[v5.15] KASAN: use-after-free Read in usb_udc_uevent

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2a910f4af54d Linux 5.15.139
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=154c739f680000
kernel config: https://syzkaller.appspot.com/x/.config?x=4901940b923cf2ea
dashboard link: https://syzkaller.appspot.com/bug?extid=ce20da4c71c171a3ae5c
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3635f683392f/disk-2a910f4a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e6fa88fc3919/vmlinux-2a910f4a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c376027e57f4/bzImage-2a910f4a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ce20da...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in usb_udc_uevent+0xaf/0x120 drivers/usb/gadget/udc/core.c:1771
Read of size 8 at addr ffff88807f3c6050 by task udevd/2963

CPU: 1 PID: 2963 Comm: udevd Not tainted 5.15.139-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
print_address_description+0x63/0x3b0 mm/kasan/report.c:248
__kasan_report mm/kasan/report.c:434 [inline]
kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
usb_udc_uevent+0xaf/0x120 drivers/usb/gadget/udc/core.c:1771
dev_uevent+0x4dc/0x8e0 drivers/base/core.c:2337
uevent_show+0x1a2/0x320 drivers/base/core.c:2393
dev_attr_show+0x50/0xb0 drivers/base/core.c:2095
sysfs_kf_seq_show+0x313/0x4e0 fs/sysfs/file.c:61
seq_read_iter+0x43a/0xd10 fs/seq_file.c:230
call_read_iter include/linux/fs.h:2097 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0xa9f/0xe10 fs/read_write.c:485
ksys_read+0x1a2/0x2c0 fs/read_write.c:623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f66dc6dfb6a
Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fffa26d4e28 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00005583186b0fd0 RCX: 00007f66dc6dfb6a
RDX: 0000000000001000 RSI: 00005583186ab950 RDI: 000000000000000c
RBP: 00005583186b0fd0 R08: 000000000000000c R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000003fff R14: 00007fffa26d5308 R15: 000000000000000a
</TASK>

Allocated by task 5514:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
kasan_kmalloc include/linux/kasan.h:264 [inline]
kmem_cache_alloc_trace+0x143/0x290 mm/slub.c:3247
kmalloc include/linux/slab.h:591 [inline]
kzalloc include/linux/slab.h:721 [inline]
dev_new drivers/usb/gadget/legacy/raw_gadget.c:191 [inline]
raw_open+0x88/0x4d0 drivers/usb/gadget/legacy/raw_gadget.c:387
misc_open+0x304/0x380 drivers/char/misc.c:141
chrdev_open+0x54a/0x630 fs/char_dev.c:414
do_dentry_open+0x807/0xfb0 fs/open.c:826
do_open fs/namei.c:3538 [inline]
path_openat+0x2702/0x2f20 fs/namei.c:3672
do_filp_open+0x21c/0x460 fs/namei.c:3699
do_sys_openat2+0x13b/0x500 fs/open.c:1211
do_sys_open fs/open.c:1227 [inline]
__do_sys_openat fs/open.c:1243 [inline]
__se_sys_openat fs/open.c:1238 [inline]
__x64_sys_openat+0x243/0x290 fs/open.c:1238
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 5513:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:1705 [inline]
slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
slab_free mm/slub.c:3499 [inline]
kfree+0xf1/0x270 mm/slub.c:4559
raw_release+0x134/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:426
__fput+0x3bf/0x890 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
__syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff88807f3c6000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 80 bytes inside of
4096-byte region [ffff88807f3c6000, ffff88807f3c7000)
The buggy address belongs to the page:
page:ffffea0001fcf000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f3c0
head:ffffea0001fcf000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011c42140
raw: 0000000000000000 0000000000040004 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 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1065, ts 323280584922, free_ts 323276232660
prep_new_page mm/page_alloc.c:2426 [inline]
get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
__alloc_pages+0x272/0x700 mm/page_alloc.c:5421
alloc_slab_page mm/slub.c:1775 [inline]
allocate_slab mm/slub.c:1912 [inline]
new_slab+0xbb/0x4b0 mm/slub.c:1975
___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
__slab_alloc mm/slub.c:3095 [inline]
slab_alloc_node mm/slub.c:3186 [inline]
__kmalloc_node_track_caller+0x1f6/0x390 mm/slub.c:4958
kmalloc_reserve net/core/skbuff.c:356 [inline]
__alloc_skb+0x12c/0x590 net/core/skbuff.c:427
alloc_skb include/linux/skbuff.h:1167 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:664 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline]
nsim_dev_trap_report_work+0x25e/0xab0 drivers/net/netdevsim/dev.c:762
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1340 [inline]
free_pcp_prepare mm/page_alloc.c:1391 [inline]
free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
free_slab mm/slub.c:2015 [inline]
discard_slab mm/slub.c:2021 [inline]
__unfreeze_partials+0x1b7/0x210 mm/slub.c:2507
put_cpu_partial+0x132/0x1a0 mm/slub.c:2587
do_slab_free mm/slub.c:3487 [inline]
___cache_free+0xe3/0x100 mm/slub.c:3506
qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176
kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
__kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
kasan_slab_alloc include/linux/kasan.h:254 [inline]
slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
slab_alloc_node mm/slub.c:3220 [inline]
kmem_cache_alloc_node_trace+0x128/0x2e0 mm/slub.c:3270
kmalloc_node include/linux/slab.h:609 [inline]
kzalloc_node include/linux/slab.h:732 [inline]
__get_vm_area_node+0x11f/0x2f0 mm/vmalloc.c:2416
__vmalloc_node_range+0xe3/0x8c0 mm/vmalloc.c:3019
__vmalloc_node mm/vmalloc.c:3079 [inline]
vzalloc+0x75/0x80 mm/vmalloc.c:3149
alloc_counters+0xcf/0x7d0 net/ipv4/netfilter/arp_tables.c:659
copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:839 [inline]
get_entries net/ipv6/netfilter/ip6_tables.c:1041 [inline]
do_ip6t_get_ctl+0xea8/0x1890 net/ipv6/netfilter/ip6_tables.c:1671
nf_getsockopt+0x28e/0x2b0 net/netfilter/nf_sockopt.c:116

Memory state around the buggy address:
ffff88807f3c5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88807f3c5f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807f3c6000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807f3c6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807f3c6100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.