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/smb/server/unicode.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 fs/smb/server/unicode.h (limited to 'fs/smb/server/unicode.h') diff --git a/fs/smb/server/unicode.h b/fs/smb/server/unicode.h new file mode 100644 index 000000000..28c7c736f --- /dev/null +++ b/fs/smb/server/unicode.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Some of the source code in this file came from fs/cifs/cifs_unicode.c + * cifs_unicode: Unicode kernel case support + * + * Function: + * Convert a unicode character to upper or lower case using + * compressed tables. + * + * Copyright (c) International Business Machines Corp., 2000,2009 + * + * + * Notes: + * These APIs are based on the C library functions. The semantics + * should match the C functions but with expanded size operands. + * + * The upper/lower functions are based on a table created by mkupr. + * This is a compressed table of upper and lower case conversion. + * + */ +#ifndef _SMB_UNICODE_H +#define _SMB_UNICODE_H + +#include +#include +#include +#include +#include "../../nls/nls_ucs2_utils.h" + +#ifdef __KERNEL__ +int smb_strtoUTF16(__le16 *to, const char *from, int len, + const struct nls_table *codepage); +char *smb_strndup_from_utf16(const char *src, const int maxlen, + const bool is_unicode, + const struct nls_table *codepage); +int smbConvertToUTF16(__le16 *target, const char *source, int srclen, + const struct nls_table *cp, int mapchars); +char *ksmbd_extract_sharename(struct unicode_map *um, const char *treename); +#endif + +#endif /* _SMB_UNICODE_H */ -- cgit v1.3.1