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 --- drivers/rtc/rtc-s3c.h | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 drivers/rtc/rtc-s3c.h (limited to 'drivers/rtc/rtc-s3c.h') diff --git a/drivers/rtc/rtc-s3c.h b/drivers/rtc/rtc-s3c.h new file mode 100644 index 000000000..11d7a1255 --- /dev/null +++ b/drivers/rtc/rtc-s3c.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2003 Simtec Electronics + * http://www.simtec.co.uk/products/SWLINUX/ + * + * S3C2410 Internal RTC register definition +*/ + +#ifndef __ASM_ARCH_REGS_RTC_H +#define __ASM_ARCH_REGS_RTC_H __FILE__ + +#define S3C2410_RTCREG(x) (x) +#define S3C2410_INTP S3C2410_RTCREG(0x30) +#define S3C2410_INTP_ALM (1 << 1) +#define S3C2410_INTP_TIC (1 << 0) + +#define S3C2410_RTCCON S3C2410_RTCREG(0x40) +#define S3C2410_RTCCON_RTCEN (1 << 0) +#define S3C2410_RTCCON_CNTSEL (1 << 2) +#define S3C2410_RTCCON_CLKRST (1 << 3) +#define S3C2443_RTCCON_TICSEL (1 << 4) +#define S3C64XX_RTCCON_TICEN (1 << 8) + +#define S3C2410_RTCALM S3C2410_RTCREG(0x50) +#define S3C2410_RTCALM_ALMEN (1 << 6) +#define S3C2410_RTCALM_YEAREN (1 << 5) +#define S3C2410_RTCALM_MONEN (1 << 4) +#define S3C2410_RTCALM_DAYEN (1 << 3) +#define S3C2410_RTCALM_HOUREN (1 << 2) +#define S3C2410_RTCALM_MINEN (1 << 1) +#define S3C2410_RTCALM_SECEN (1 << 0) + +#define S3C2410_ALMSEC S3C2410_RTCREG(0x54) +#define S3C2410_ALMMIN S3C2410_RTCREG(0x58) +#define S3C2410_ALMHOUR S3C2410_RTCREG(0x5c) + +#define S3C2410_ALMDATE S3C2410_RTCREG(0x60) +#define S3C2410_ALMMON S3C2410_RTCREG(0x64) +#define S3C2410_ALMYEAR S3C2410_RTCREG(0x68) + +#define S3C2410_RTCSEC S3C2410_RTCREG(0x70) +#define S3C2410_RTCMIN S3C2410_RTCREG(0x74) +#define S3C2410_RTCHOUR S3C2410_RTCREG(0x78) +#define S3C2410_RTCDATE S3C2410_RTCREG(0x7c) +#define S3C2410_RTCMON S3C2410_RTCREG(0x84) +#define S3C2410_RTCYEAR S3C2410_RTCREG(0x88) + +#endif /* __ASM_ARCH_REGS_RTC_H */ -- cgit v1.3.1