[PATCH AUTOSEL 6.0 21/34] ACPI: APEI: Fix integer overflow in ghes_estatus_pool_init()

Sasha Levin
2022-11-01T11:30:05Z

From: Ashish Kalra <ashish.kalra@amd.com>

[ Upstream commit 43d2748394c3feb86c0c771466f5847e274fc043 ]

Change num_ghes from int to unsigned int, preventing an overflow
and causing subsequent vmalloc() to fail.

The overflow happens in ghes_estatus_pool_init() when calculating
len during execution of the statement below as both multiplication
operands here are signed int:

len += (num_ghes * GHES_ESOURCE_PREALLOC_MAX_SIZE);

The following call trace is observed because of this bug:

[ 9.317108] swapper/0: vmalloc error: size 18446744071562596352, exceeds total pages, mode:0xcc0(GFP_KERNEL), nodemask=(null),cpuset=/,mems_allowed=0-1
[ 9.317131] Call Trace:
[ 9.317134] <TASK>
[ 9.317137] dump_stack_lvl+0x49/0x5f
[ 9.317145] dump_stack+0x10/0x12
[ 9.317146] warn_alloc.cold+0x7b/0xdf
[ 9.317150] ? __device_attach+0x16a/0x1b0
[ 9.317155] __vmalloc_node_range+0x702/0x740
[ 9.317160] ? device_add+0x17f/0x920
[ 9.317164] ? dev_set_name+0x53/0x70
[ 9.317166] ? platform_device_add+0xf9/0x240
[ 9.317168] __vmalloc_node+0x49/0x50
[ 9.317170] ? ghes_estatus_pool_init+0x43/0xa0
[ 9.317176] vmalloc+0x21/0x30
[ 9.317177] ghes_estatus_pool_init+0x43/0xa0
[ 9.317179] acpi_hest_init+0x129/0x19c
[ 9.317185] acpi_init+0x434/0x4a4
[ 9.317188] ? acpi_sleep_proc_init+0x2a/0x2a
[ 9.317190] do_one_initcall+0x48/0x200
[ 9.317195] kernel_init_freeable+0x221/0x284
[ 9.317200] ? rest_init+0xe0/0xe0
[ 9.317204] kernel_init+0x1a/0x130
[ 9.317205] ret_from_fork+0x22/0x30
[ 9.317208] </TASK>

Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/acpi/apei/ghes.c | 2 +-
include/acpi/ghes.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 80ad530583c9..9952f3a792ba 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -163,7 +163,7 @@ static void ghes_unmap(void __iomem *vaddr, enum fixed_addresses fixmap_idx)
clear_fixmap(fixmap_idx);
}

-int ghes_estatus_pool_init(int num_ghes)
+int ghes_estatus_pool_init(unsigned int num_ghes)
{
unsigned long addr, len;
int rc;
diff --git a/include/acpi/ghes.h b/include/acpi/ghes.h
index 34fb3431a8f3..292a5c40bd0c 100644
--- a/include/acpi/ghes.h
+++ b/include/acpi/ghes.h
@@ -71,7 +71,7 @@ int ghes_register_vendor_record_notifier(struct notifier_block *nb);
void ghes_unregister_vendor_record_notifier(struct notifier_block *nb);
#endif

-int ghes_estatus_pool_init(int num_ghes);
+int ghes_estatus_pool_init(unsigned int num_ghes);

/* From drivers/edac/ghes_edac.c */

--
2.35.1