From: Prarit Bhargava Date: Wed, 31 May 2017 17:32:00 +0000 (-0400) Subject: acpi/nfit: Fix memory corruption/Unregister mce decoder on failure X-Git-Tag: C0P2-H0.0--20200415~8019 X-Git-Url: https://git.somdevices.com/?a=commitdiff_plain;h=6b50bca7cdb0822628f45bea2bb028630999aa13;p=linux.git acpi/nfit: Fix memory corruption/Unregister mce decoder on failure commit 7e700d2c59e5853c9126642976b4f5768f64c9b3 upstream. nfit_init() calls nfit_mce_register() on module load. When the module load fails the nfit mce decoder is not unregistered. The module's memory is freed leaving the decoder chain referencing junk. This will cause panics as future registrations will reference the free'd memory. Unregister the nfit mce decoder on module init failure. [v2]: register and then unregister mce handler to avoid losing mce events [v3]: also cleanup nfit workqueue Fixes: 6839a6d96f4e ("nfit: do an ARS scrub on hitting a latent media error") Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Vishal Verma Cc: "Lee, Chun-Yi" Cc: Linda Knippers Cc: lszubowi@redhat.com Acked-by: Jeff Moyer Signed-off-by: Prarit Bhargava Reviewed-by: Vishal Verma Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 9ef3941eeff0..f3bc901ac930 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -2945,6 +2945,8 @@ static struct acpi_driver acpi_nfit_driver = { static __init int nfit_init(void) { + int ret; + BUILD_BUG_ON(sizeof(struct acpi_table_nfit) != 40); BUILD_BUG_ON(sizeof(struct acpi_nfit_system_address) != 56); BUILD_BUG_ON(sizeof(struct acpi_nfit_memory_map) != 48); @@ -2972,8 +2974,14 @@ static __init int nfit_init(void) return -ENOMEM; nfit_mce_register(); + ret = acpi_bus_register_driver(&acpi_nfit_driver); + if (ret) { + nfit_mce_unregister(); + destroy_workqueue(nfit_wq); + } + + return ret; - return acpi_bus_register_driver(&acpi_nfit_driver); } static __exit void nfit_exit(void)