[syslinux:firmware] derivative_info: be sure not to dereference pointers
syslinux-bot for Matt Fleming
matt.fleming at intel.com
Mon Jul 22 06:33:06 PDT 2013
Commit-ID: c6b80d76a6e1f76cdb5f1deaf298514843d0116a
Gitweb: http://www.syslinux.org/commit/c6b80d76a6e1f76cdb5f1deaf298514843d0116a
Author: Matt Fleming <matt.fleming at intel.com>
AuthorDate: Mon, 22 Jul 2013 13:41:00 +0100
Committer: Matt Fleming <matt.fleming at intel.com>
CommitDate: Mon, 22 Jul 2013 14:30:32 +0100
derivative_info: be sure not to dereference pointers
All the BIOS get_derivative_info() implementations are incorrect. They
all dereference pointers to various deriviative-specific data objects
instead of using the address of the objects.
This broke chain loading on SYSLINUX because the ->partoffset field
contained the dereferenced value of 'Hidden' rather than the address.
Signed-off-by: Matt Fleming <matt.fleming at intel.com>
---
core/isolinux-c.c | 10 +++++-----
core/ldlinux-c.c | 12 ++++++------
core/pxelinux-c.c | 8 ++++----
3 files changed, 15 insertions(+), 15 deletions(-)
diff --git a/core/isolinux-c.c b/core/isolinux-c.c
index 8574eac..b0173e0 100644
--- a/core/isolinux-c.c
+++ b/core/isolinux-c.c
@@ -2,8 +2,8 @@
#include <com32.h>
#include <fs.h>
-extern far_ptr_t OrigESDI;
-extern const uint64_t *Hidden;
+extern uint32_t OrigESDI;
+extern const uint64_t Hidden;
extern uint16_t BIOSType;
extern uint16_t bios_cdrom;
extern uint8_t DriveNumber;
@@ -16,7 +16,7 @@ __export void get_derivative_info(union syslinux_derivative_info *di)
di->iso.drive_number = DriveNumber;
di->iso.cd_mode = ((BIOSType - bios_cdrom) >> 2);
- di->iso.spec_packet = spec_packet;
- di->iso.esdi_ptr = GET_PTR(OrigESDI);
- di->iso.partoffset = Hidden;
+ di->iso.spec_packet = &spec_packet;
+ di->iso.esdi_ptr = &OrigESDI;
+ di->iso.partoffset = &Hidden;
}
diff --git a/core/ldlinux-c.c b/core/ldlinux-c.c
index 0b9aa76..1d01d9a 100644
--- a/core/ldlinux-c.c
+++ b/core/ldlinux-c.c
@@ -3,9 +3,9 @@
#include <fs.h>
extern uint8_t DriveNumber;
-extern far_ptr_t PartInfo;
-extern far_ptr_t OrigESDI;
-extern const uint64_t *Hidden;
+extern void *PartInfo;
+extern uint32_t OrigESDI;
+extern const uint64_t Hidden;
__export void get_derivative_info(union syslinux_derivative_info *di)
{
@@ -13,7 +13,7 @@ __export void get_derivative_info(union syslinux_derivative_info *di)
di->disk.sector_shift = SectorShift;
di->disk.drive_number = DriveNumber;
- di->disk.ptab_ptr = GET_PTR(PartInfo);
- di->disk.esdi_ptr = GET_PTR(OrigESDI);
- di->disk.partoffset = Hidden;
+ di->disk.ptab_ptr = &PartInfo;
+ di->disk.esdi_ptr = &OrigESDI;
+ di->disk.partoffset = &Hidden;
}
diff --git a/core/pxelinux-c.c b/core/pxelinux-c.c
index 69c9aac..3683189 100644
--- a/core/pxelinux-c.c
+++ b/core/pxelinux-c.c
@@ -1,8 +1,8 @@
#include <syslinux/config.h>
#include <com32.h>
-extern far_ptr_t StrucPtr;
-extern far_ptr_t InitStack;
+extern void *StrucPtr;
+extern void *InitStack;
/*
* IP information. Note that the field are in the same order as the
@@ -15,8 +15,8 @@ __export void get_derivative_info(union syslinux_derivative_info *di)
{
di->pxe.filesystem = SYSLINUX_FS_PXELINUX;
di->pxe.apiver = APIVer;
- di->pxe.pxenvptr = GET_PTR(StrucPtr);
- di->pxe.stack = GET_PTR(InitStack);
+ di->pxe.pxenvptr = &StrucPtr;
+ di->pxe.stack = &InitStack;
di->pxe.ipinfo = &IPInfo;
di->pxe.myip = IPInfo.myip;
}
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