Syslinux - Jan 2013 - chain.c32 bug

i`ve found a bug in chain.c32 in v4.06. When i use isolinux it does not run
windows7 installation, chainloading bootmgr.
the error is: Can't find myself on the drive I booted from.
chain.c32 from syslinux 3.xx works like a charm!

chain.c32 from syslinux 5 shous tat this is not a com32 app

> i`ve found a bug in chain.c32 in v4.06. When i use isolinux it does not run
> windows7 installation, chainloading bootmgr.
> the error is: Can't find myself on the drive I booted from.
> chain.c32 from syslinux 3.xx works like a charm!
> 
> chain.c32 from syslinux 5 shous tat this is not a com32 app
Q1: When you tried those different versions of chain.c32, have you 
also used the corresponding version of ISOLINUX? Or you only changed 
chain.c32 versions?

Q2: When testing chain.c32 from Syslinux 5.00 and booting with 
isolinux.bin from the same version, have you also used (at least) 
ldlinux.c32, libutil_com.c32 and libcom32.c32 (or ldlinux.c32 + all 
lib*.c32 files)?

Regards,
Ady.

On 2013-01-07 09:19, c c wrote:
> i`ve found a bug in chain.c32 in v4.06. When i use isolinux it does not run
> windows7 installation, chainloading bootmgr.
> the error is: Can't find myself on the drive I booted from.
> chain.c32 from syslinux 3.xx works like a charm!
> 
Did you use 'fs' as partition specification ? What were the options used
?

If you can compile, try this small patch (against 4.06), this will cover
whole disk as a candidate as well when fs_lba is considered:

diff --git a/com32/chain/chain.c b/com32/chain/chain.c
index 30153c4..b1a9ed8 100644
--- a/com32/chain/chain.c
+++ b/com32/chain/chain.c
@@ -353,10 +353,10 @@ int find_dp(struct part_iter **_iter)
 
 	/* 'fs' => we should lookup the syslinux partition number and use
it */
 	if (!strcmp(opt.drivename, "fs")) {
-	    while (!pi_next(&iter)) {
+	    do {
 		if (iter->start_lba == fs_lba)
 		    break;
-	    }
+	    } while (!pi_next(&iter));
 	    /* broken part structure or other problems */
 	    if (iter->status) {
 		error("Can't find myself on the drive I booted from.\n");