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KASAN: use-after-free Read in get_max_inline_xattr_value_size (2)

Status: auto-obsoleted due to no activity on 2023/10/31 04:10
Reported-by: syzbot+4d9e1952e516bf404bfe@syzkaller.appspotmail.com
First crash: 936d, last: 928d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 KASAN: slab-out-of-bounds Read in get_max_inline_xattr_value_size ext4 19 C error 4 1047d 1126d 2/2 fixed on 2023/06/07 17:22
upstream KASAN: slab-out-of-bounds Read in get_max_inline_xattr_value_size ext4 19 C 21 1005d 1043d 22/29 fixed on 2023/07/01 16:05
android-54 KASAN: use-after-free Read in get_max_inline_xattr_value_size ext4 19 C 20 1047d 1126d 2/2 fixed on 2023/06/07 17:22
android-6-1 KASAN: use-after-free Read in get_max_inline_xattr_value_size origin:lts 19 C error done 10 848d 936d 0/2 auto-obsoleted due to no activity on 2024/01/19 14:48
android-5-15 KASAN: use-after-free Read in get_max_inline_xattr_value_size ext4 19 C error 4 1047d 1126d 2/2 fixed on 2023/06/07 17:22
linux-4.19 KASAN: slab-out-of-bounds Read in get_max_inline_xattr_value_size ext4 17 C error 1 1105d 1105d 0/1 upstream: reported C repro on 2023/01/27 02:26
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2023/08/21 18:21 19m retest repro android12-5.4 OK log

Sample crash report:
EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue
EXT4-fs error (device loop0): ext4_xattr_ibody_get:617: inode #18: comm syz-executor197: corrupted in-inode xattr
==================================================================
BUG: KASAN: use-after-free in get_max_inline_xattr_value_size+0x369/0x510 fs/ext4/inline.c:61
Read of size 4 at addr ffff8881dc88e004 by task syz-executor197/379

