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| author | Ali Ahmet Memis <ali@iusegentoo.com> | 2026-08-21 01:45:27 +0000 |
|---|---|---|
| committer | Stafford Horne <shorne@gmail.com> | 2026-08-29 07:32:26 +0100 |
| commit | 78004e9a87f240df03e2f73120d291763c32e0a7 (patch) | |
| tree | 137c22dd795222931b9d2bf2501d37cd766741aa /include/net/failover.h | |
| download | linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.tar.gz linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.zip | |
openrisc: fix arbitrary kernel memory access via or1k_atomic syscallgrafted
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 <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Diffstat (limited to 'include/net/failover.h')
| -rw-r--r-- | include/net/failover.h | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/include/net/failover.h b/include/net/failover.h new file mode 100644 index 000000000..f2b42b4b9 --- /dev/null +++ b/include/net/failover.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (c) 2018, Intel Corporation. */ + +#ifndef _FAILOVER_H +#define _FAILOVER_H + +#include <linux/netdevice.h> + +struct failover_ops { + int (*slave_pre_register)(struct net_device *slave_dev, + struct net_device *failover_dev); + int (*slave_register)(struct net_device *slave_dev, + struct net_device *failover_dev); + int (*slave_pre_unregister)(struct net_device *slave_dev, + struct net_device *failover_dev); + int (*slave_unregister)(struct net_device *slave_dev, + struct net_device *failover_dev); + int (*slave_link_change)(struct net_device *slave_dev, + struct net_device *failover_dev); + int (*slave_name_change)(struct net_device *slave_dev, + struct net_device *failover_dev); + rx_handler_result_t (*slave_handle_frame)(struct sk_buff **pskb); +}; + +struct failover { + struct list_head list; + struct net_device __rcu *failover_dev; + netdevice_tracker dev_tracker; + struct failover_ops __rcu *ops; +}; + +struct failover *failover_register(struct net_device *dev, + struct failover_ops *ops); +void failover_unregister(struct failover *failover); +int failover_slave_unregister(struct net_device *slave_dev); + +#endif /* _FAILOVER_H */ |