Linux: Support __IPC_64 in sysvctl *ctl command arguments (bug 29771)

Old applications pass __IPC_64 as part of the command argument because
old glibc did not check for unknown commands, and passed through the
arguments directly to the kernel, without adding __IPC_64.
Applications need to continue doing that for old glibc compatibility,
so this commit enables this approach in current glibc.

For msgctl and shmctl, if no translation is required, make
direct system calls, as we did before the time64 changes.  If
translation is required, mask __IPC_64 from the command argument.

For semctl, the union-in-vararg argument handling means that
translation is needed on all architectures.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit 22a46dee24351fd5f4f188ad80554cad79c82524)

diff --git a/NEWS b/NEWS
index ed59136e558e14333f398abe11525ebad98f69d4..1864714d29fa933caee7c0e04370fa916be7a503 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -709,6 +709,7 @@ The following bugs are resolved with this release:
   [27237] malloc: deadlock in malloc/tst-malloc-stats-cancellation
   [27256] locale: Assertion failure in ISO-2022-JP-3 gconv module
     related to combining characters (CVE-2021-3326)
+  [29771] Restore IPC_64 support in sysvipc *ctl functions
 
 \f
 Version 2.32

diff --git a/sysdeps/unix/sysv/linux/ipc_priv.h b/sysdeps/unix/sysv/linux/ipc_priv.h
index f9852367a466cea9c1ae424186801a03e823d4f5..d4efb9f3483daa9f53febcf87e39cc283f943ea2 100644 (file)
--- a/sysdeps/unix/sysv/linux/ipc_priv.h
+++ b/sysdeps/unix/sysv/linux/ipc_priv.h
@@ -63,4 +63,10 @@ struct __old_ipc_perm
 # define __IPC_TIME64 0
 #endif
 
+#if __IPC_TIME64 || defined __ASSUME_SYSVIPC_BROKEN_MODE_T
+# define IPC_CTL_NEED_TRANSLATION 1
+#else
+# define IPC_CTL_NEED_TRANSLATION 0
+#endif
+
 #include <ipc_ops.h>

diff --git a/sysdeps/unix/sysv/linux/msgctl.c b/sysdeps/unix/sysv/linux/msgctl.c
index 9f38c06d539363907995748deaeb29f7aa297210..ba7b94c22d17bc7f443f12d794be6b2c2493dbf5 100644 (file)
--- a/sysdeps/unix/sysv/linux/msgctl.c
+++ b/sysdeps/unix/sysv/linux/msgctl.c
@@ -86,11 +86,19 @@ msgctl_syscall (int msqid, int cmd, msgctl_arg_t *buf)
 int
 __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf)
 {
-#if __IPC_TIME64
+#if IPC_CTL_NEED_TRANSLATION
+# if __IPC_TIME64
   struct kernel_msqid64_ds ksemid, *arg = NULL;
-#else
+# else
   msgctl_arg_t *arg;
-#endif
+# endif
+
+  /* Some applications pass the __IPC_64 flag in cmd, to invoke
+     previously unsupported commands back when there was no EINVAL
+     error checking in glibc.  Mask the flag for the switch statements
+     below.  msgctl_syscall adds back the __IPC_64 flag for the actual
+     system call.  */
+  cmd &= ~__IPC_64;
 
   switch (cmd)
     {
@@ -102,19 +110,19 @@ __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf)
     case IPC_STAT:
     case MSG_STAT:
     case MSG_STAT_ANY:
-#if __IPC_TIME64
+# if __IPC_TIME64
       if (buf != NULL)
        {
          msqid64_to_kmsqid64 (buf, &ksemid);
          arg = &ksemid;
        }
-# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
+#  ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
       if (cmd == IPC_SET)
        arg->msg_perm.mode *= 0x10000U;
-# endif
-#else
+#  endif
+# else
       arg = buf;
-#endif
+# endif
       break;
 
     case IPC_INFO:
@@ -138,21 +146,25 @@ __msgctl64 (int msqid, int cmd, struct __msqid64_ds *buf)
     case IPC_STAT:
     case MSG_STAT:
     case MSG_STAT_ANY:
-#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
+# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
       arg->msg_perm.mode >>= 16;
-#else
+# else
       /* Old Linux kernel versions might not clear the mode padding.  */
       if (sizeof ((struct msqid_ds){0}.msg_perm.mode)
           != sizeof (__kernel_mode_t))
        arg->msg_perm.mode &= 0xFFFF;
-#endif
+# endif
 
