +#endif +}; + +#ifdef HAVE_ZSTD_SUPPORT + +int zstd_init(struct zstd_data *data, int level); +int zstd_fini(struct zstd_data *data); + +ssize_t zstd_compress_stream_to_records(struct zstd_data *data, void *dst, size_t dst_size, + void *src, size_t src_size, size_t max_record_size, + size_t process_header(void *record, size_t increment)); + +size_t zstd_decompress_stream(struct zstd_data *data, void *src, size_t src_size, + void *dst, size_t dst_size); +#else /* !HAVE_ZSTD_SUPPORT */ + +static inline int zstd_init(struct zstd_data *data __maybe_unused, int level __maybe_unused) +{ + return 0; +} + +static inline int zstd_fini(struct zstd_data *data __maybe_unused) +{ + return 0; +} + +static inline +ssize_t zstd_compress_stream_to_records(struct zstd_data *data __maybe_unused, + void *dst __maybe_unused, size_t dst_size __maybe_unused, + void *src __maybe_unused, size_t src_size __maybe_unused, + size_t max_record_size __maybe_unused, + size_t process_header(void *record, size_t increment) __maybe_unused) +{ + return 0; +} + +static inline size_t zstd_decompress_stream(struct zstd_data *data __maybe_unused, void *src __maybe_unused, + size_t src_size __maybe_unused, void *dst __maybe_unused, + size_t dst_size __maybe_unused) +{ + return 0; +} +#endif + +#endif /* PERF_COMPRESS_H */ -- cgit v1.3.1