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/md/md-cluster.h | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 drivers/md/md-cluster.h (limited to 'drivers/md/md-cluster.h') diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h new file mode 100644 index 000000000..8fb06d853 --- /dev/null +++ b/drivers/md/md-cluster.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + + +#ifndef _MD_CLUSTER_H +#define _MD_CLUSTER_H + +#include "md.h" + +struct mddev; +struct md_rdev; + +struct md_cluster_operations { + struct md_submodule_head head; + + int (*join)(struct mddev *mddev, int nodes); + int (*leave)(struct mddev *mddev); + int (*slot_number)(struct mddev *mddev); + int (*resync_info_update)(struct mddev *mddev, sector_t lo, sector_t hi); + int (*resync_start_notify)(struct mddev *mddev); + int (*resync_status_get)(struct mddev *mddev); + void (*resync_info_get)(struct mddev *mddev, sector_t *lo, sector_t *hi); + int (*metadata_update_start)(struct mddev *mddev); + int (*metadata_update_finish)(struct mddev *mddev); + void (*metadata_update_cancel)(struct mddev *mddev); + int (*resync_start)(struct mddev *mddev); + int (*resync_finish)(struct mddev *mddev); + int (*area_resyncing)(struct mddev *mddev, int direction, sector_t lo, sector_t hi); + int (*add_new_disk)(struct mddev *mddev, struct md_rdev *rdev); + void (*add_new_disk_cancel)(struct mddev *mddev); + int (*new_disk_ack)(struct mddev *mddev, bool ack); + int (*remove_disk)(struct mddev *mddev, struct md_rdev *rdev); + void (*load_bitmaps)(struct mddev *mddev, int total_slots); + int (*gather_bitmaps)(struct md_rdev *rdev); + int (*resize_bitmaps)(struct mddev *mddev, sector_t newsize, sector_t oldsize); + int (*lock_all_bitmaps)(struct mddev *mddev); + void (*unlock_all_bitmaps)(struct mddev *mddev); + void (*update_size)(struct mddev *mddev, sector_t old_dev_sectors); +}; + +extern int md_setup_cluster(struct mddev *mddev, int nodes); +extern void md_cluster_stop(struct mddev *mddev); +extern void md_reload_sb(struct mddev *mddev, int raid_disk); + +#endif /* _MD_CLUSTER_H */ -- cgit v1.3.1