Hello, David. Here are two fixes for the ia32-compatibility mode handling
for the new semtimedop() system call for the ia64 architecture.
The first problem was that treatment of user-mode calls to semtimedop()
with a NULL 4th (struct timespec *) parameter was inconsistent with the
behavior of the same executable on i386 and also with a natively compiled
ia64 binary. A NULL 4th arg to semtimedop() should result in no timeout
being used (like a straight semop() call) rather than in an EFAULT error.
The second problem was that a legitimate semtimedop() with a timeout was
also resulting in an EFAULT because the fetch of the internal timespec
strucure by sys_semtimedop() from semtimedop32()'s kernel stack was
treated as an invalid user-data reference. This requires temporarily
switching the addressing limit with set_fs(), further requiring that
appropriate parameter checking by performed prior to the switch.
The const qualifier was removed from the (struct compat_timespec *) arg
to semtimedop32() so that the call to get_compat_timespec() wouldn't
generate a compilation warning.
Cheers. -ernie
diff -urpN linux-2.5.68/arch/ia64/ia32/sys_ia32.c{.orig,}
--- linux-2.5.68/arch/ia64/ia32/sys_ia32.c.orig 2003-04-19 22:50:02.000000000 -0400
+++ linux-2.5.68/arch/ia64/ia32/sys_ia32.c 2003-04-28 01:12:41.000000000 -0400
@@ -1648,19 +1648,35 @@ shmctl32 (int first, int second, void *u
return err;
}
+extern int sem_ctls[];
+#define sc_semopm (sem_ctls[2])
+
static long
-semtimedop32(int semid, struct sembuf *tsems, int nsems,
- const struct compat_timespec *timeout32)
+semtimedop32(int semid, struct sembuf *tsops, int nsops,
+ struct compat_timespec *timeout32)
{
struct timespec t;
- if (get_user (t.tv_sec, &timeout32->tv_sec) ||
- get_user (t.tv_nsec, &timeout32->tv_nsec))
+ mm_segment_t oldfs;
+ long ret;
+
+ /* parameter checking precedence should mirror sys_semtimedop() */
+ if (nsops < 1 || semid < 0)
+ return -EINVAL;
+ if (nsops > sc_semopm)
+ return -E2BIG;
+ if (!access_ok(VERIFY_READ, tsops, nsops * sizeof(struct sembuf)) ||
+ get_compat_timespec(&t, timeout32))
return -EFAULT;
- return sys_semtimedop(semid, tsems, nsems, &t);
+
+ oldfs = get_fs();
+ set_fs(KERNEL_DS);
+ ret = sys_semtimedop(semid, tsops, nsops, &t);
+ set_fs(oldfs);
+ return ret;
}
asmlinkage long
-sys32_ipc (u32 call, int first, int second, int third, u32 ptr, u32 fifth)
+sys32_ipc(u32 call, int first, int second, int third, u32 ptr, u32 fifth)
{
int version;
@@ -1668,12 +1684,15 @@ sys32_ipc (u32 call, int first, int seco
call &= 0xffff;
switch (call) {
+ case SEMTIMEDOP:
+ if (fifth)
+ return semtimedop32(first, (struct sembuf *)AA(ptr),
+ second, (struct compat_timespec *)AA(fifth));
+ /* else fall through for normal semop() */
case SEMOP:
/* struct sembuf is the same on 32 and 64bit :)) */
- return sys_semtimedop(first, (struct sembuf *)AA(ptr), second, NULL);
- case SEMTIMEDOP:
- return semtimedop32(first, (struct sembuf *)AA(ptr), second,
- (const struct compat_timespec *)AA(fifth));
+ return sys_semtimedop(first, (struct sembuf *)AA(ptr), second,
+ NULL);
case SEMGET:
return sys_semget(first, second, third);
case SEMCTL:
-
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This archive was generated by hypermail 2b29 : Wed Apr 30 2003 - 22:00:28 EST