Re: [PATCH] mm, kasan: don't poison boot memory
From: George Kennedy
Date: Thu Feb 25 2021 - 20:22:33 EST
On 2/25/2021 12:33 PM, George Kennedy wrote:
On 2/25/2021 11:07 AM, Mike Rapoport wrote:
On Thu, Feb 25, 2021 at 10:22:44AM -0500, George Kennedy wrote:
On 2/24/2021 5:37 AM, Mike Rapoport wrote:
Applied just your latest patch, but same failure.
I thought there was an earlier comment (which I can't find now) that
stated
that memblock_reserve() wouldn't reserve the page, which is what's
needed
here.
Actually, I think that memblock_reserve() should be just fine, but it
seems
I'm missing something in address calculation each time.
What would happen if you stuck
memblock_reserve(0xbe453000, PAGE_SIZE);
say, at the beginning of find_ibft_region()?
Good news Mike!
The above hack in yesterday's last patch works - 10 successful
reboots. See: "BE453" below for the hack.
I'll modify the patch to use "table_desc->address" instead, which is
the physical address of the table.
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 7bdc023..c118dd5 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1551,6 +1551,7 @@ void __init acpi_boot_table_init(void)
if (acpi_disabled)
return;
+#if 0
/*
* Initialize the ACPI boot-time table parser.
*/
@@ -1558,6 +1559,7 @@ void __init acpi_boot_table_init(void)
disable_acpi();
return;
}
+#endif
acpi_table_parse(ACPI_SIG_BOOT, acpi_parse_sbf);
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 740f3bdb..b045ab2 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -571,16 +571,6 @@ void __init reserve_standard_io_resources(void)
}
-static __init void reserve_ibft_region(void)
-{
- unsigned long addr, size = 0;
-
- addr = find_ibft_region(&size);
-
- if (size)
- memblock_reserve(addr, size);
-}
-
static bool __init snb_gfx_workaround_needed(void)
{
#ifdef CONFIG_PCI
@@ -1033,6 +1023,12 @@ void __init setup_arch(char **cmdline_p)
*/
find_smp_config();
+ /*
+ * Initialize the ACPI boot-time table parser.
+ */
+ if (acpi_table_init())
+ disable_acpi();
+
reserve_ibft_region();
early_alloc_pgt_buf();
diff --git a/drivers/firmware/iscsi_ibft_find.c
b/drivers/firmware/iscsi_ibft_find.c
index 64bb945..95fc1a6 100644
--- a/drivers/firmware/iscsi_ibft_find.c
+++ b/drivers/firmware/iscsi_ibft_find.c
@@ -47,7 +47,25 @@
#define VGA_MEM 0xA0000 /* VGA buffer */
#define VGA_SIZE 0x20000 /* 128kB */
-static int __init find_ibft_in_mem(void)
+static void __init *acpi_find_ibft_region(void)
+{
+ int i;
+ struct acpi_table_header *table = NULL;
+ acpi_status status;
+
+ if (acpi_disabled)
+ return NULL;
+
+ for (i = 0; i < ARRAY_SIZE(ibft_signs) && !ibft_addr; i++) {
+ status = acpi_get_table(ibft_signs[i].sign, 0, &table);
+ if (ACPI_SUCCESS(status))
+ return table;
+ }
+
+ return NULL;
+}
+
+static void __init *find_ibft_in_mem(void)
{
unsigned long pos;
unsigned int len = 0;
@@ -70,35 +88,52 @@ static int __init find_ibft_in_mem(void)
/* if the length of the table extends past 1M,
* the table cannot be valid. */
if (pos + len <= (IBFT_END-1)) {
- ibft_addr = (struct acpi_table_ibft *)virt;
pr_info("iBFT found at 0x%lx.\n", pos);
- goto done;
+ return virt;
}
}
}
}
-done:
- return len;
+
+ return NULL;
}
+
+static void __init *find_ibft(void)
+{
+ /* iBFT 1.03 section 1.4.3.1 mandates that UEFI machines will
+ * only use ACPI for this */
+ if (!efi_enabled(EFI_BOOT))
+ return find_ibft_in_mem();
+ else
+ return acpi_find_ibft_region();
+}
+
/*
* Routine used to find the iSCSI Boot Format Table. The logical
* kernel address is set in the ibft_addr global variable.
