y2038: x86: Extend sysvipc data structures
authorArnd Bergmann <arnd@arndb.de>
Tue, 5 May 2015 21:05:19 +0000 (23:05 +0200)
committerArnd Bergmann <arnd@arndb.de>
Fri, 20 Apr 2018 14:19:52 +0000 (16:19 +0200)
This extends the x86 copy of the sysvipc data structures to deal with
32-bit user space that has 64-bit time_t and wants to see timestamps
beyond 2038.

Fortunately, x86 has padding for this purpose in all the data structures,
so we can just add extra fields. With msgid64_ds and shmid64_ds, the
data structure is identical to the asm-generic version, which we have
already extended.

For some reason however, the 64-bit version of semid64_ds ended up with
extra padding, so I'm implementing the same approach as the asm-generic
version here, by using separate fields for the upper and lower halves
of the two timestamps.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
arch/x86/include/asm/compat.h
arch/x86/include/uapi/asm/sembuf.h

index 7cd314b71c513154c2e13253791898c5c4807319..fb97cf7c4137185a88b2af1846d914dc08de7120 100644 (file)
@@ -134,10 +134,10 @@ struct compat_ipc64_perm {
 
 struct compat_semid64_ds {
        struct compat_ipc64_perm sem_perm;
-       compat_time_t  sem_otime;
-       compat_ulong_t __unused1;
-       compat_time_t  sem_ctime;
-       compat_ulong_t __unused2;
+       compat_ulong_t sem_otime;
+       compat_ulong_t sem_otime_high;
+       compat_ulong_t sem_ctime;
+       compat_ulong_t sem_ctime_high;
        compat_ulong_t sem_nsems;
        compat_ulong_t __unused3;
        compat_ulong_t __unused4;
@@ -145,12 +145,12 @@ struct compat_semid64_ds {
 
 struct compat_msqid64_ds {
        struct compat_ipc64_perm msg_perm;
-       compat_time_t  msg_stime;
-       compat_ulong_t __unused1;
-       compat_time_t  msg_rtime;
-       compat_ulong_t __unused2;
-       compat_time_t  msg_ctime;
-       compat_ulong_t __unused3;
+       compat_ulong_t msg_stime;
+       compat_ulong_t msg_stime_high;
+       compat_ulong_t msg_rtime;
+       compat_ulong_t msg_rtime_high;
+       compat_ulong_t msg_ctime;
+       compat_ulong_t msg_ctime_high;
        compat_ulong_t msg_cbytes;
        compat_ulong_t msg_qnum;
        compat_ulong_t msg_qbytes;
@@ -163,12 +163,12 @@ struct compat_msqid64_ds {
 struct compat_shmid64_ds {
        struct compat_ipc64_perm shm_perm;
        compat_size_t  shm_segsz;
-       compat_time_t  shm_atime;
-       compat_ulong_t __unused1;
-       compat_time_t  shm_dtime;
-       compat_ulong_t __unused2;
-       compat_time_t  shm_ctime;
-       compat_ulong_t __unused3;
+       compat_ulong_t shm_atime;
+       compat_ulong_t shm_atime_high;
+       compat_ulong_t shm_dtime;
+       compat_ulong_t shm_dtime_high;
+       compat_ulong_t shm_ctime;
+       compat_ulong_t shm_ctime_high;
        compat_pid_t   shm_cpid;
        compat_pid_t   shm_lpid;
        compat_ulong_t shm_nattch;
index cabd7476bd6c3efa2e0603e9e421a96892dc9dcf..89de6cd9f0a778408600d51849caa3ee8971f93a 100644 (file)
@@ -8,15 +8,24 @@
  * between kernel and user space.
  *
  * Pad space is left for:
- * - 64-bit time_t to solve y2038 problem
  * - 2 miscellaneous 32-bit values
+ *
+ * x86_64 and x32 incorrectly added padding here, so the structures
+ * are still incompatible with the padding on x86.
  */
 struct semid64_ds {
        struct ipc64_perm sem_perm;     /* permissions .. see ipc.h */
+#ifdef __i386__
+       unsigned long   sem_otime;      /* last semop time */
+       unsigned long   sem_otime_high;
+       unsigned long   sem_ctime;      /* last change time */
+       unsigned long   sem_ctime_high;
+#else
        __kernel_time_t sem_otime;      /* last semop time */
        __kernel_ulong_t __unused1;
        __kernel_time_t sem_ctime;      /* last change time */
        __kernel_ulong_t __unused2;
+#endif
        __kernel_ulong_t sem_nsems;     /* no. of semaphores in array */
        __kernel_ulong_t __unused3;
        __kernel_ulong_t __unused4;