From a35302316c1c36e22b60d1644db0340558de695f Mon Sep 17 00:00:00 2001 From: Vegard Nossum Date: Mon, 8 Jun 2020 09:57:51 +0200 Subject: [PATCH] ACPICA: Always create namespace nodes using acpi_ns_create_node() ACPI is allocating an object using kmalloc(), but then frees it using kmem_cache_free(<"Acpi-Namespace" kmem_cache>). This is wrong and can lead to boot failures manifesting like this: hpet0: 3 comparators, 64-bit 100.000000 MHz counter clocksource: Switched to clocksource tsc-early BUG: unable to handle page fault for address: 000000003ffe0018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0+ #211 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 RIP: 0010:kmem_cache_alloc+0x70/0x1d0 Code: 00 00 4c 8b 45 00 65 49 8b 50 08 65 4c 03 05 6f cc e7 7e 4d 8b 20 4d 85 e4 0f 84 3d 01 00 00 8b 45 20 48 8b 7d 00 48 8d 4a 01 <49> 8b 1c 04 4c 89 e0 65 48 0f c7 0f 0f 94 c0 84 c0 74 c5 8b 45 20 RSP: 0000:ffffc90000013df8 EFLAGS: 00010206 RAX: 0000000000000018 RBX: ffffffff81c49200 RCX: 0000000000000002 RDX: 0000000000000001 RSI: 0000000000000dc0 RDI: 000000000002b300 RBP: ffff88803e403d00 R08: ffff88803ec2b300 R09: 0000000000000001 R10: 0000000000000dc0 R11: 0000000000000006 R12: 000000003ffe0000 R13: ffffffff8110a583 R14: 0000000000000dc0 R15: ffffffff81c49a80 FS: 0000000000000000(0000) GS:ffff88803ec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000003ffe0018 CR3: 0000000001c0a001 CR4: 00000000003606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __trace_define_field+0x33/0xa0 event_trace_init+0xeb/0x2b4 tracer_init_tracefs+0x60/0x195 ? register_tracer+0x1e7/0x1e7 do_one_initcall+0x74/0x160 kernel_init_freeable+0x190/0x1f0 ? rest_init+0x9a/0x9a kernel_init+0x5/0xf6 ret_from_fork+0x35/0x40 CR2: 000000003ffe0018 ---[ end trace 707efa023f2ee960 ]--- RIP: 0010:kmem_cache_alloc+0x70/0x1d0 Bisection leads to unrelated changes in slab; Vlastimil Babka suggests an unrelated layout or slab merge change merely exposed the underlying bug. Link: https://lore.kernel.org/lkml/4dc93ff8-f86e-f4c9-ebeb-6d3153a78d03@oracle.com/ Link: https://lore.kernel.org/r/a1461e21-c744-767d-6dfc-6641fd3e3ce2@siemens.com Debugged-by: Vlastimil Babka Debugged-by: Kees Cook Reported-by: Jan Kiszka Fixes: f79c8e4136eac37255ead8875593ae33a2c16d20 ("ACPICA: Namespace: simplify creation of the initial/default namespace") Signed-off-by: Vegard Nossum --- drivers/acpi/acpica/nsaccess.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/acpi/acpica/nsaccess.c b/drivers/acpi/acpica/nsaccess.c index 3f045b5953b2e..1be9b34732ab8 100644 --- a/drivers/acpi/acpica/nsaccess.c +++ b/drivers/acpi/acpica/nsaccess.c @@ -98,14 +98,12 @@ acpi_status acpi_ns_root_initialize(void) * predefined names are at the root level. It is much easier to * just create and link the new node(s) here. */ - new_node = - ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_namespace_node)); + new_node = acpi_ns_create_node(*ACPI_CAST_PTR (u32, init_val->name)); if (!new_node) { status = AE_NO_MEMORY; goto unlock_and_exit; } - ACPI_COPY_NAMESEG(new_node->name.ascii, init_val->name); new_node->descriptor_type = ACPI_DESC_TYPE_NAMED; new_node->type = init_val->type; -- 2.16.1.72.g5be1f00a9.dirty