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

Status: premoderation: reported on 2025/04/26 10:29
Reported-by: syzbot+aa263e6e56f76eeacb80@syzkaller.appspotmail.com
First crash: 11d, last: 9h27m
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-54 KASAN: use-after-free Read in exact_lock 1 866d 866d 0/2 auto-obsoleted due to no activity on 2023/04/22 15:12
android-5-10 KASAN: use-after-free Read in exact_lock 53 64d 73d 0/2 auto-obsoleted due to no activity on 2025/04/24 06:37

Sample crash report:
BUG: KASAN: use-after-free in get_disk_and_module block/genhd.c:1787 [inline]
BUG: KASAN: use-after-free in exact_lock+0x38/0xc0 block/genhd.c:677
Read of size 8 at addr ffff888109605460 by task syz-executor/25124

CPU: 1 PID: 25124 Comm: syz-executor Tainted: G        W         5.10.237-syzkaller-00309-g7e2543346ff7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
 get_disk_and_module block/genhd.c:1787 [inline]
 exact_lock+0x38/0xc0 block/genhd.c:677
 kobj_lookup+0x298/0x430 drivers/base/map.c:119
 get_gendisk+0xe9/0x340 block/genhd.c:1001
 bdev_get_gendisk fs/block_dev.c:1110 [inline]
 __blkdev_get+0x1b0/0x12f0 fs/block_dev.c:1474
 blkdev_get fs/block_dev.c:1653 [inline]
 blkdev_open+0x208/0x430 fs/block_dev.c:1770
 do_dentry_open+0x793/0x1090 fs/open.c:819
 vfs_open+0x73/0x80 fs/open.c:942
 do_open fs/namei.c:3391 [inline]
 path_openat+0x27ad/0x3160 fs/namei.c:3509
 do_filp_open+0x1b3/0x3e0 fs/namei.c:3536
 do_sys_openat2+0x14c/0x6d0 fs/open.c:1217
 do_sys_open fs/open.c:1233 [inline]
 __do_sys_openat fs/open.c:1249 [inline]
 __se_sys_openat fs/open.c:1244 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1244
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f597425f251
Code: 75 57 89 f0 25 00 00 41 00 3d 00 00 41 00 74 49 80 3d fa 72 1f 00 00 74 6d 89 da 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 93 00 00 00 48 8b 54 24 28 64 48 2b 14 25
RSP: 002b:00007fff2f560c50 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f597425f251
RDX: 0000000000000002 RSI: 00007fff2f560d60 RDI: 00000000ffffff9c
RBP: 00007fff2f560d60 R08: 000000000000000a R09: 00007fff2f560a17
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007f597444f260 R14: 0000000000000003 R15: 00007fff2f560d60

Allocated by task 1:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:430 [inline]
 ____kasan_kmalloc mm/kasan/common.c:509 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518
 kasan_kmalloc include/linux/kasan.h:254 [inline]
 kmem_cache_alloc_trace+0x184/0x2e0 mm/slub.c:2974
 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline]
 kmalloc_node include/linux/slab.h:570 [inline]
 kzalloc_node include/linux/slab.h:675 [inline]
 __alloc_disk_node+0x79/0x580 block/genhd.c:1727
 loop_add+0x33f/0x7b0 drivers/block/loop.c:2158
 loop_init+0x1bf/0x1ff drivers/block/loop.c:2403
 do_one_initcall+0x187/0x510 init/main.c:1197
 do_initcall_level+0x16f/0x2cf init/main.c:1270
 do_initcalls+0x50/0x92 init/main.c:1286
 do_basic_setup+0x88/0x8f init/main.c:1306
 kernel_init_freeable+0x287/0x3be init/main.c:1510
 kernel_init+0x11/0x1a0 init/main.c:1397
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Freed by task 24525:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370
 kasan_slab_free include/linux/kasan.h:220 [inline]
 slab_free_hook mm/slub.c:1595 [inline]
 slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1621
 slab_free mm/slub.c:3203 [inline]
 kfree+0xc0/0x270 mm/slub.c:4191
 skb_free_head net/core/skbuff.c:606 [inline]
 skb_release_data+0x532/0x670 net/core/skbuff.c:626
 skb_release_all net/core/skbuff.c:680 [inline]
 __kfree_skb net/core/skbuff.c:694 [inline]
 kfree_skb+0xb9/0x2f0 net/core/skbuff.c:713
 ip6_mc_input+0x235/0x2a0 net/ipv6/ip6_input.c:574
 dst_input include/net/dst.h:461 [inline]
 ip6_rcv_finish+0x18c/0x360 net/ipv6/ip6_input.c:80
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ipv6_rcv+0xec/0x210 net/ipv6/ip6_input.c:301
 __netif_receive_skb_one_core net/core/dev.c:5402 [inline]
 __netif_receive_skb+0xc8/0x280 net/core/dev.c:5516
 process_backlog+0x368/0x600 net/core/dev.c:6423
 napi_poll net/core/dev.c:6874 [inline]
 net_rx_action+0x432/0xdd0 net/core/dev.c:6944
 __do_softirq+0x255/0x563 kernel/softirq.c:309

