[PATCH AUTOSEL 6.0 09/18] ACPI: tables: FPDT: Don't call acpi_os_map_memory() on invalid phys address

From: Sasha Levin
Date: Sun Oct 09 2022 - 16:52:34 EST


From: Hans de Goede <hdegoede@xxxxxxxxxx>

[ Upstream commit 211391bf04b3c74e250c566eeff9cf808156c693 ]

On a Packard Bell Dot SC (Intel Atom N2600 model) there is a FPDT table
which contains invalid physical addresses, with high bits set which fall
outside the range of the CPU-s supported physical address range.

Calling acpi_os_map_memory() on such an invalid phys address leads to
the below WARN_ON in ioremap triggering resulting in an oops/stacktrace.

Add code to verify the physical address before calling acpi_os_map_memory()
to fix / avoid the oops.

[ 1.226900] ioremap: invalid physical address 3001000000000000
[ 1.226949] ------------[ cut here ]------------
[ 1.226962] WARNING: CPU: 1 PID: 1 at arch/x86/mm/ioremap.c:200 __ioremap_caller.cold+0x43/0x5f
[ 1.226996] Modules linked in:
[ 1.227016] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc3+ #490
[ 1.227029] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/23/2013
[ 1.227038] RIP: 0010:__ioremap_caller.cold+0x43/0x5f
[ 1.227054] Code: 96 00 00 e9 f8 af 24 ff 89 c6 48 c7 c7 d8 0c 84 99 e8 6a 96 00 00 e9 76 af 24 ff 48 89 fe 48 c7 c7 a8 0c 84 99 e8 56 96 00 00 <0f> 0b e9 60 af 24 ff 48 8b 34 24 48 c7 c7 40 0d 84 99 e8 3f 96 00
[ 1.227067] RSP: 0000:ffffb18c40033d60 EFLAGS: 00010286
[ 1.227084] RAX: 0000000000000032 RBX: 3001000000000000 RCX: 0000000000000000
[ 1.227095] RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00000000ffffffff
[ 1.227105] RBP: 3001000000000000 R08: 0000000000000000 R09: ffffb18c40033c18
[ 1.227115] R10: 0000000000000003 R11: ffffffff99d62fe8 R12: 0000000000000008
[ 1.227124] R13: 0003001000000000 R14: 0000000000001000 R15: 3001000000000000
[ 1.227135] FS: 0000000000000000(0000) GS:ffff913a3c080000(0000) knlGS:0000000000000000
[ 1.227146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.227156] CR2: 0000000000000000 CR3: 0000000018c26000 CR4: 00000000000006e0
[ 1.227167] Call Trace:
[ 1.227176] <TASK>
[ 1.227185] ? acpi_os_map_iomem+0x1c9/0x1e0
[ 1.227215] ? kmem_cache_alloc_trace+0x187/0x370
[ 1.227254] acpi_os_map_iomem+0x1c9/0x1e0
[ 1.227288] acpi_init_fpdt+0xa8/0x253
[ 1.227308] ? acpi_debugfs_init+0x1f/0x1f
[ 1.227339] do_one_initcall+0x5a/0x300
[ 1.227406] ? rcu_read_lock_sched_held+0x3f/0x80
[ 1.227442] kernel_init_freeable+0x28b/0x2cc
[ 1.227512] ? rest_init+0x170/0x170
[ 1.227538] kernel_init+0x16/0x140
[ 1.227552] ret_from_fork+0x1f/0x30
[ 1.227639] </TASK>
[ 1.227647] irq event stamp: 186819
[ 1.227656] hardirqs last enabled at (186825): [<ffffffff98184a6e>] __up_console_sem+0x5e/0x70
[ 1.227672] hardirqs last disabled at (186830): [<ffffffff98184a53>] __up_console_sem+0x43/0x70
[ 1.227686] softirqs last enabled at (186576): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160
[ 1.227701] softirqs last disabled at (186569): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160
[ 1.227715] ---[ end trace 0000000000000000 ]---

Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/acpi/acpi_fpdt.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/drivers/acpi/acpi_fpdt.c b/drivers/acpi/acpi_fpdt.c
index 6922a44b3ce7..a2056c4c8cb7 100644
--- a/drivers/acpi/acpi_fpdt.c
+++ b/drivers/acpi/acpi_fpdt.c
@@ -143,6 +143,23 @@ static const struct attribute_group boot_attr_group = {

static struct kobject *fpdt_kobj;

+#if defined CONFIG_X86 && defined CONFIG_PHYS_ADDR_T_64BIT
+#include <linux/processor.h>
+static bool fpdt_address_valid(u64 address)
+{
+ /*
+ * On some systems the table contains invalid addresses
+ * with unsuppored high address bits set, check for this.
+ */
+ return !(address >> boot_cpu_data.x86_phys_bits);
+}
+#else
+static bool fpdt_address_valid(u64 address)
+{
+ return true;
+}
+#endif
+
static int fpdt_process_subtable(u64 address, u32 subtable_type)
{
struct fpdt_subtable_header *subtable_header;
@@ -151,6 +168,11 @@ static int fpdt_process_subtable(u64 address, u32 subtable_type)
u32 length, offset;
int result;

+ if (!fpdt_address_valid(address)) {
+ pr_info(FW_BUG "invalid physical address: 0x%llx!\n", address);
+ return -EINVAL;
+ }
+
subtable_header = acpi_os_map_memory(address, sizeof(*subtable_header));
if (!subtable_header)
return -ENOMEM;
--
2.35.1