*/
-unsigned long __init find_ibft_region(unsigned long *sizep)
+void __init reserve_ibft_region(void)
{
- ibft_addr = NULL;
+ struct acpi_table_ibft *table;
+ unsigned long size;
- /* iBFT 1.03 section 1.4.3.1 mandates that UEFI machines will
- * only use ACPI for this */
+ table = find_ibft();
+ if (!table)
+ return;
- if (!efi_enabled(EFI_BOOT))
- find_ibft_in_mem();
-
- if (ibft_addr) {
- *sizep = PAGE_ALIGN(ibft_addr->header.length);
- return (u64)virt_to_phys(ibft_addr);
- }
+ size = PAGE_ALIGN(table->header.length);
+#if 0
+printk(KERN_ERR "XXX reserve_ibft_region: table=%llx,
virt_to_phys(table)=%llx, size=%lx\n",
+ (u64)table, virt_to_phys(table), size);
+ memblock_reserve(virt_to_phys(table), size);
+#else
+printk(KERN_ERR "XXX reserve_ibft_region: table=%llx,
0x00000000BE453000, size=%lx\n",
+ (u64)table, size);
+ memblock_reserve(0x00000000BE453000, size);
+#endif
- *sizep = 0;
- return 0;
+ if (efi_enabled(EFI_BOOT))
+ acpi_put_table(&table->header);
+ else
+ ibft_addr = table;
}
diff --git a/include/linux/iscsi_ibft.h b/include/linux/iscsi_ibft.h
index b7b45ca..da813c8 100644
--- a/include/linux/iscsi_ibft.h
+++ b/include/linux/iscsi_ibft.h
@@ -26,13 +26,9 @@
* mapped address is set in the ibft_addr variable.
*/
#ifdef CONFIG_ISCSI_IBFT_FIND
-unsigned long find_ibft_region(unsigned long *sizep);
+void reserve_ibft_region(void);
#else
-static inline unsigned long find_ibft_region(unsigned long *sizep)
-{
- *sizep = 0;
- return 0;
-}
+static inline void reserve_ibft_region(void) {}
#endif
#endif /* ISCSI_IBFT_H */
Mike,
To get rid of the 0x00000000BE453000 hardcoding, I added the following
patch to your above patch to get the iBFT table "address" to use with
memblock_reserve():
diff --git a/drivers/acpi/acpica/tbfind.c b/drivers/acpi/acpica/tbfind.c
index 56d81e4..4bc7bf3 100644
--- a/drivers/acpi/acpica/tbfind.c
+++ b/drivers/acpi/acpica/tbfind.c
@@ -120,3 +120,34 @@
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return_ACPI_STATUS(status);
}
+
+acpi_physical_address
+acpi_tb_find_table_address(char *signature)
+{
+ acpi_physical_address address = 0;
+ struct acpi_table_desc *table_desc;
+ int i;
+
+ ACPI_FUNCTION_TRACE(tb_find_table_address);
+
+printk(KERN_ERR "XXX acpi_tb_find_table_address: signature=%s\n",
signature);
+
+ (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
+ for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {
+ if (memcmp(&(acpi_gbl_root_table_list.tables[i].signature),
+ signature, ACPI_NAMESEG_SIZE)) {
+
+ /* Not the requested table */
+
+ continue;
+ }
+
+ /* Table with matching signature has been found */
+ table_desc = &acpi_gbl_root_table_list.tables[i];
+ address = table_desc->address;
+ }
+
+ (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
+printk(KERN_ERR "XXX acpi_tb_find_table_address(EXIT): address=%llx\n",
address);
+ return address;
+}
diff --git a/drivers/firmware/iscsi_ibft_find.c
b/drivers/firmware/iscsi_ibft_find.c
index 95fc1a6..0de70b4 100644
--- a/drivers/firmware/iscsi_ibft_find.c
+++ b/drivers/firmware/iscsi_ibft_find.c
@@ -28,6 +28,8 @@
#include <asm/mmzone.h>
+extern acpi_physical_address acpi_tb_find_table_address(char *signature);
+
/*
* Physical location of iSCSI Boot Format Table.
