From 996649b073c98b4f13d2908cf887f4bd52d2ce5f Mon Sep 17 00:00:00 2001 From: Vladimir 'phcoder' Serbinenko Date: Wed, 3 Feb 2010 00:43:55 +0100 Subject: [PATCH] 2010-02-03 Vladimir Serbinenko * disk/i386/pc/biosdisk.c (grub_biosdisk_read): Handle non-2048 aligned CDROM reads. (grub_biosdisk_write): Refuse to write to CDROM. --- ChangeLog | 6 ++++++ disk/i386/pc/biosdisk.c | 14 +++++++++++++- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index 4598e1b74..83d0c58a8 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2010-02-03 Vladimir Serbinenko + + * disk/i386/pc/biosdisk.c (grub_biosdisk_read): Handle non-2048 aligned + CDROM reads. + (grub_biosdisk_write): Refuse to write to CDROM. + 2010-01-31 Vladimir Serbinenko * disk/ieee1275/ofdisk.c (grub_ofdisk_iterate): Fix off-by-one error. diff --git a/disk/i386/pc/biosdisk.c b/disk/i386/pc/biosdisk.c index 682474b1a..94d0e3708 100644 --- a/disk/i386/pc/biosdisk.c +++ b/disk/i386/pc/biosdisk.c @@ -307,8 +307,17 @@ grub_biosdisk_read (grub_disk_t disk, grub_disk_addr_t sector, while (size) { grub_size_t len; + grub_size_t cdoff = 0; len = get_safe_sectors (sector, data->sectors); + + if (data->flags & GRUB_BIOSDISK_FLAG_CDROM) + { + cdoff = (sector & 3) << GRUB_DISK_SECTOR_BITS; + len = ALIGN_UP (sector + len, 4) - (sector & ~3); + sector &= ~3; + } + if (len > size) len = size; @@ -316,7 +325,7 @@ grub_biosdisk_read (grub_disk_t disk, grub_disk_addr_t sector, GRUB_MEMORY_MACHINE_SCRATCH_SEG)) return grub_errno; - grub_memcpy (buf, (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR, + grub_memcpy (buf, (void *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + cdoff), len << GRUB_DISK_SECTOR_BITS); buf += len << GRUB_DISK_SECTOR_BITS; sector += len; @@ -332,6 +341,9 @@ grub_biosdisk_write (grub_disk_t disk, grub_disk_addr_t sector, { struct grub_biosdisk_data *data = disk->data; + if (data->flags & GRUB_BIOSDISK_FLAG_CDROM) + return grub_error (GRUB_ERR_IO, "can't write to CDROM"); + while (size) { grub_size_t len; -- 2.39.5