upstream test error: KASAN: invalid-access Write in binder_add

Title	Replies (including bot)	Last reply
[syzbot] [kernel?] upstream test error: KASAN: invalid-access Write in binder_add_device	1 (2)	2025/05/06 09:07
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BUG: KASAN: invalid-access in hlist_add_head include/linux/list.h:1026 [inline]
BUG: KASAN: invalid-access in binder_add_device+0xf4/0xf8 drivers/android/binder.c:6932
Write of size 8 at addr d9f000001772ec08 by task syz-executor/3290
Pointer tag: [d9], memory tag: [85]

CPU: 0 UID: 0 PID: 3290 Comm: syz-executor Not tainted 6.14.0-rc2-syzkaller-g29281a76709c #0
Hardware name: linux,dummy-virt (DT)
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 print_address_description+0xac/0x290 mm/kasan/report.c:378
 print_report+0x84/0xa0 mm/kasan/report.c:489
 kasan_report+0xb0/0x110 mm/kasan/report.c:602
 kasan_tag_mismatch+0x28/0x3c mm/kasan/sw_tags.c:175
 __hwasan_tag_mismatch+0x30/0x60 arch/arm64/lib/kasan_sw_tags.S:55
 hlist_add_head include/linux/list.h:1026 [inline]
 binder_add_device+0xf4/0xf8 drivers/android/binder.c:6932
 binderfs_binder_device_create+0xbfc/0xc28 drivers/android/binderfs.c:210
 binderfs_fill_super+0xb30/0xe20 drivers/android/binderfs.c:729
 vfs_get_super fs/super.c:1280 [inline]
 get_tree_nodev+0xdc/0x1cc fs/super.c:1299
 binderfs_fs_context_get_tree+0x28/0x38 drivers/android/binderfs.c:749
 vfs_get_tree+0xc4/0x3cc fs/super.c:1814
 do_new_mount+0x2a0/0x988 fs/namespace.c:3560
 path_mount+0x650/0x101c fs/namespace.c:3887
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount fs/namespace.c:4088 [inline]
 __arm64_sys_mount+0x36c/0x468 fs/namespace.c:4088
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x90/0x2b4 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x180/0x2f4 arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x58/0x74 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x134 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x4df000001772e000 pfn:0x5772e
flags: 0x1ffde8000000000(node=0|zone=0|lastcpupid=0x7ff|kasantag=0x7a)
page_type: f2(table)
raw: 01ffde8000000000 0000000000000000 dead000000000122 0000000000000000
raw: 4df000001772e000 0000000000000000 00000001f2000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 fff000001772ea00: 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85
 fff000001772eb00: 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85
>fff000001772ec00: 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85
                   ^
 fff000001772ed00: 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85
 fff000001772ee00: 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85 85
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