*/
@@ -116,24 +118,32 @@ void __init reserve_ibft_region(void)
{
struct acpi_table_ibft *table;
unsigned long size;
+ acpi_physical_address address;
table = find_ibft();
if (!table)
return;
size = PAGE_ALIGN(table->header.length);
+ address = acpi_tb_find_table_address(table->header.signature);
#if 0
printk(KERN_ERR "XXX reserve_ibft_region: table=%llx,
virt_to_phys(table)=%llx, size=%lx\n",
(u64)table, virt_to_phys(table), size);
memblock_reserve(virt_to_phys(table), size);
#else
-printk(KERN_ERR "XXX reserve_ibft_region: table=%llx,
0x00000000BE453000, size=%lx\n",
- (u64)table, size);
- memblock_reserve(0x00000000BE453000, size);
+printk(KERN_ERR "XXX reserve_ibft_region: table=%llx, address=%llx,
size=%lx\n",
+ (u64)table, address, size);
+ if (address)
+ memblock_reserve(address, size);
+ else
+ printk(KERN_ERR "%s: Can't find table address\n", __func__);
#endif
- if (efi_enabled(EFI_BOOT))
+ if (efi_enabled(EFI_BOOT)) {
+printk(KERN_ERR "XXX reserve_ibft_region: calling
acpi_put_table(%llx)\n", (u64)&table->header);
acpi_put_table(&table->header);
- else
+ } else {
ibft_addr = table;
+printk(KERN_ERR "XXX reserve_ibft_region: ibft_addr=%llx\n",
(u64)ibft_addr);
+ }
}
Debug from the above:
[ 0.050646] ACPI: Early table checksum verification disabled
[ 0.051778] ACPI: RSDP 0x00000000BFBFA014 000024 (v02 BOCHS )
[ 0.052922] ACPI: XSDT 0x00000000BFBF90E8 00004C (v01 BOCHS BXPCFACP
00000001 01000013)
[ 0.054623] ACPI: FACP 0x00000000BFBF5000 000074 (v01 BOCHS BXPCFACP
00000001 BXPC 00000001)
[ 0.056326] ACPI: DSDT 0x00000000BFBF6000 00238D (v01 BOCHS BXPCDSDT
00000001 BXPC 00000001)
[ 0.058016] ACPI: FACS 0x00000000BFBFD000 000040
[ 0.058940] ACPI: APIC 0x00000000BFBF4000 000090 (v01 BOCHS BXPCAPIC
00000001 BXPC 00000001)
[ 0.060627] ACPI: HPET 0x00000000BFBF3000 000038 (v01 BOCHS BXPCHPET
00000001 BXPC 00000001)
[ 0.062304] ACPI: BGRT 0x00000000BE49B000 000038 (v01 INTEL EDK2
00000002 01000013)
[ 0.063987] ACPI: iBFT 0x00000000BE453000 000800 (v01 BOCHS BXPCFACP
00000000 00000000)
[ 0.065683] XXX acpi_tb_find_table_address: signature=iBFT
[ 0.066754] XXX acpi_tb_find_table_address(EXIT): address=be453000
[ 0.067959] XXX reserve_ibft_region: table=ffffffffff240000,
address=be453000, size=1000
[ 0.069534] XXX reserve_ibft_region: calling
acpi_put_table(ffffffffff240000)
Not sure if it's the right thing to do, but added
"acpi_tb_find_table_address()" to return the physical address of a table
to use with memblock_reserve().
virt_to_phys(table) does not seem to return the physical address for the
iBFT table (it would be nice if struct acpi_table_header also had a
"address" element for the physical address of the table).
Ran 10 successful boots with the above without failure.
George
Debug from the above:
[ 0.020293] last_pfn = 0xbfedc max_arch_pfn = 0x400000000
[ 0.050778] ACPI: Early table checksum verification disabled
[ 0.056475] ACPI: RSDP 0x00000000BFBFA014 000024 (v02 BOCHS )
[ 0.057628] ACPI: XSDT 0x00000000BFBF90E8 00004C (v01 BOCHS
BXPCFACP 00000001 01000013)
[ 0.059341] ACPI: FACP 0x00000000BFBF5000 000074 (v01 BOCHS
BXPCFACP 00000001 BXPC 00000001)
[ 0.061043] ACPI: DSDT 0x00000000BFBF6000 00238D (v01 BOCHS
BXPCDSDT 00000001 BXPC 00000001)
[ 0.062740] ACPI: FACS 0x00000000BFBFD000 000040
[ 0.063673] ACPI: APIC 0x00000000BFBF4000 000090 (v01 BOCHS
BXPCAPIC 00000001 BXPC 00000001)
[ 0.065369] ACPI: HPET 0x00000000BFBF3000 000038 (v01 BOCHS
BXPCHPET 00000001 BXPC 00000001)
[ 0.067061] ACPI: BGRT 0x00000000BE49B000 000038 (v01 INTEL
EDK2 00000002 01000013)
[ 0.068761] ACPI: iBFT 0x00000000BE453000 000800 (v01 BOCHS
BXPCFACP 00000000 00000000)
[ 0.070461] XXX reserve_ibft_region: table=ffffffffff240000,
0x00000000BE453000, size=1000
[ 0.072231] check: Scanning 1 areas for low memory corruption
George
[ 30.308229] iBFT detected..