The buggy address belongs to the object at ffff888109605000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1120 bytes inside of
 2048-byte region [ffff888109605000, ffff888109605800)
The buggy address belongs to the page:
page:ffffea0004258000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109600
head:ffffea0004258000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 0000000000000000 0000000100000001 ffff888100042d80
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, ts 2062822433, free_ts 0
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5349
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1808 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1869
 new_slab_objects mm/slub.c:2627 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2791
 __slab_alloc+0x63/0xa0 mm/slub.c:2831
 slab_alloc_node mm/slub.c:2913 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 kmem_cache_alloc_trace+0x1b3/0x2e0 mm/slub.c:2972
 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline]
 kmalloc_node include/linux/slab.h:570 [inline]
 kzalloc_node include/linux/slab.h:675 [inline]
 bdi_alloc+0x4e/0x110 mm/backing-dev.c:746
 blk_alloc_queue+0x103/0x610 block/blk-core.c:535
 blk_mq_init_queue_data block/blk-mq.c:3155 [inline]
 blk_mq_init_queue+0x37/0xd0 block/blk-mq.c:3174
 loop_add+0x266/0x7b0 drivers/block/loop.c:2140
 loop_init+0x1bf/0x1ff drivers/block/loop.c:2403
 do_one_initcall+0x187/0x510 init/main.c:1197
 do_initcall_level+0x16f/0x2cf init/main.c:1270
 do_initcalls+0x50/0x92 init/main.c:1286
 do_basic_setup+0x88/0x8f init/main.c:1306
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888109605300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888109605380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888109605400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff888109605480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888109605500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (29):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/07 22:18 android13-5.10-lts 7e2543346ff7 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/06 18:58 android13-5.10-lts ab07aeb2c93d 350f4ffc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/06 14:49 android13-5.10-lts ab07aeb2c93d ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/06 09:54 android13-5.10-lts ab07aeb2c93d ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/06 03:10 android13-5.10-lts ab07aeb2c93d ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/05 07:57 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/05 04:03 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/05 04:00 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/05 02:39 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 23:22 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 21:27 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 21:25 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 15:30 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 14:46 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 14:11 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 12:05 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/04 11:51 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/03 12:41 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/03 08:48 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/02 18:35 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/02 18:35 android13-5.10-lts ab07aeb2c93d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/01 14:28 android13-5.10-lts ab07aeb2c93d 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/05/01 05:58 android13-5.10-lts ab07aeb2c93d ce7952f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/04/30 17:14 android13-5.10-lts ab07aeb2c93d 85a5a23f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/04/29 15:19 android13-5.10-lts ab07aeb2c93d aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/04/27 19:54 android13-5.10-lts ba8b8b193394 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/04/27 18:39 android13-5.10-lts ba8b8b193394 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/04/26 22:53 android13-5.10-lts ba8b8b193394 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
2025/04/26 10:28 android13-5.10-lts ba8b8b193394 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in exact_lock
* Struck through repros no longer work on HEAD.