kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

dmi_scan: refactor dmi_scan_machine(), {smbios,dmi}_present()

Browse source 
Move the calls to memcpy_fromio() up into the loop in
dmi_scan_machine(), and move the signature checks back down into
dmi_decode().  We need to check at 16-byte intervals but keep a 32-byte
buffer for an SMBIOS entry, so shift the buffer after each iteration.

Merge smbios_present() into dmi_present(), so we look for an SMBIOS
signature at the beginning of the given buffer and then for a DMI
signature at an offset of 16 bytes.

[artem.savkov@gmail.com: use proper buf type in dmi_present()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Reported-by: Tim McGrath <tmhikaru@gmail.com>
Tested-by: Tim Mcgrath <tmhikaru@gmail.com>
Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Artem Savkov <artem.savkov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ben Hutchings 2013-04-30 15:27:46 -07:00 committed by Linus Torvalds
parent c1d025e22e
commit 79bae42d51
1 changed files with 37 additions and 43 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

80
drivers/firmware/dmi_scan.c
View file

@ -419,22 +419,45 @@ static void __init dmi_format_ids(char *buf, size_t len)
dmi_get_system_info(DMI_BIOS_DATE));
}
static int __init dmi_present(const char __iomem *p)
static int __init dmi_present(const u8 *buf)
{
u8 buf[15];
int smbios_ver;
memcpy_fromio(buf, p, 15);
if (dmi_checksum(buf, 15)) {
if (memcmp(buf, "_SM_", 4) == 0 &&
buf[5] < 32 && dmi_checksum(buf, buf[5])) {
smbios_ver = (buf[6] << 8) + buf[7];
/* Some BIOS report weird SMBIOS version, fix that up */
switch (smbios_ver) {
case 0x021F:
case 0x0221:
pr_debug("SMBIOS version fixup(2.%d->2.%d)\n",
smbios_ver & 0xFF, 3);
smbios_ver = 0x0203;
break;
case 0x0233:
pr_debug("SMBIOS version fixup(2.%d->2.%d)\n", 51, 6);
smbios_ver = 0x0206;
break;
}
} else {
smbios_ver = 0;
}
buf += 16;
if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
dmi_num = (buf[13] << 8) | buf[12];
dmi_len = (buf[7] << 8) | buf[6];
dmi_base = (buf[11] << 24) | (buf[10] << 16) |
(buf[9] << 8) | buf[8];
if (dmi_walk_early(dmi_decode) == 0) {
if (dmi_ver)
if (smbios_ver) {
dmi_ver = smbios_ver;
pr_info("SMBIOS %d.%d present.\n",
dmi_ver >> 8, dmi_ver & 0xFF);
else {
} else {
dmi_ver = (buf[14] & 0xF0) << 4 |
(buf[14] & 0x0F);
pr_info("Legacy DMI %d.%d present.\n",
@ -445,40 +468,14 @@ static int __init dmi_present(const char __iomem *p)
return 0;
}
}
dmi_ver = 0;
return 1;
}
static int __init smbios_present(const char __iomem *p)
{
u8 buf[32];
memcpy_fromio(buf, p, 32);
if ((buf[5] < 32) && dmi_checksum(buf, buf[5])) {
dmi_ver = (buf[6] << 8) + buf[7];
/* Some BIOS report weird SMBIOS version, fix that up */
switch (dmi_ver) {
case 0x021F:
case 0x0221:
pr_debug("SMBIOS version fixup(2.%d->2.%d)\n",
dmi_ver & 0xFF, 3);
dmi_ver = 0x0203;
break;
case 0x0233:
pr_debug("SMBIOS version fixup(2.%d->2.%d)\n", 51, 6);
dmi_ver = 0x0206;
break;
}
return memcmp(p + 16, "_DMI_", 5) || dmi_present(p + 16);
}
return 1;
}
void __init dmi_scan_machine(void)
{
char __iomem *p, *q;
int rc;
char buf[32];
if (efi_enabled(EFI_CONFIG_TABLES)) {
if (efi.smbios == EFI_INVALID_TABLE_ADDR)
@ -491,10 +488,10 @@ void __init dmi_scan_machine(void)
p = dmi_ioremap(efi.smbios, 32);
if (p == NULL)
goto error;
rc = smbios_present(p);
memcpy_fromio(buf, p, 32);
dmi_iounmap(p, 32);
if (!rc) {
if (!dmi_present(buf)) {
dmi_available = 1;
goto out;
}
@ -509,18 +506,15 @@ void __init dmi_scan_machine(void)
if (p == NULL)
goto error;
memset(buf, 0, 16);
for (q = p; q < p + 0x10000; q += 16) {
if (memcmp(q, "_SM_", 4) == 0 && q - p <= 0xFFE0)
rc = smbios_present(q);
else if (memcmp(q, "_DMI_", 5) == 0)
rc = dmi_present(q);
else
continue;
if (!rc) {
memcpy_fromio(buf + 16, q, 16);
if (!dmi_present(buf)) {
dmi_available = 1;
dmi_iounmap(p, 0x10000);
goto out;
}
memcpy(buf, buf + 16, 16);
}
dmi_iounmap(p, 0x10000);
}