KASAN: slab-out-of-bounds Read in key_task

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KASAN: slab-out-of-bounds Read in key_task_permission (2) lsm keyrings				1	307d	303d	0/28	auto-obsoleted due to no activity on 2024/05/28 00:19
android-5-10	KASAN: use-after-free Read in key_task_permission				1	361d	361d	0/2	auto-obsoleted due to no activity on 2024/03/25 05:21
==================================================================
BUG: KASAN: slab-out-of-bounds in __kuid_val include/linux/uidgid.h:36 [inline]
BUG: KASAN: slab-out-of-bounds in uid_eq include/linux/uidgid.h:63 [inline]
BUG: KASAN: slab-out-of-bounds in key_task_permission+0x38f/0x400 security/keys/permission.c:54
Read of size 4 at addr ffff88802b641ba0 by task syz-executor.2/31965

CPU: 0 PID: 31965 Comm: syz-executor.2 Not tainted 6.4.0-syzkaller-12155-ga452483508d7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:364
 print_report mm/kasan/report.c:475 [inline]
 kasan_report+0x11d/0x130 mm/kasan/report.c:588
 __kuid_val include/linux/uidgid.h:36 [inline]
 uid_eq include/linux/uidgid.h:63 [inline]
 key_task_permission+0x38f/0x400 security/keys/permission.c:54
 search_nested_keyrings+0x889/0xe30 security/keys/keyring.c:793
 keyring_search_rcu+0x1b1/0x310 security/keys/keyring.c:922
 search_cred_keyrings_rcu+0x19d/0x2e0 security/keys/process_keys.c:480
 search_process_keyrings_rcu+0x1c/0x320 security/keys/process_keys.c:544
 lookup_user_key+0x10ce/0x12a0 security/keys/process_keys.c:762
 dh_data_from_key+0x26/0x2d0 security/keys/dh.c:25
 __keyctl_dh_compute+0x2fb/0xfd0 security/keys/dh.c:186
 keyctl_dh_compute+0xc3/0x130 security/keys/dh.c:312
 __do_sys_keyctl+0x3d0/0x610 security/keys/keyctl.c:1973
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f297988c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f29783fe168 EFLAGS: 00000246 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 00007f29799abf80 RCX: 00007f297988c389
RDX: 0000000020000340 RSI: 0000000020000300 RDI: 0000000000000017
RBP: 00007f29798d7493 R08: 0000000020000440 R09: 0000000000000000
R10: 000000000000009a R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdbca7492f R14: 00007f29783fe300 R15: 0000000000022000
 </TASK>

Allocated by task 5029:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 ____kasan_kmalloc mm/kasan/common.c:333 [inline]
 __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:196 [inline]
 __do_kmalloc_node mm/slab_common.c:985 [inline]
 __kmalloc_node+0x61/0x1a0 mm/slab_common.c:992
 kmalloc_array_node include/linux/slab.h:680 [inline]
 kcalloc_node include/linux/slab.h:685 [inline]
 memcg_alloc_slab_cgroups+0xee/0x1e0 mm/memcontrol.c:2899
 account_slab mm/slab.h:636 [inline]
 kmem_getpages mm/slab.c:1364 [inline]
 cache_grow_begin+0x331/0x3b0 mm/slab.c:2550
 cache_alloc_refill+0x289/0x3a0 mm/slab.c:2923
 ____cache_alloc mm/slab.c:2999 [inline]
 ____cache_alloc mm/slab.c:2982 [inline]
 __do_cache_alloc mm/slab.c:3182 [inline]
 slab_alloc_node mm/slab.c:3230 [inline]
 slab_alloc mm/slab.c:3246 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3423 [inline]
 kmem_cache_alloc+0x397/0x3f0 mm/slab.c:3432
 dup_fd+0x8d/0xcf0 fs/file.c:324
 copy_files kernel/fork.c:1791 [inline]
 copy_process+0x263b/0x75c0 kernel/fork.c:2491
 kernel_clone+0xeb/0x890 kernel/fork.c:2911
 __do_sys_clone+0xba/0x100 kernel/fork.c:3054
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88802b641b80
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes to the right of
 allocated 32-byte region [ffff88802b641b80, ffff88802b641ba0)

