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-rw-r--r--hw/ide.c21
1 files changed, 15 insertions, 6 deletions
diff --git a/hw/ide.c b/hw/ide.c
index bc7ebd3205..e922e7ba7c 100644
--- a/hw/ide.c
+++ b/hw/ide.c
@@ -1826,11 +1826,11 @@ struct partition {
uint32_t nr_sects; /* nr of sectors in partition */
} __attribute__((packed));
-/* try to guess the IDE geometry from the MSDOS partition table */
+/* try to guess the IDE physical geometry from the MSDOS partition table */
static void ide_guess_geometry(IDEState *s)
{
uint8_t buf[512];
- int ret, i;
+ int ret, i, heads, sectors, cylinders;
struct partition *p;
uint32_t nr_sects;
@@ -1848,9 +1848,18 @@ static void ide_guess_geometry(IDEState *s)
if (nr_sects && p->end_head) {
/* We make the assumption that the partition terminates on
a cylinder boundary */
- s->heads = p->end_head + 1;
- s->sectors = p->end_sector & 63;
- s->cylinders = s->nb_sectors / (s->heads * s->sectors);
+ heads = p->end_head + 1;
+ if (heads < 1 || heads > 16)
+ continue;
+ sectors = p->end_sector & 63;
+ if (sectors == 0)
+ continue;
+ cylinders = s->nb_sectors / (heads * sectors);
+ if (cylinders < 1 || cylinders > 16383)
+ continue;
+ s->heads = heads;
+ s->sectors = sectors;
+ s->cylinders = cylinders;
#if 0
printf("guessed partition: CHS=%d %d %d\n",
s->cylinders, s->heads, s->sectors);
@@ -1885,7 +1894,7 @@ static void ide_init2(IDEState *ide_state, int irq,
} else {
ide_guess_geometry(s);
if (s->cylinders == 0) {
- /* if no geometry, use a LBA compatible one */
+ /* if no geometry, use a standard physical disk geometry */
cylinders = nb_sectors / (16 * 63);
if (cylinders > 16383)
cylinders = 16383;