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/video/fbdev/carminefb.h | 65 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 drivers/video/fbdev/carminefb.h (limited to 'drivers/video/fbdev/carminefb.h') diff --git a/drivers/video/fbdev/carminefb.h b/drivers/video/fbdev/carminefb.h new file mode 100644 index 000000000..c9825481d --- /dev/null +++ b/drivers/video/fbdev/carminefb.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef CARMINE_CARMINE_H +#define CARMINE_CARMINE_H + +#define CARMINE_MEMORY_BAR 2 +#define CARMINE_CONFIG_BAR 3 + +#define MAX_DISPLAY 2 +#define CARMINE_DISPLAY_MEM (800 * 600 * 4) +#define CARMINE_TOTAL_DISPLAY_MEM (CARMINE_DISPLAY_MEM * MAX_DISPLAY) + +#define CARMINE_USE_DISPLAY0 (1 << 0) +#define CARMINE_USE_DISPLAY1 (1 << 1) + +/* + * This values work on the eval card. Custom boards may use different timings, + * here an example :) + */ + +/* DRAM initialization values */ +#ifdef CONFIG_FB_CARMINE_DRAM_EVAL + +#define CARMINE_DFLT_IP_CLOCK_ENABLE (0x03ff) +#define CARMINE_DFLT_IP_DCTL_ADD (0x05c3) +#define CARMINE_DFLT_IP_DCTL_MODE (0x0121) +#define CARMINE_DFLT_IP_DCTL_EMODE (0x8000) +#define CARMINE_DFLT_IP_DCTL_SET_TIME1 (0x4749) +#define CARMINE_DFLT_IP_DCTL_SET_TIME2 (0x2a22) +#define CARMINE_DFLT_IP_DCTL_REFRESH (0x0042) +#define CARMINE_DFLT_IP_DCTL_STATES (0x0003) +#define CARMINE_DFLT_IP_DCTL_RESERVE0 (0x0020) +#define CARMINE_DFLT_IP_DCTL_FIFO_DEPTH (0x000f) +#define CARMINE_DFLT_IP_DCTL_RESERVE2 (0x0000) +#define CARMINE_DFLT_IP_DCTL_DDRIF1 (0x6646) +#define CARMINE_DFLT_IP_DCTL_DDRIF2 (0x0055) +#define CARMINE_DFLT_IP_DCTL_MODE_AFT_RST (0x0021) +#define CARMINE_DFLT_IP_DCTL_STATES_AFT_RST (0x0002) +#define CARMINE_DFLT_IP_DCTL_IO_CONT0 (0x0555) +#define CARMINE_DFLT_IP_DCTL_IO_CONT1 (0x0555) +#define CARMINE_DCTL_DLL_RESET (1) +#endif + +#ifdef CONFIG_CARMINE_DRAM_CUSTOM + +#define CARMINE_DFLT_IP_CLOCK_ENABLE (0x03ff) +#define CARMINE_DFLT_IP_DCTL_ADD (0x03b2) +#define CARMINE_DFLT_IP_DCTL_MODE (0x0161) +#define CARMINE_DFLT_IP_DCTL_EMODE (0x8000) +#define CARMINE_DFLT_IP_DCTL_SET_TIME1 (0x2628) +#define CARMINE_DFLT_IP_DCTL_SET_TIME2 (0x1a09) +#define CARMINE_DFLT_IP_DCTL_REFRESH (0x00fe) +#define CARMINE_DFLT_IP_DCTL_STATES (0x0003) +#define CARMINE_DFLT_IP_DCTL_RESERVE0 (0x0020) +#define CARMINE_DFLT_IP_DCTL_FIFO_DEPTH (0x000f) +#define CARMINE_DFLT_IP_DCTL_RESERVE2 (0x0000) +#define CARMINE_DFLT_IP_DCTL_DDRIF1 (0x0646) +#define CARMINE_DFLT_IP_DCTL_DDRIF2 (0x55aa) +#define CARMINE_DFLT_IP_DCTL_MODE_AFT_RST (0x0061) +#define CARMINE_DFLT_IP_DCTL_STATES_AFT_RST (0x0002) +#define CARMINE_DFLT_IP_DCTL_IO_CONT0 (0x0555) +#define CARMINE_DFLT_IP_DCTL_IO_CONT1 (0x0555) +#define CARMINE_DCTL_DLL_RESET (1) +#endif + +#endif -- cgit v1.3.1