acpi: fix file size check with -acpitable.

acpi table file can be modified during load so file size check
should be more strict.
pointer calculation should be after qemu_realloc(). not before realloc().

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This commit is contained in:
Isaku Yamahata 2010-07-28 23:08:42 +00:00 committed by Blue Swirl
parent 02a89b2190
commit d729bb9a77

View File

@ -50,6 +50,8 @@ int acpi_table_add(const char *t)
char buf[1024], *p, *f;
struct acpi_table_header acpi_hdr;
unsigned long val;
uint32_t length;
struct acpi_table_header *acpi_hdr_p;
size_t off;
memset(&acpi_hdr, 0, sizeof(acpi_hdr));
@ -108,7 +110,7 @@ int acpi_table_add(const char *t)
buf[0] = '\0';
}
acpi_hdr.length = sizeof(acpi_hdr);
length = sizeof(acpi_hdr);
f = buf;
while (buf[0]) {
@ -120,7 +122,7 @@ int acpi_table_add(const char *t)
fprintf(stderr, "Can't stat file '%s': %s\n", f, strerror(errno));
goto out;
}
acpi_hdr.length += s.st_size;
length += s.st_size;
if (!n)
break;
*n = ':';
@ -131,12 +133,12 @@ int acpi_table_add(const char *t)
acpi_tables_len = sizeof(uint16_t);
acpi_tables = qemu_mallocz(acpi_tables_len);
}
acpi_tables = qemu_realloc(acpi_tables,
acpi_tables_len + sizeof(uint16_t) + length);
p = acpi_tables + acpi_tables_len;
acpi_tables_len += sizeof(uint16_t) + acpi_hdr.length;
acpi_tables = qemu_realloc(acpi_tables, acpi_tables_len);
acpi_tables_len += sizeof(uint16_t) + length;
acpi_hdr.length = cpu_to_le32(acpi_hdr.length);
*(uint16_t*)p = acpi_hdr.length;
*(uint16_t*)p = cpu_to_le32(length);
p += sizeof(uint16_t);
memcpy(p, &acpi_hdr, sizeof(acpi_hdr));
off = sizeof(acpi_hdr);
@ -157,7 +159,9 @@ int acpi_table_add(const char *t)
goto out;
}
do {
/* off < length is necessary because file size can be changed
under our foot */
while(s.st_size && off < length); {
int r;
r = read(fd, p + off, s.st_size);
if (r > 0) {
@ -167,15 +171,21 @@ int acpi_table_add(const char *t)
close(fd);
goto out;
}
} while(s.st_size);
}
close(fd);
if (!n)
break;
f = n + 1;
}
if (off < length) {
/* don't pass random value in process to guest */
memset(p + off, 0, length - off);
}
((struct acpi_table_header*)p)->checksum = acpi_checksum((uint8_t*)p, off);
acpi_hdr_p = (struct acpi_table_header*)p;
acpi_hdr_p->length = cpu_to_le32(length);
acpi_hdr_p->checksum = acpi_checksum((uint8_t*)p, length);
/* increase number of tables */
(*(uint16_t*)acpi_tables) =
cpu_to_le32(le32_to_cpu(*(uint16_t*)acpi_tables) + 1);