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/f2fs/acl.h | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 fs/f2fs/acl.h (limited to 'fs/f2fs/acl.h') diff --git a/fs/f2fs/acl.h b/fs/f2fs/acl.h new file mode 100644 index 000000000..20e87e63c --- /dev/null +++ b/fs/f2fs/acl.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * fs/f2fs/acl.h + * + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * Portions of this code from linux/fs/ext2/acl.h + * + * Copyright (C) 2001-2003 Andreas Gruenbacher, + */ +#ifndef __F2FS_ACL_H__ +#define __F2FS_ACL_H__ + +#include + +#define F2FS_ACL_VERSION 0x0001 + +struct f2fs_acl_entry { + __le16 e_tag; + __le16 e_perm; + __le32 e_id; +}; + +struct f2fs_acl_entry_short { + __le16 e_tag; + __le16 e_perm; +}; + +struct f2fs_acl_header { + __le32 a_version; +}; + +#ifdef CONFIG_F2FS_FS_POSIX_ACL + +struct posix_acl *f2fs_get_acl(struct inode *, int, bool); +int f2fs_set_acl(struct mnt_idmap *, struct dentry *, + struct posix_acl *, int); +int f2fs_init_acl(struct inode *, struct inode *, struct folio *ifolio, + struct folio *dfolio); +#else +#define f2fs_get_acl NULL +#define f2fs_set_acl NULL + +static inline int f2fs_init_acl(struct inode *inode, struct inode *dir, + struct folio *ifolio, struct folio *dfolio) +{ + return 0; +} +#endif +#endif /* __F2FS_ACL_H__ */ -- cgit v1.3.1