The buggy address belongs to the physical page:
page:ffffea0000ad9040 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802b641fc1 pfn:0x2b641
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0x32()
raw: 00fff00000000200 ffff888012840100 ffffea0001d7d190 ffffea00008accd0
raw: ffff88802b641fc1 ffff88802b641000 0000000100000032 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 5255, tgid 5252 (syz-executor.0), ts 84711792979, free_ts 78893243407
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1570
 prep_new_page mm/page_alloc.c:1577 [inline]
 get_page_from_freelist+0xfed/0x2d30 mm/page_alloc.c:3221
 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4477
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 kmem_getpages mm/slab.c:1356 [inline]
 cache_grow_begin+0x9b/0x3b0 mm/slab.c:2550
 cache_alloc_refill+0x289/0x3a0 mm/slab.c:2923
 ____cache_alloc mm/slab.c:2999 [inline]
 ____cache_alloc mm/slab.c:2982 [inline]
 __do_cache_alloc mm/slab.c:3182 [inline]
 slab_alloc_node mm/slab.c:3230 [inline]
 __kmem_cache_alloc_node+0x392/0x410 mm/slab.c:3521
 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1076
 kmalloc include/linux/slab.h:582 [inline]
 kzalloc include/linux/slab.h:703 [inline]
 alloc_workqueue_attrs kernel/workqueue.c:3707 [inline]
 alloc_workqueue+0x8be/0x1110 kernel/workqueue.c:4651
 nci_register_device+0x370/0xb50 net/nfc/nci/core.c:1233
 virtual_ncidev_open+0x14f/0x230 drivers/nfc/virtual_ncidev.c:148
 misc_open+0x383/0x4a0 drivers/char/misc.c:165
 chrdev_open+0x273/0x780 fs/char_dev.c:414
 do_dentry_open+0x6ce/0x17b0 fs/open.c:914
 do_open fs/namei.c:3636 [inline]
 path_openat+0x1b65/0x2710 fs/namei.c:3793
 do_filp_open+0x1ba/0x410 fs/namei.c:3820
 do_sys_openat2+0x160/0x1c0 fs/open.c:1407
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1161 [inline]
 free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2348
 free_unref_page+0x33/0x370 mm/page_alloc.c:2443
 slab_destroy mm/slab.c:1608 [inline]
 slabs_destroy+0x85/0xc0 mm/slab.c:1628
 cache_flusharray mm/slab.c:3341 [inline]
 ___cache_free+0x2c5/0x410 mm/slab.c:3404
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x4f/0x1a0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x195/0x220 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:186 [inline]
 slab_post_alloc_hook mm/slab.h:750 [inline]
 slab_alloc_node mm/slab.c:3237 [inline]
 __kmem_cache_alloc_node+0x206/0x410 mm/slab.c:3521
 __do_kmalloc_node mm/slab_common.c:984 [inline]
 __kmalloc+0x4e/0x190 mm/slab_common.c:998
 kmalloc include/linux/slab.h:586 [inline]
 tomoyo_realpath_from_path+0xc3/0x600 security/tomoyo/realpath.c:251
 tomoyo_realpath_nofollow+0xcc/0xe0 security/tomoyo/realpath.c:304
 tomoyo_find_next_domain+0x28d/0x1ff0 security/tomoyo/domain.c:727
 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:101 [inline]
 tomoyo_bprm_check_security+0x139/0x1d0 security/tomoyo/tomoyo.c:91
 security_bprm_check+0x49/0xb0 security/security.c:1102
 search_binary_handler fs/exec.c:1726 [inline]
 exec_binprm fs/exec.c:1780 [inline]
 bprm_execve fs/exec.c:1855 [inline]
 bprm_execve+0x740/0x1980 fs/exec.c:1811
 kernel_execve+0x3ee/0x500 fs/exec.c:2023

Memory state around the buggy address:
 ffff88802b641a80: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc
 ffff88802b641b00: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
>ffff88802b641b80: 00 00 00 00 fc fc fc fc 00 fc fc fc fc fc fc fc
                               ^
 ffff88802b641c00: fb fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff88802b641c80: 00 00 fc fc fc fc fc fc 00 00 fc fc fc fc fc fc
==================================================================