ACPI: APEI: Fix AER info corruption when error status data has multiple sections

ghes_handle_aer() passes AER data to the PCI core for logging and
recovery by calling aer_recover_queue() with a pointer to struct
aer_capability_regs.

The problem was that aer_recover_queue() queues the pointer directly
without copying the aer_capability_regs data.  The pointer was to
the ghes->estatus buffer, which could be reused before
aer_recover_work_func() reads the data.

To avoid this problem, allocate a new aer_capability_regs structure
from the ghes_estatus_pool, copy the AER data from the ghes->estatus
buffer into it, pass a pointer to the new struct to
aer_recover_queue(), and free it after aer_recover_work_func() has
processed it.

Reported-by: Bjorn Helgaas <helgaas@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Shiju Jose 2023-09-21 02:03:36 +08:00 committed by Rafael J. Wysocki
parent ce9ecca023
commit e2abc47a5a
3 changed files with 36 additions and 1 deletions

View File

@ -209,6 +209,20 @@ int ghes_estatus_pool_init(unsigned int num_ghes)
return -ENOMEM;
}
/**
* ghes_estatus_pool_region_free - free previously allocated memory
* from the ghes_estatus_pool.
* @addr: address of memory to free.
* @size: size of memory to free.
*
* Returns none.
*/
void ghes_estatus_pool_region_free(unsigned long addr, u32 size)
{
gen_pool_free(ghes_estatus_pool, addr, size);
}
EXPORT_SYMBOL_GPL(ghes_estatus_pool_region_free);
static int map_gen_v2(struct ghes *ghes)
{
return apei_map_generic_address(&ghes->generic_v2->read_ack_register);
@ -564,6 +578,7 @@ static void ghes_handle_aer(struct acpi_hest_generic_data *gdata)
pcie_err->validation_bits & CPER_PCIE_VALID_AER_INFO) {
unsigned int devfn;
int aer_severity;
u8 *aer_info;
devfn = PCI_DEVFN(pcie_err->device_id.device,
pcie_err->device_id.function);
@ -577,11 +592,17 @@ static void ghes_handle_aer(struct acpi_hest_generic_data *gdata)
if (gdata->flags & CPER_SEC_RESET)
aer_severity = AER_FATAL;
aer_info = (void *)gen_pool_alloc(ghes_estatus_pool,
sizeof(struct aer_capability_regs));
if (!aer_info)
return;
memcpy(aer_info, pcie_err->aer_info, sizeof(struct aer_capability_regs));
aer_recover_queue(pcie_err->device_id.segment,
pcie_err->device_id.bus,
devfn, aer_severity,
(struct aer_capability_regs *)
pcie_err->aer_info);
aer_info);
}
#endif
}

View File

@ -29,6 +29,7 @@
#include <linux/kfifo.h>
#include <linux/slab.h>
#include <acpi/apei.h>
#include <acpi/ghes.h>
#include <ras/ras_event.h>
#include "../pci.h"
@ -996,6 +997,15 @@ static void aer_recover_work_func(struct work_struct *work)
continue;
}
cper_print_aer(pdev, entry.severity, entry.regs);
/*
* Memory for aer_capability_regs(entry.regs) is being allocated from the
* ghes_estatus_pool to protect it from overwriting when multiple sections
* are present in the error status. Thus free the same after processing
* the data.
*/
ghes_estatus_pool_region_free((unsigned long)entry.regs,
sizeof(struct aer_capability_regs));
if (entry.severity == AER_NONFATAL)
pcie_do_recovery(pdev, pci_channel_io_normal,
aer_root_reset);

View File

@ -73,8 +73,12 @@ int ghes_register_vendor_record_notifier(struct notifier_block *nb);
void ghes_unregister_vendor_record_notifier(struct notifier_block *nb);
struct list_head *ghes_get_devices(void);
void ghes_estatus_pool_region_free(unsigned long addr, u32 size);
#else
static inline struct list_head *ghes_get_devices(void) { return NULL; }
static inline void ghes_estatus_pool_region_free(unsigned long addr, u32 size) { return; }
#endif
int ghes_estatus_pool_init(unsigned int num_ghes);