Implement the chmod a-x bsd.upgrade trick in the sparc64 ofwboot bootloader.

OK deraadt@ florian@ kn@

diff --git a/sys/arch/sparc64/stand/ofwboot/boot.c b/sys/arch/sparc64/stand/ofwboot/boot.c
index a047610..0fc4fc8 100644 (file)
--- a/sys/arch/sparc64/stand/ofwboot/boot.c
+++ b/sys/arch/sparc64/stand/ofwboot/boot.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: boot.c,v 1.43 2023/06/03 21:37:53 krw Exp $   */
+/*     $OpenBSD: boot.c,v 1.44 2024/03/26 14:46:48 claudio Exp $       */
 /*     $NetBSD: boot.c,v 1.3 2001/05/31 08:55:19 mrg Exp $     */
 /*
  * Copyright (c) 1997, 1999 Eduardo E. Horvath.  All rights reserved.
@@ -212,7 +212,7 @@ chain(u_int64_t pentry, char *args, void *ssym, void *esym)
 }
 
 int
-loadfile(int fd, char *args)
+loadfile(int fd, char *args, int isupgrade)
 {
        union {
                Elf64_Ehdr elf64;
@@ -254,6 +254,16 @@ loadfile(int fd, char *args)
 
        printf(" start=0x%lx\n", (unsigned long)entry);
 
+       /* Prevent re-upgrade: chmod a-x bsd.upgrade */
+       if (isupgrade) {
+               struct stat st;
+
+               if (fstat(fd, &st) == 0) {
+                       st.st_mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
+                       if (fchmod(fd, st.st_mode) == -1)
+                               printf("fchmod a-x %s: failed\n", opened_name);
+               }
+       }
        close(fd);
 
 #ifdef SOFTRAID
@@ -276,6 +286,10 @@ upgrade(void)
 
        if (stat("/bsd.upgrade", &sb) < 0)
                return 0;
+       if ((sb.st_mode & S_IXUSR) == 0) {
+               printf("/bsd.upgrade is not u+x\n");
+               return 0;
+        }
        return 1;
 }
 
@@ -413,6 +427,7 @@ main(void)
 {
        extern char version[];
        int chosen;
+       int isupgrade = 0;
        char bootline[512];             /* Should check size? */
        char *cp;
        int fd;
@@ -461,10 +476,10 @@ main(void)
                just_bootline[0] = bootline;
                just_bootline[1] = 0;
                bootlp = just_bootline;
-       }
-       if (bootlp == kernels && upgrade()) {
+       } else if (upgrade()) {
                just_bootline[0] = "/bsd.upgrade";
                just_bootline[1] = 0;
+               isupgrade = 1;
                bootlp = just_bootline;
                printf("upgrade detected: switching to %s\n", *bootlp);
        }
@@ -514,7 +529,7 @@ main(void)
                if (debug)
                        printf("main: Calling loadfile(fd, %s)\n", opened_name);
 #endif
-               (void)loadfile(fd, opened_name);
+               (void)loadfile(fd, opened_name, isupgrade);
        }
        return 0;
 }

diff --git a/sys/arch/sparc64/stand/ofwboot/vers.c b/sys/arch/sparc64/stand/ofwboot/vers.c
index 078165b..a5f408e 100644 (file)
--- a/sys/arch/sparc64/stand/ofwboot/vers.c
+++ b/sys/arch/sparc64/stand/ofwboot/vers.c
@@ -1 +1 @@
-const char version[] = "1.27";
+const char version[] = "1.28";