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 --- fs/crypto/Kconfig | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 fs/crypto/Kconfig (limited to 'fs/crypto/Kconfig') diff --git a/fs/crypto/Kconfig b/fs/crypto/Kconfig new file mode 100644 index 000000000..983d8ad1f --- /dev/null +++ b/fs/crypto/Kconfig @@ -0,0 +1,40 @@ +# SPDX-License-Identifier: GPL-2.0-only +config FS_ENCRYPTION + bool "FS Encryption (Per-file encryption)" + select CRYPTO + select CRYPTO_SKCIPHER + select CRYPTO_LIB_AES + select CRYPTO_LIB_SHA256 + select CRYPTO_LIB_SHA512 + select KEYS + help + Enable encryption of files and directories. This + feature is similar to ecryptfs, but it is more memory + efficient since it avoids caching the encrypted and + decrypted pages in the page cache. Currently Ext4, + F2FS, UBIFS, and CephFS make use of this feature. + +# Filesystems supporting encryption must select this if FS_ENCRYPTION. This +# allows the algorithms to be built as modules when all the filesystems are, +# whereas selecting them from FS_ENCRYPTION would force them to be built-in. +# +# Note: this option only pulls in the algorithms that filesystem encryption +# needs "by default". If userspace will use "non-default" encryption modes such +# as Adiantum encryption, then those other modes need to be explicitly enabled +# in the crypto API; see Documentation/filesystems/fscrypt.rst for details. +# +# Also note that this option only pulls in the generic implementations of the +# algorithms, not any per-architecture optimized implementations. It is +# strongly recommended to enable optimized implementations too. +config FS_ENCRYPTION_ALGS + tristate + select CRYPTO_AES + select CRYPTO_CBC + select CRYPTO_CTS + select CRYPTO_XTS + +config FS_ENCRYPTION_INLINE_CRYPT + bool "Enable fscrypt to use inline crypto" + depends on FS_ENCRYPTION && BLK_INLINE_ENCRYPTION + help + Enable fscrypt to use inline encryption hardware if available. -- cgit v1.3.1