Malloc the superblock buffer to make sure that it is properly aligned.

On i386, clang puts the char array at an odd address in .bss.
ok deraadt@

diff --git a/usr.sbin/installboot/i386_installboot.c b/usr.sbin/installboot/i386_installboot.c
index e428d4d..10acf8b 100644 (file)
--- a/usr.sbin/installboot/i386_installboot.c
+++ b/usr.sbin/installboot/i386_installboot.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: i386_installboot.c,v 1.29 2016/05/31 18:35:58 kettenis Exp $  */
+/*     $OpenBSD: i386_installboot.c,v 1.30 2017/06/04 13:57:29 naddy Exp $     */
 /*     $NetBSD: installboot.c,v 1.5 1995/11/17 23:23:50 gwr Exp $ */
 
 /*
@@ -649,8 +649,6 @@ devread(int fd, void *buf, daddr_t blk, size_t size, char *msg)
                err(1, "%s: devread: pread", msg);
 }
 
-static char sblock[SBSIZE];
-
 /*
  * Read information about /boot's inode, then put this and filesystem
  * parameters from the superblock into pbr_symbols.
@@ -663,7 +661,7 @@ getbootparams(char *boot, int devfd, struct disklabel *dl)
        struct statfs   fssb;
        struct partition *pp;
        struct fs       *fs;
-       char            *buf;
+       char            *sblock, *buf;
        u_int           blk, *ap;
        struct ufs1_dinode *ip;
        int             ndb;
@@ -727,6 +725,9 @@ getbootparams(char *boot, int devfd, struct disklabel *dl)
        close(fd);
 
        /* Read superblock. */
+       if ((sblock = malloc(SBSIZE)) == NULL)
+               err(1, NULL);
+
        devread(devfd, sblock, DL_SECTOBLK(dl, pp->p_offset) + SBLOCK,
            SBSIZE, "superblock");
        fs = (struct fs *)sblock;
@@ -794,6 +795,7 @@ getbootparams(char *boot, int devfd, struct disklabel *dl)
                    (unsigned int)((((char *)ap) - buf) + INODEOFF));
        }
 
+       free (sblock);
        free (buf);
 
        return 0;