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/blake2s.h | 73 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 tools/perf/util/blake2s.h (limited to 'tools/perf/util/blake2s.h') diff --git a/tools/perf/util/blake2s.h b/tools/perf/util/blake2s.h new file mode 100644 index 000000000..a1fe81a4b --- /dev/null +++ b/tools/perf/util/blake2s.h @@ -0,0 +1,73 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ +/* + * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. + */ + +#ifndef _CRYPTO_BLAKE2S_H +#define _CRYPTO_BLAKE2S_H + +#include +#include + +#define BLAKE2S_BLOCK_SIZE 64 + +struct blake2s_ctx { + u32 h[8]; + u32 t[2]; + u32 f[2]; + u8 buf[BLAKE2S_BLOCK_SIZE]; + unsigned int buflen; + unsigned int outlen; +}; + +enum blake2s_iv { + BLAKE2S_IV0 = 0x6A09E667UL, + BLAKE2S_IV1 = 0xBB67AE85UL, + BLAKE2S_IV2 = 0x3C6EF372UL, + BLAKE2S_IV3 = 0xA54FF53AUL, + BLAKE2S_IV4 = 0x510E527FUL, + BLAKE2S_IV5 = 0x9B05688CUL, + BLAKE2S_IV6 = 0x1F83D9ABUL, + BLAKE2S_IV7 = 0x5BE0CD19UL, +}; + +static inline void __blake2s_init(struct blake2s_ctx *ctx, size_t outlen, + const void *key, size_t keylen) +{ + ctx->h[0] = BLAKE2S_IV0 ^ (0x01010000 | keylen << 8 | outlen); + ctx->h[1] = BLAKE2S_IV1; + ctx->h[2] = BLAKE2S_IV2; + ctx->h[3] = BLAKE2S_IV3; + ctx->h[4] = BLAKE2S_IV4; + ctx->h[5] = BLAKE2S_IV5; + ctx->h[6] = BLAKE2S_IV6; + ctx->h[7] = BLAKE2S_IV7; + ctx->t[0] = 0; + ctx->t[1] = 0; + ctx->f[0] = 0; + ctx->f[1] = 0; + ctx->buflen = 0; + ctx->outlen = outlen; + if (keylen) { + memcpy(ctx->buf, key, keylen); + memset(&ctx->buf[keylen], 0, BLAKE2S_BLOCK_SIZE - keylen); + ctx->buflen = BLAKE2S_BLOCK_SIZE; + } +} + +static inline void blake2s_init(struct blake2s_ctx *ctx, size_t outlen) +{ + __blake2s_init(ctx, outlen, NULL, 0); +} + +static inline void blake2s_init_key(struct blake2s_ctx *ctx, size_t outlen, + const void *key, size_t keylen) +{ + __blake2s_init(ctx, outlen, key, keylen); +} + +void blake2s_update(struct blake2s_ctx *ctx, const u8 *in, size_t inlen); + +void blake2s_final(struct blake2s_ctx *ctx, u8 *out); + +#endif /* _CRYPTO_BLAKE2S_H */ -- cgit v1.3.1