CPU: 0 PID: 379 Comm: syz-executor197 Not tainted 5.4.242-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x600 mm/kasan/report.c:384
 __kasan_report+0xf3/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 get_max_inline_xattr_value_size+0x369/0x510 fs/ext4/inline.c:61
 ext4_get_max_inline_size+0x134/0x1f0 fs/ext4/inline.c:112
 ext4_try_to_write_inline_data+0xda/0x1720 fs/ext4/inline.c:672
 ext4_write_begin+0x25a/0x1900 fs/ext4/inode.c:1314
 ext4_da_write_begin+0x4a3/0xfe0 fs/ext4/inode.c:3120
 generic_perform_write+0x2c7/0x560 mm/filemap.c:3311
 __generic_file_write_iter+0x224/0x530 mm/filemap.c:3440
 ext4_file_write_iter+0x499/0x10e0 fs/ext4/file.c:270
 call_write_iter include/linux/fs.h:1981 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0x5d3/0x750 fs/read_write.c:496
 vfs_write+0x206/0x4e0 fs/read_write.c:558
 ksys_write+0x199/0x2c0 fs/read_write.c:611
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Allocated by task 350:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842
 skb_clone+0x1c0/0x360 net/core/skbuff.c:1467
 dev_queue_xmit_nit+0x258/0xa10 net/core/dev.c:1966
 xmit_one net/core/dev.c:3207 [inline]
 dev_hard_start_xmit+0x12b/0x6b0 net/core/dev.c:3227
 sch_direct_xmit+0x28f/0xa10 net/sched/sch_generic.c:336
 qdisc_restart net/sched/sch_generic.c:401 [inline]
 __qdisc_run+0xa14/0x1e80 net/sched/sch_generic.c:409
 qdisc_run+0xf8/0x300 include/net/pkt_sched.h:122
 __dev_xmit_skb net/core/dev.c:3403 [inline]
 __dev_queue_xmit+0xb43/0x27e0 net/core/dev.c:3758
 neigh_hh_output include/net/neighbour.h:509 [inline]
 neigh_output include/net/neighbour.h:523 [inline]
 ip_finish_output2+0xb4f/0xfc0 net/ipv4/ip_output.c:236
 NF_HOOK_COND include/linux/netfilter.h:297 [inline]
 ip_output+0x19b/0x3a0 net/ipv4/ip_output.c:440
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xfaa/0x1850 net/ipv4/ip_output.c:541
 __tcp_transmit_skb+0x1de5/0x3390 net/ipv4/tcp_output.c:1180
 tcp_transmit_skb net/ipv4/tcp_output.c:1196 [inline]
 tcp_write_xmit+0x17b0/0x5cd0 net/ipv4/tcp_output.c:2467
 __tcp_push_pending_frames+0x91/0x2e0 net/ipv4/tcp_output.c:2648
 tcp_sendmsg_locked+0x2fff/0x3810 net/ipv4/tcp.c:1417
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1447
 sock_sendmsg_nosec net/socket.c:638 [inline]
 sock_sendmsg net/socket.c:658 [inline]
 sock_write_iter+0x344/0x470 net/socket.c:990
 call_write_iter include/linux/fs.h:1981 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0x5d3/0x750 fs/read_write.c:496
 vfs_write+0x206/0x4e0 fs/read_write.c:558
 ksys_write+0x199/0x2c0 fs/read_write.c:611
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 350:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096
 packet_rcv+0x13b/0x1170 net/packet/af_packet.c:2168
 dev_queue_xmit_nit+0x976/0xa10 net/core/dev.c:1998
 xmit_one net/core/dev.c:3207 [inline]
 dev_hard_start_xmit+0x12b/0x6b0 net/core/dev.c:3227
 sch_direct_xmit+0x28f/0xa10 net/sched/sch_generic.c:336
 qdisc_restart net/sched/sch_generic.c:401 [inline]
 __qdisc_run+0xa14/0x1e80 net/sched/sch_generic.c:409
 qdisc_run+0xf8/0x300 include/net/pkt_sched.h:122
 __dev_xmit_skb net/core/dev.c:3403 [inline]
 __dev_queue_xmit+0xb43/0x27e0 net/core/dev.c:3758
 neigh_hh_output include/net/neighbour.h:509 [inline]
 neigh_output include/net/neighbour.h:523 [inline]
 ip_finish_output2+0xb4f/0xfc0 net/ipv4/ip_output.c:236
 NF_HOOK_COND include/linux/netfilter.h:297 [inline]
 ip_output+0x19b/0x3a0 net/ipv4/ip_output.c:440
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xfaa/0x1850 net/ipv4/ip_output.c:541
 __tcp_transmit_skb+0x1de5/0x3390 net/ipv4/tcp_output.c:1180
 tcp_transmit_skb net/ipv4/tcp_output.c:1196 [inline]
 tcp_write_xmit+0x17b0/0x5cd0 net/ipv4/tcp_output.c:2467
 __tcp_push_pending_frames+0x91/0x2e0 net/ipv4/tcp_output.c:2648
 tcp_sendmsg_locked+0x2fff/0x3810 net/ipv4/tcp.c:1417
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1447
 sock_sendmsg_nosec net/socket.c:638 [inline]
 sock_sendmsg net/socket.c:658 [inline]
 sock_write_iter+0x344/0x470 net/socket.c:990
 call_write_iter include/linux/fs.h:1981 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0x5d3/0x750 fs/read_write.c:496
 vfs_write+0x206/0x4e0 fs/read_write.c:558
 ksys_write+0x199/0x2c0 fs/read_write.c:611
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