[ 30.308796]
==================================================================
[ 30.308890] BUG: KASAN: use-after-free in ibft_init+0x134/0xc33
[ 30.308890] Read of size 4 at addr ffff8880be453004 by task
swapper/0/1
[ 30.308890]
[ 30.308890] CPU: 1 PID: 1 Comm: swapper/0 Not tainted
5.11.0-f9593a0 #12
[ 30.308890] Hardware name: QEMU Standard PC (i440FX + PIIX,
1996), BIOS
0.0.0 02/06/2015
[ 30.308890] Call Trace:
[ 30.308890] dump_stack+0xdb/0x120
[ 30.308890] ? ibft_init+0x134/0xc33
[ 30.308890] print_address_description.constprop.7+0x41/0x60
[ 30.308890] ? ibft_init+0x134/0xc33
[ 30.308890] ? ibft_init+0x134/0xc33
[ 30.308890] kasan_report.cold.10+0x78/0xd1
[ 30.308890] ? ibft_init+0x134/0xc33
[ 30.308890] __asan_report_load_n_noabort+0xf/0x20
[ 30.308890] ibft_init+0x134/0xc33
[ 30.308890] ? write_comp_data+0x2f/0x90
[ 30.308890] ? ibft_check_initiator_for+0x159/0x159
[ 30.308890] ? write_comp_data+0x2f/0x90
[ 30.308890] ? ibft_check_initiator_for+0x159/0x159
[ 30.308890] do_one_initcall+0xc4/0x3e0
[ 30.308890] ? perf_trace_initcall_level+0x3e0/0x3e0
[ 30.308890] ? unpoison_range+0x14/0x40
[ 30.308890] ? ____kasan_kmalloc.constprop.5+0x8f/0xc0
[ 30.308890] ? kernel_init_freeable+0x420/0x652
[ 30.308890] ? __kasan_kmalloc+0x9/0x10
[ 30.308890] ? __sanitizer_cov_trace_pc+0x21/0x50
[ 30.308890] kernel_init_freeable+0x596/0x652
[ 30.308890] ? console_on_rootfs+0x7d/0x7d
[ 30.308890] ? __sanitizer_cov_trace_pc+0x21/0x50
[ 30.308890] ? rest_init+0xf0/0xf0
[ 30.308890] kernel_init+0x16/0x1d0
[ 30.308890] ? rest_init+0xf0/0xf0
[ 30.308890] ret_from_fork+0x22/0x30
[ 30.308890]
[ 30.308890] The buggy address belongs to the page:
[ 30.308890] page:0000000001b7b17c refcount:0 mapcount:0
mapping:0000000000000000 index:0x1 pfn:0xbe453
[ 30.308890] flags: 0xfffffc0000000()
[ 30.308890] raw: 000fffffc0000000 ffffea0002ef9788 ffffea0002f91488
0000000000000000
[ 30.308890] raw: 0000000000000001 0000000000000000 00000000ffffffff
0000000000000000
[ 30.308890] page dumped because: kasan: bad access detected
[ 30.308890] page_owner tracks the page as freed
[ 30.308890] page last allocated via order 0, migratetype Movable,
gfp_mask 0x100dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO), pid 204, ts
28121288605
[ 30.308890] prep_new_page+0xfb/0x140
[ 30.308890] get_page_from_freelist+0x3503/0x5730
[ 30.308890] __alloc_pages_nodemask+0x2d8/0x650
[ 30.308890] alloc_pages_vma+0xe2/0x560
[ 30.308890] __handle_mm_fault+0x930/0x26c0
[ 30.308890] handle_mm_fault+0x1f9/0x810
[ 30.308890] do_user_addr_fault+0x6f7/0xca0
[ 30.308890] exc_page_fault+0xaf/0x1a0
[ 30.308890] asm_exc_page_fault+0x1e/0x30
[ 30.308890] page last free stack trace:
[ 30.308890] free_pcp_prepare+0x122/0x290
[ 30.308890] free_unref_page_list+0xe6/0x490
[ 30.308890] release_pages+0x2ed/0x1270
[ 30.308890] free_pages_and_swap_cache+0x245/0x2e0
[ 30.308890] tlb_flush_mmu+0x11e/0x680
[ 30.308890] tlb_finish_mmu+0xa6/0x3e0
[ 30.308890] exit_mmap+0x2b3/0x540
[ 30.308890] mmput+0x11d/0x450
[ 30.308890] do_exit+0xaa6/0x2d40
[ 30.308890] do_group_exit+0x128/0x340
[ 30.308890] __x64_sys_exit_group+0x43/0x50
[ 30.308890] do_syscall_64+0x37/0x50
[ 30.308890] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 30.308890]
[ 30.308890] Memory state around the buggy address:
[ 30.308890] ffff8880be452f00: ff ff ff ff ff ff ff ff ff ff ff
ff ff ff
ff ff
[ 30.308890] ffff8880be452f80: ff ff ff ff ff ff ff ff ff ff ff
ff ff ff
ff ff
[ 30.308890] >ffff8880be453000: ff ff ff ff ff ff ff ff ff ff ff
ff ff ff
ff ff
[ 30.308890] ^
[ 30.308890] ffff8880be453080: ff ff ff ff ff ff ff ff ff ff ff
ff ff ff
ff ff
[ 30.308890] ffff8880be453100: ff ff ff ff ff ff ff ff ff ff ff
ff ff ff
ff ff
[ 30.308890]
==================================================================
George