Avoid relying on implementation-specific behavior when detecting

whether the timestamp or file size overflowed.  If time_t and
off_t are not either 32-bit or 64-bit scp will exit with an error.
OK djm@

diff --git a/usr.bin/ssh/scp.c b/usr.bin/ssh/scp.c
index dcf6837..f61b3dd 100644 (file)
--- a/usr.bin/ssh/scp.c
+++ b/usr.bin/ssh/scp.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: scp.c,v 1.188 2017/04/27 11:53:12 millert Exp $ */
+/* $OpenBSD: scp.c,v 1.189 2017/04/28 03:21:12 millert Exp $ */
 /*
  * scp - secure remote copy.  This is basically patched BSD rcp which
  * uses ssh to do the data transfer (instead of using rcmd).
@@ -86,6 +86,7 @@
 #include <pwd.h>
 #include <signal.h>
 #include <stdarg.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -894,6 +895,11 @@ rsource(char *name, struct stat *statp)
        (void) response();
 }
 
+#define TYPE_OVERFLOW(type, val) \
+       ((sizeof(type) == 4 && (val) > INT32_MAX) || \
+        (sizeof(type) == 8 && (val) > INT64_MAX) || \
+        (sizeof(type) != 4 && sizeof(type) != 8))
+
 void
 sink(int argc, char **argv)
 {
@@ -917,6 +923,9 @@ sink(int argc, char **argv)
 #define        mtime   tv[1]
 #define        SCREWUP(str)    { why = str; goto screwup; }
 
+       if (TYPE_OVERFLOW(time_t, 0) || TYPE_OVERFLOW(off_t, 0))
+               SCREWUP("Unexpected off_t/time_t size");
+
        setimes = targisdir = 0;
        mask = umask(0);
        if (!pflag)
@@ -975,8 +984,7 @@ sink(int argc, char **argv)
                        ull = strtoull(cp, &cp, 10);
                        if (!cp || *cp++ != ' ')
                                SCREWUP("mtime.sec not delimited");
-                       if ((time_t)ull < 0 ||
-                           (unsigned long long)(time_t)ull != ull)
+                       if (TYPE_OVERFLOW(time_t, ull))
                                setimes = 0;    /* out of range */
                        mtime.tv_sec = ull;
                        mtime.tv_usec = strtol(cp, &cp, 10);
@@ -988,8 +996,7 @@ sink(int argc, char **argv)
                        ull = strtoull(cp, &cp, 10);
                        if (!cp || *cp++ != ' ')
                                SCREWUP("atime.sec not delimited");
-                       if ((time_t)ull < 0 ||
-                           (unsigned long long)(time_t)ull != ull)
+                       if (TYPE_OVERFLOW(time_t, ull))
                                setimes = 0;    /* out of range */
                        atime.tv_sec = ull;
                        atime.tv_usec = strtol(cp, &cp, 10);
@@ -1027,7 +1034,7 @@ sink(int argc, char **argv)
                ull = strtoull(cp, &cp, 10);
                if (!cp || *cp++ != ' ')
                        SCREWUP("size not delimited");
-               if ((off_t)ull < 0 || (unsigned long long)(off_t)ull != ull)
+               if (TYPE_OVERFLOW(off_t, ull))
                        SCREWUP("size out of range");
                size = (off_t)ull;