The buggy address belongs to the object at ffff8881dc88e000
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 4 bytes inside of
 240-byte region [ffff8881dc88e000, ffff8881dc88e0f0)
The buggy address belongs to the page:
page:ffffea0007722380 refcount:1 mapcount:0 mapping:ffff8881f1cd8c80 index:0x0
flags: 0x8000000000000200(slab)
raw: 8000000000000200 dead000000000100 dead000000000122 ffff8881f1cd8c80
raw: 0000000000000000 00000000000c000c 00000001ffffffff 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 0x12a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4891
 alloc_slab_page+0x39/0x3c0 mm/slub.c:343
 allocate_slab mm/slub.c:1683 [inline]
 new_slab+0x97/0x440 mm/slub.c:1749
 new_slab_objects mm/slub.c:2505 [inline]
 ___slab_alloc+0x2fe/0x490 mm/slub.c:2667
 __slab_alloc+0x62/0xa0 mm/slub.c:2707
 slab_alloc_node mm/slub.c:2792 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0x109/0x250 mm/slub.c:2842
 skb_clone+0x1c0/0x360 net/core/skbuff.c:1467
 dev_queue_xmit_nit+0x258/0xa10 net/core/dev.c:1966
 xmit_one net/core/dev.c:3207 [inline]
 dev_hard_start_xmit+0x12b/0x6b0 net/core/dev.c:3227
 sch_direct_xmit+0x28f/0xa10 net/sched/sch_generic.c:336
 qdisc_restart net/sched/sch_generic.c:401 [inline]
 __qdisc_run+0xa14/0x1e80 net/sched/sch_generic.c:409
 qdisc_run+0xf8/0x300 include/net/pkt_sched.h:122
 __dev_xmit_skb net/core/dev.c:3403 [inline]
 __dev_queue_xmit+0xb43/0x27e0 net/core/dev.c:3758
 neigh_hh_output include/net/neighbour.h:509 [inline]
 neigh_output include/net/neighbour.h:523 [inline]
 ip_finish_output2+0xb4f/0xfc0 net/ipv4/ip_output.c:236
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 free_pcp_prepare mm/page_alloc.c:1233 [inline]
 free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085
 free_unref_page_list+0x10a/0x590 mm/page_alloc.c:3154
 release_pages+0xad8/0xb20 mm/swap.c:842
 pagevec_lru_move_fn+0x1cb/0x250 mm/swap.c:215
 __pagevec_lru_add mm/swap.c:966 [inline]
 lru_add_drain_cpu+0x105/0x600 mm/swap.c:594
 lru_add_drain mm/swap.c:689 [inline]
 __pagevec_release+0x6e/0x150 mm/swap.c:859
 pagevec_release include/linux/pagevec.h:88 [inline]
 shmem_undo_range+0x8a5/0x1ad0 mm/shmem.c:875
 shmem_truncate_range mm/shmem.c:997 [inline]
 shmem_evict_inode+0x218/0x9a0 mm/shmem.c:1097
 evict+0x29b/0x6a0 fs/inode.c:575
 __dentry_kill+0x429/0x630 fs/dcache.c:579
 dentry_kill+0xb8/0x280 fs/dcache.c:673
 dput+0x154/0x2f0 fs/dcache.c:859
 do_renameat2+0x9bd/0x1110 fs/namei.c:4712
 __do_sys_rename fs/namei.c:4754 [inline]
 __se_sys_rename fs/namei.c:4752 [inline]
 __x64_sys_rename+0x64/0x70 fs/namei.c:4752
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881dc88df00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881dc88df80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881dc88e000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8881dc88e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff8881dc88e100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
==================================================================
EXT4-fs error (device loop0): ext4_read_block_bitmap_nowait:430: comm syz-executor197: Invalid block bitmap block 4294967295 in block_group 0

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/07/15 09:35 android12-5.4 6d5c2c1877e5 35d9ecc5 .config strace log report syz C [mounted in repro] ci2-android-5-4-kasan KASAN: use-after-free Read in get_max_inline_xattr_value_size
2023/07/23 04:10 android12-5.4 14e059a4e07a 27cbe77f .config console log report info ci2-android-5-4-kasan KASAN: use-after-free Read in get_max_inline_xattr_value_size
2023/07/15 09:45 android12-5.4 6d5c2c1877e5 35d9ecc5 .config console log report info ci2-android-5-4-kasan KASAN: use-after-free Read in get_max_inline_xattr_value_size
* Struck through repros no longer work on HEAD.