-#if __IPC_TIME64
+# if __IPC_TIME64
       kmsqid64_to_msqid64 (arg, buf);
-#endif
+# endif
     }
 
   return ret;
+
+#else /* !IPC_CTL_NEED_TRANSLATION */
+  return msgctl_syscall (msqid, cmd, buf);
+#endif
 }
 #if __TIMESIZE != 64
 libc_hidden_def (__msgctl64)

diff --git a/sysdeps/unix/sysv/linux/semctl.c b/sysdeps/unix/sysv/linux/semctl.c
index bb2690d30f80bb2233bf8557e9c9e9a265376477..97fa411547fdd81ee15cec7a2b0c110e02061c0f 100644 (file)
--- a/sysdeps/unix/sysv/linux/semctl.c
+++ b/sysdeps/unix/sysv/linux/semctl.c
@@ -141,6 +141,13 @@ __semctl64 (int semid, int semnum, int cmd, ...)
   union semun64 arg64 = { 0 };
   va_list ap;
 
+  /* Some applications pass the __IPC_64 flag in cmd, to invoke
+     previously unsupported commands back when there was no EINVAL
+     error checking in glibc.  Mask the flag for the switch statements
+     below.  semctl_syscall adds back the __IPC_64 flag for the actual
+     system call.  */
+  cmd &= ~__IPC_64;
+
   /* Get the argument only if required.  */
   switch (cmd)
     {

diff --git a/sysdeps/unix/sysv/linux/shmctl.c b/sysdeps/unix/sysv/linux/shmctl.c
index f52018bfae4b33647ec344608972d71150fac798..c44cbd6e4ac890a5e31b983894e32afab7890ba1 100644 (file)
--- a/sysdeps/unix/sysv/linux/shmctl.c
+++ b/sysdeps/unix/sysv/linux/shmctl.c
@@ -86,11 +86,19 @@ shmctl_syscall (int shmid, int cmd, shmctl_arg_t *buf)
 int
 __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf)
 {
-#if __IPC_TIME64
+#if IPC_CTL_NEED_TRANSLATION
+# if __IPC_TIME64
   struct kernel_shmid64_ds kshmid, *arg = NULL;
-#else
+# else
   shmctl_arg_t *arg;
-#endif
+# endif
+
+  /* Some applications pass the __IPC_64 flag in cmd, to invoke
+     previously unsupported commands back when there was no EINVAL
+     error checking in glibc.  Mask the flag for the switch statements
+     below.  shmctl_syscall adds back the __IPC_64 flag for the actual
+     system call.  */
+  cmd &= ~__IPC_64;
 
   switch (cmd)
     {
@@ -104,19 +112,19 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf)
     case IPC_STAT:
     case SHM_STAT:
     case SHM_STAT_ANY:
-#if __IPC_TIME64
+# if __IPC_TIME64
       if (buf != NULL)
        {
          shmid64_to_kshmid64 (buf, &kshmid);
          arg = &kshmid;
        }
-# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
+#  ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
       if (cmd == IPC_SET)
         arg->shm_perm.mode *= 0x10000U;
-# endif
-#else
+#  endif
+# else
       arg = buf;
-#endif
+# endif
       break;
 
     case IPC_INFO:
@@ -141,21 +149,25 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf)
       case IPC_STAT:
       case SHM_STAT:
       case SHM_STAT_ANY:
-#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
+# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
         arg->shm_perm.mode >>= 16;
-#else
+# else
       /* Old Linux kernel versions might not clear the mode padding.  */
       if (sizeof ((struct shmid_ds){0}.shm_perm.mode)
          != sizeof (__kernel_mode_t))
        arg->shm_perm.mode &= 0xFFFF;
-#endif
+# endif
 
-#if __IPC_TIME64
+# if __IPC_TIME64
       kshmid64_to_shmid64 (arg, buf);
-#endif
+# endif
     }
 
   return ret;
+
+#else /* !IPC_CTL_NEED_TRANSLATION */
+  return shmctl_syscall (shmid, cmd, buf);
+#endif
 }
 #if __TIMESIZE != 64
 libc_hidden_def (__shmctl64)