RE: [PATCH v6] mm/alloc_tag: Fix panic when CONFIG_KASAN enabled and CONFIG_KASAN_VMALLOC not enabled
From: Adrian Huang12
Date: Thu Dec 12 2024 - 09:08:11 EST
> -----Original Message-----
> From: owner-linux-mm@xxxxxxxxx <owner-linux-mm@xxxxxxxxx> On Behalf
> Of Hao Ge
> Sent: Thursday, December 12, 2024 3:21 PM
> To: surenb@xxxxxxxxxx; kent.overstreet@xxxxxxxxx;
> akpm@xxxxxxxxxxxxxxxxxxxx
> Cc: linux-mm@xxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; hao.ge@xxxxxxxxx;
> Hao Ge <gehao@xxxxxxxxxx>; Ben Greear <greearb@xxxxxxxxxxxxxxx>
> Subject: [External] [PATCH v6] mm/alloc_tag: Fix panic when CONFIG_KASAN
> enabled and CONFIG_KASAN_VMALLOC not enabled
>
> From: Hao Ge <gehao@xxxxxxxxxx>
>
> When CONFIG_KASAN is enabled but CONFIG_KASAN_VMALLOC is not
> enabled, we may encounter a panic during system boot.
>
> Because we haven't allocated pages and created mappings for the shadow
> memory corresponding to module allocation tags region,similar to how it is
> done for execmem_vmalloc.
>
> The memory for module allocation tags is allocated on demand, therefore we
> need to allocate shadow memory on demand as well in MODULE_ALIGN
> blocks.
>
> Here is the log for panic:
>
> [ 18.349421] BUG: unable to handle page fault for address: fffffbfff8092000
> [ 18.350016] #PF: supervisor read access in kernel mode
> [ 18.350459] #PF: error_code(0x0000) - not-present page
> [ 18.350904] PGD 20fe52067 P4D 219dc8067 PUD 219dc4067 PMD
> 102495067 PTE 0
> [ 18.351484] Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI
> [ 18.351961] CPU: 5 UID: 0 PID: 1 Comm: systemd Not tainted 6.13.0-rc1+ #3
> [ 18.352533] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
> [ 18.353494] RIP: 0010:kasan_check_range+0xba/0x1b0
> [ 18.353931] Code: 8d 5a 07 4c 0f 49 da 49 c1 fb 03 45 85 db 0f 84 dd 00 00
> 00 45 89 db 4a 8d 14 d8 eb 0d 48 83 c0 08 48 39 c2 0f 84 c1 00 00 00 <48> 83 38
> 00 74 ed 48 8d 50 08 eb 0d 48 83 c0 01 48 39 d0 0f 84 90
> [ 18.355484] RSP: 0018:ff11000101877958 EFLAGS: 00010206
> [ 18.355937] RAX: fffffbfff8092000 RBX: fffffbfff809201e RCX: ffffffff82a7ceac
> [ 18.356542] RDX: fffffbfff8092018 RSI: 00000000000000f0 RDI:
> ffffffffc0490000
> [ 18.357153] RBP: fffffbfff8092000 R08: 0000000000000001 R09:
> fffffbfff809201d
> [ 18.357756] R10: ffffffffc04900ef R11: 0000000000000003 R12:
> ffffffffc0490000
> [ 18.358365] R13: ff11000101877b48 R14: ffffffffc0490000 R15:
> 000000000000002c
> [ 18.358968] FS: 00007f9bd13c5940(0000) GS:ff110001eb480000(0000)
> knlGS:0000000000000000
> [ 18.359648] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 18.360178] CR2: fffffbfff8092000 CR3: 0000000109214004 CR4:
> 0000000000771ef0
> [ 18.360790] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> 0000000000000000
> [ 18.361404] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
> 0000000000000400
> [ 18.362020] PKRU: 55555554
> [ 18.362261] Call Trace:
> [ 18.362481] <TASK>
> [ 18.362671] ? __die+0x23/0x70
> [ 18.362964] ? page_fault_oops+0xc2/0x160
> [ 18.363318] ? exc_page_fault+0xad/0xc0
> [ 18.363680] ? asm_exc_page_fault+0x26/0x30
> [ 18.364056] ? move_module+0x3cc/0x8a0
> [ 18.364398] ? kasan_check_range+0xba/0x1b0
> [ 18.364755] __asan_memcpy+0x3c/0x60
> [ 18.365074] move_module+0x3cc/0x8a0
> [ 18.365386] layout_and_allocate.constprop.0+0x3d5/0x720
> [ 18.365841] ? early_mod_check+0x3dc/0x510
> [ 18.366195] load_module+0x72/0x1850
> [ 18.366509] ? __pfx_kernel_read_file+0x10/0x10
> [ 18.366918] ? vm_mmap_pgoff+0x21c/0x2d0
> [ 18.367262] init_module_from_file+0xd1/0x130
> [ 18.367638] ? __pfx_init_module_from_file+0x10/0x10
> [ 18.368073] ? __pfx__raw_spin_lock+0x10/0x10
> [ 18.368456] ? __pfx_cred_has_capability.isra.0+0x10/0x10
> [ 18.368938] idempotent_init_module+0x22c/0x790
> [ 18.369332] ? simple_getattr+0x6f/0x120
> [ 18.369676] ? __pfx_idempotent_init_module+0x10/0x10
> [ 18.370110] ? fdget+0x58/0x3a0
> [ 18.370393] ? security_capable+0x64/0xf0
> [ 18.370745] __x64_sys_finit_module+0xc2/0x140
> [ 18.371136] do_syscall_64+0x7d/0x160
> [ 18.371459] ? fdget_pos+0x1c8/0x4c0
> [ 18.371784] ? ksys_read+0xfd/0x1d0
> [ 18.372106] ? syscall_exit_to_user_mode+0x10/0x1f0
> [ 18.372525] ? do_syscall_64+0x89/0x160
> [ 18.372860] ? do_syscall_64+0x89/0x160
> [ 18.373194] ? do_syscall_64+0x89/0x160
> [ 18.373527] ? syscall_exit_to_user_mode+0x10/0x1f0
> [ 18.373952] ? do_syscall_64+0x89/0x160
> [ 18.374283] ? syscall_exit_to_user_mode+0x10/0x1f0
> [ 18.374701] ? do_syscall_64+0x89/0x160
> [ 18.375037] ? do_user_addr_fault+0x4a8/0xa40
> [ 18.375416] ? clear_bhb_loop+0x25/0x80
> [ 18.375748] ? clear_bhb_loop+0x25/0x80
> [ 18.376119] ? clear_bhb_loop+0x25/0x80
> [ 18.376450] entry_SYSCALL_64_after_hwframe+0x76/0x7e
>
> Fixes: 233e89322cbe ("alloc_tag: fix module allocation tags populated area
> calculation")
> Reported-by: Ben Greear <greearb@xxxxxxxxxxxxxxx>
> Closes: https://lore.kernel.org/all/1ba0cc57-e2ed-caa2-1241-aa5615bee01f@xxxxxxxxxxxxxxx/
> Suggested-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Acked-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Signed-off-by: Hao Ge <gehao@xxxxxxxxxx>
Thanks for the fix.
I encountered this issue recently and confirmed that this patch fixes it.
Feel free to my add my tested-by.
Tested-by: Adrian Huang <ahuang12@xxxxxxxxxx>
-- Adrian