diff options
| author | Mike Smith <msmith@FreeBSD.org> | 1999-08-24 16:42:08 +0000 |
|---|---|---|
| committer | Mike Smith <msmith@FreeBSD.org> | 1999-08-24 16:42:08 +0000 |
| commit | e6a80efcddded72bb6f6accd1dee9e4f5b6563b9 (patch) | |
| tree | 281c9ba49ee8600b0b847debe7cb8ce3c57f67ee /sys | |
| parent | b01aa9b2b2b61ecdafda0288da28e0c2d2f0c127 (diff) | |
Notes
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/amd64/amd64/bios.c | 13 | ||||
| -rw-r--r-- | sys/i386/i386/bios.c | 13 |
2 files changed, 22 insertions, 4 deletions
diff --git a/sys/amd64/amd64/bios.c b/sys/amd64/amd64/bios.c index 980c0b52a4d28..cc8e30bf36ba4 100644 --- a/sys/amd64/amd64/bios.c +++ b/sys/amd64/amd64/bios.c @@ -24,7 +24,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $Id: bios.c,v 1.17 1999/08/18 02:19:52 msmith Exp $ + * $Id: bios.c,v 1.18 1999/08/20 21:08:41 msmith Exp $ */ /* @@ -315,7 +315,16 @@ bios16(struct bios_args *args, char *fmt, ...) arg_start = 0xffffffff; arg_end = 0; - stack = (caddr_t)PAGE_SIZE; + /* + * Some BIOS entrypoints attempt to copy the largest-case + * argument frame (in order to generalise handling for + * different entry types). If our argument frame is + * smaller than this, the BIOS will reach off the top of + * our constructed stack segment. Pad the top of the stack + * with some garbage to avoid this. + */ + stack = (caddr_t)PAGE_SIZE - 32; + va_start(ap, fmt); for (p = fmt; p && *p; p++) { switch (*p) { diff --git a/sys/i386/i386/bios.c b/sys/i386/i386/bios.c index 980c0b52a4d28..cc8e30bf36ba4 100644 --- a/sys/i386/i386/bios.c +++ b/sys/i386/i386/bios.c @@ -24,7 +24,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $Id: bios.c,v 1.17 1999/08/18 02:19:52 msmith Exp $ + * $Id: bios.c,v 1.18 1999/08/20 21:08:41 msmith Exp $ */ /* @@ -315,7 +315,16 @@ bios16(struct bios_args *args, char *fmt, ...) arg_start = 0xffffffff; arg_end = 0; - stack = (caddr_t)PAGE_SIZE; + /* + * Some BIOS entrypoints attempt to copy the largest-case + * argument frame (in order to generalise handling for + * different entry types). If our argument frame is + * smaller than this, the BIOS will reach off the top of + * our constructed stack segment. Pad the top of the stack + * with some garbage to avoid this. + */ + stack = (caddr_t)PAGE_SIZE - 32; + va_start(ap, fmt); for (p = fmt; p && *p; p++) { switch (*p) { |