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 --- net/atm/common.h | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 net/atm/common.h (limited to 'net/atm/common.h') diff --git a/net/atm/common.h b/net/atm/common.h new file mode 100644 index 000000000..11cb51dd7 --- /dev/null +++ b/net/atm/common.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* net/atm/common.h - ATM sockets (common part for PVC and SVC) */ + +/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */ + + +#ifndef NET_ATM_COMMON_H +#define NET_ATM_COMMON_H + +#include +#include /* for poll_table */ + + +int vcc_create(struct net *net, struct socket *sock, int protocol, int family, int kern); +int vcc_release(struct socket *sock); +int vcc_connect(struct socket *sock, int itf, short vpi, int vci); +int vcc_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags); +int vcc_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len); +__poll_t vcc_poll(struct file *file, struct socket *sock, poll_table *wait); +int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg); +int vcc_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg); +int vcc_setsockopt(struct socket *sock, int level, int optname, + sockptr_t optval, unsigned int optlen); +int vcc_getsockopt(struct socket *sock, int level, int optname, + sockopt_t *opt); +void vcc_process_recv_queue(struct atm_vcc *vcc); + +int atmpvc_init(void); +void atmpvc_exit(void); +int atm_sysfs_init(void); +void atm_sysfs_exit(void); + +#ifdef CONFIG_PROC_FS +int atm_proc_init(void); +void atm_proc_exit(void); +#else +static inline int atm_proc_init(void) +{ + return 0; +} + +static inline void atm_proc_exit(void) +{ + /* nothing */ +} +#endif /* CONFIG_PROC_FS */ + +void atm_dev_release_vccs(struct atm_dev *dev); + +#endif -- cgit v1.3.1