[PATCH 5.2 36/85] ipc: fix sparc64 ipc() wrapper

Greg Kroah-Hartman
2019-09-18T06:29:49Z

From: Arnd Bergmann <arnd@arndb.de>

commit fb377eb80c80339b580831a3c0fcce34a4c9d1ad upstream.

Matt bisected a sparc64 specific issue with semctl, shmctl and msgctl
to a commit from my y2038 series in linux-5.1, as I missed the custom
sys_ipc() wrapper that sparc64 uses in place of the generic version that
I patched.

The problem is that the sys_{sem,shm,msg}ctl() functions in the kernel
now do not allow being called with the IPC_64 flag any more, resulting
in a -EINVAL error when they don't recognize the command.

Instead, the correct way to do this now is to call the internal
ksys_old_{sem,shm,msg}ctl() functions to select the API version.

As we generally move towards these functions anyway, change all of
sparc_ipc() to consistently use those in place of the sys_*() versions,
and move the required ksys_*() declarations into linux/syscalls.h

The IS_ENABLED(CONFIG_SYSVIPC) check is required to avoid link
errors when ipc is disabled.

Reported-by: Matt Turner <mattst88@gmail.com>
Fixes: 275f22148e87 ("ipc: rename old-style shmctl/semctl/msgctl syscalls")
Cc: stable@vger.kernel.org
Tested-by: Matt Turner <mattst88@gmail.com>
Tested-by: Anatoly Pugachev <matorola@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/sparc/kernel/sys_sparc_64.c | 33 ++++++++++++++++++---------------
include/linux/syscalls.h | 19 +++++++++++++++++++
ipc/util.h | 25 ++-----------------------
3 files changed, 39 insertions(+), 38 deletions(-)

--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -336,25 +336,28 @@ SYSCALL_DEFINE6(sparc_ipc, unsigned int,
{
long err;

+ if (!IS_ENABLED(CONFIG_SYSVIPC))
+ return -ENOSYS;
+
/* No need for backward compatibility. We can start fresh... */
if (call <= SEMTIMEDOP) {
switch (call) {
case SEMOP:
- err = sys_semtimedop(first, ptr,
- (unsigned int)second, NULL);
+ err = ksys_semtimedop(first, ptr,
+ (unsigned int)second, NULL);
goto out;
case SEMTIMEDOP:
- err = sys_semtimedop(first, ptr, (unsigned int)second,
+ err = ksys_semtimedop(first, ptr, (unsigned int)second,
(const struct __kernel_timespec __user *)
- (unsigned long) fifth);
+ (unsigned long) fifth);
goto out;
case SEMGET:
- err = sys_semget(first, (int)second, (int)third);
+ err = ksys_semget(first, (int)second, (int)third);
goto out;
case SEMCTL: {
- err = sys_semctl(first, second,
- (int)third | IPC_64,
- (unsigned long) ptr);
+ err = ksys_old_semctl(first, second,
+ (int)third | IPC_64,
+ (unsigned long) ptr);
goto out;
}
default:
@@ -365,18 +368,18 @@ SYSCALL_DEFINE6(sparc_ipc, unsigned int,
if (call <= MSGCTL) {
switch (call) {
case MSGSND:
- err = sys_msgsnd(first, ptr, (size_t)second,
+ err = ksys_msgsnd(first, ptr, (size_t)second,
(int)third);
goto out;
case MSGRCV:
- err = sys_msgrcv(first, ptr, (size_t)second, fifth,
+ err = ksys_msgrcv(first, ptr, (size_t)second, fifth,
(int)third);
goto out;
case MSGGET:
- err = sys_msgget((key_t)first, (int)second);
+ err = ksys_msgget((key_t)first, (int)second);
goto out;
case MSGCTL:
- err = sys_msgctl(first, (int)second | IPC_64, ptr);
+ err = ksys_old_msgctl(first, (int)second | IPC_64, ptr);
goto out;
default:
err = -ENOSYS;
@@ -396,13 +399,13 @@ SYSCALL_DEFINE6(sparc_ipc, unsigned int,
goto out;
}
case SHMDT:
- err = sys_shmdt(ptr);
+ err = ksys_shmdt(ptr);
goto out;
case SHMGET:
- err = sys_shmget(first, (size_t)second, (int)third);
+ err = ksys_shmget(first, (size_t)second, (int)third);
goto out;
case SHMCTL:
- err = sys_shmctl(first, (int)second | IPC_64, ptr);
+ err = ksys_old_shmctl(first, (int)second | IPC_64, ptr);
goto out;
default:
err = -ENOSYS;
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -1397,4 +1397,23 @@ static inline unsigned int ksys_personal
return old;
}

+/* for __ARCH_WANT_SYS_IPC */
+long ksys_semtimedop(int semid, struct sembuf __user *tsops,
+ unsigned int nsops,
+ const struct __kernel_timespec __user *timeout);
+long ksys_semget(key_t key, int nsems, int semflg);
+long ksys_old_semctl(int semid, int semnum, int cmd, unsigned long arg);
+long ksys_msgget(key_t key, int msgflg);
+long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf);
+long ksys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz,
+ long msgtyp, int msgflg);
+long ksys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz,
+ int msgflg);
+long ksys_shmget(key_t key, size_t size, int shmflg);
+long ksys_shmdt(char __user *shmaddr);
+long ksys_old_shmctl(int shmid, int cmd, struct shmid_ds __user *buf);
+long compat_ksys_semtimedop(int semid, struct sembuf __user *tsems,
+ unsigned int nsops,
+ const struct old_timespec32 __user *timeout);
+
#endif
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -276,29 +276,7 @@ static inline int compat_ipc_parse_versi
*cmd &= ~IPC_64;
return version;
}
-#endif
-
-/* for __ARCH_WANT_SYS_IPC */
-long ksys_semtimedop(int semid, struct sembuf __user *tsops,
- unsigned int nsops,
- const struct __kernel_timespec __user *timeout);
-long ksys_semget(key_t key, int nsems, int semflg);
-long ksys_old_semctl(int semid, int semnum, int cmd, unsigned long arg);
-long ksys_msgget(key_t key, int msgflg);
-long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf);
-long ksys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz,
- long msgtyp, int msgflg);
-long ksys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz,
- int msgflg);
-long ksys_shmget(key_t key, size_t size, int shmflg);
-long ksys_shmdt(char __user *shmaddr);
-long ksys_old_shmctl(int shmid, int cmd, struct shmid_ds __user *buf);

-/* for CONFIG_ARCH_WANT_OLD_COMPAT_IPC */
-long compat_ksys_semtimedop(int semid, struct sembuf __user *tsems,
- unsigned int nsops,
- const struct old_timespec32 __user *timeout);
-#ifdef CONFIG_COMPAT
long compat_ksys_old_semctl(int semid, int semnum, int cmd, int arg);
long compat_ksys_old_msgctl(int msqid, int cmd, void __user *uptr);
long compat_ksys_msgrcv(int msqid, compat_uptr_t msgp, compat_ssize_t msgsz,
@@ -306,6 +284,7 @@ long compat_ksys_msgrcv(int msqid, compa
long compat_ksys_msgsnd(int msqid, compat_uptr_t msgp,
compat_ssize_t msgsz, int msgflg);
long compat_ksys_old_shmctl(int shmid, int cmd, void __user *uptr);
-#endif /* CONFIG_COMPAT */
+
+#endif

#endif