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/stats.h | 73 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 fs/smb/server/stats.h (limited to 'fs/smb/server/stats.h') diff --git a/fs/smb/server/stats.h b/fs/smb/server/stats.h new file mode 100644 index 000000000..b60c30c69 --- /dev/null +++ b/fs/smb/server/stats.h @@ -0,0 +1,73 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2025, LG Electronics. + * Author(s): Hyunchul Lee + * Copyright (C) 2025, Samsung Electronics. + * Author(s): Vedansh Bhardwaj + */ + +#ifndef __KSMBD_STATS_H__ +#define __KSMBD_STATS_H__ + +#define KSMBD_COUNTER_MAX_REQS 19 + +enum { + KSMBD_COUNTER_SESSIONS = 0, + KSMBD_COUNTER_TREE_CONNS, + KSMBD_COUNTER_REQUESTS, + KSMBD_COUNTER_READ_BYTES, + KSMBD_COUNTER_WRITE_BYTES, + KSMBD_COUNTER_FIRST_REQ, + KSMBD_COUNTER_LAST_REQ = KSMBD_COUNTER_FIRST_REQ + + KSMBD_COUNTER_MAX_REQS - 1, + KSMBD_COUNTER_MAX, +}; + +#ifdef CONFIG_PROC_FS +extern struct ksmbd_counters ksmbd_counters; + +struct ksmbd_counters { + struct percpu_counter counters[KSMBD_COUNTER_MAX]; +}; + +static inline void ksmbd_counter_inc(int type) +{ + percpu_counter_inc(&ksmbd_counters.counters[type]); +} + +static inline void ksmbd_counter_dec(int type) +{ + percpu_counter_dec(&ksmbd_counters.counters[type]); +} + +static inline void ksmbd_counter_add(int type, s64 value) +{ + percpu_counter_add(&ksmbd_counters.counters[type], value); +} + +static inline void ksmbd_counter_sub(int type, s64 value) +{ + percpu_counter_sub(&ksmbd_counters.counters[type], value); +} + +static inline void ksmbd_counter_inc_reqs(unsigned int cmd) +{ + if (cmd < KSMBD_COUNTER_MAX_REQS) + percpu_counter_inc(&ksmbd_counters.counters[KSMBD_COUNTER_FIRST_REQ + cmd]); +} + +static inline s64 ksmbd_counter_sum(int type) +{ + return percpu_counter_sum_positive(&ksmbd_counters.counters[type]); +} +#else + +static inline void ksmbd_counter_inc(int type) {} +static inline void ksmbd_counter_dec(int type) {} +static inline void ksmbd_counter_add(int type, s64 value) {} +static inline void ksmbd_counter_sub(int type, s64 value) {} +static inline void ksmbd_counter_inc_reqs(unsigned int cmd) {} +static inline s64 ksmbd_counter_sum(int type) { return 0; } +#endif + +#endif -- cgit v1.3.1