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 --- include/crypto/cryptd.h | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 include/crypto/cryptd.h (limited to 'include/crypto/cryptd.h') diff --git a/include/crypto/cryptd.h b/include/crypto/cryptd.h new file mode 100644 index 000000000..29c5878a3 --- /dev/null +++ b/include/crypto/cryptd.h @@ -0,0 +1,39 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Software async crypto daemon + * + * Added AEAD support to cryptd. + * Authors: Tadeusz Struk (tadeusz.struk@intel.com) + * Adrian Hoban + * Gabriele Paoloni + * Aidan O'Mahony (aidan.o.mahony@intel.com) + * Copyright (c) 2010, Intel Corporation. + */ + +#ifndef _CRYPTO_CRYPT_H +#define _CRYPTO_CRYPT_H + +#include + +#include + +struct cryptd_aead { + struct crypto_aead base; +}; + +static inline struct cryptd_aead *__cryptd_aead_cast( + struct crypto_aead *tfm) +{ + return (struct cryptd_aead *)tfm; +} + +struct cryptd_aead *cryptd_alloc_aead(const char *alg_name, + u32 type, u32 mask); + +struct crypto_aead *cryptd_aead_child(struct cryptd_aead *tfm); +/* Must be called without moving CPUs. */ +bool cryptd_aead_queued(struct cryptd_aead *tfm); + +void cryptd_free_aead(struct cryptd_aead *tfm); + +#endif -- cgit v1.3.1