[syzbot] [bpf?] [trace?] KASAN: slab-use-after-free Read in bpf_trace_run1

From: syzbot
Date: Mon Mar 25 2024 - 03:21:01 EST


Hello,

syzbot found the following issue on:

HEAD commit: 520fad2e3206 selftests/bpf: scale benchmark counting by us..
git tree: bpf-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=105af946180000
kernel config: https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
dashboard link: https://syzkaller.appspot.com/bug?extid=981935d9485a560bfbcb
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=114f17a5180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162bb7a5180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4eef3506c5ce/disk-520fad2e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/24d60ebe76cc/vmlinux-520fad2e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8f883e706550/bzImage-520fad2e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+981935d9485a560bfbcb@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: slab-use-after-free in __bpf_trace_run kernel/trace/bpf_trace.c:2376 [inline]
BUG: KASAN: slab-use-after-free in bpf_trace_run1+0xcb/0x510 kernel/trace/bpf_trace.c:2430
Read of size 8 at addr ffff8880290d9918 by task migration/0/19

CPU: 0 PID: 19 Comm: migration/0 Not tainted 6.8.0-syzkaller-05233-g520fad2e3206 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Stopper: 0x0 <- 0x0
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
__bpf_trace_run kernel/trace/bpf_trace.c:2376 [inline]
bpf_trace_run1+0xcb/0x510 kernel/trace/bpf_trace.c:2430
__traceiter_rcu_utilization+0x74/0xb0 include/trace/events/rcu.h:27
trace_rcu_utilization+0x194/0x1c0 include/trace/events/rcu.h:27
rcu_note_context_switch+0xc7c/0xff0 kernel/rcu/tree_plugin.h:360
__schedule+0x345/0x4a20 kernel/sched/core.c:6635
__schedule_loop kernel/sched/core.c:6813 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6828
smpboot_thread_fn+0x61e/0xa30 kernel/smpboot.c:160
kthread+0x2f0/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
</TASK>

Allocated by task 5075:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
kasan_kmalloc include/linux/kasan.h:211 [inline]
kmalloc_trace+0x1d9/0x360 mm/slub.c:4012
kmalloc include/linux/slab.h:590 [inline]
kzalloc include/linux/slab.h:711 [inline]
bpf_raw_tp_link_attach+0x2a0/0x6e0 kernel/bpf/syscall.c:3816
bpf_raw_tracepoint_open+0x1c2/0x240 kernel/bpf/syscall.c:3863
__sys_bpf+0x3c0/0x810 kernel/bpf/syscall.c:5673
__do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75

Freed by task 5075:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:589
poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240
__kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4299 [inline]
kfree+0x14a/0x380 mm/slub.c:4409
bpf_link_release+0x3b/0x50 kernel/bpf/syscall.c:3071
__fput+0x429/0x8a0 fs/file_table.c:423
task_work_run+0x24f/0x310 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0xa1b/0x27e0 kernel/exit.c:878
do_group_exit+0x207/0x2c0 kernel/exit.c:1027
__do_sys_exit_group kernel/exit.c:1038 [inline]
__se_sys_exit_group kernel/exit.c:1036 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75

The buggy address belongs to the object at ffff8880290d9900
which belongs to the cache kmalloc-128 of size 128
The buggy address is located 24 bytes inside of
freed 128-byte region [ffff8880290d9900, ffff8880290d9980)

The buggy address belongs to the physical page:
page:ffffea0000a43640 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x290d9
anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888014c418c0 0000000000000000 0000000000000001
raw: 0000000000000000 0000000000100010 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 4527, tgid 4527 (udevd), ts 43150902736, free_ts 43094996342
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533
prep_new_page mm/page_alloc.c:1540 [inline]
get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311
__alloc_pages+0x256/0x680 mm/page_alloc.c:4569
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page+0x5f/0x160 mm/slub.c:2190
allocate_slab mm/slub.c:2354 [inline]
new_slab+0x84/0x2f0 mm/slub.c:2407
___slab_alloc+0xd1b/0x13e0 mm/slub.c:3540
__slab_alloc mm/slub.c:3625 [inline]
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]
kmalloc_trace+0x267/0x360 mm/slub.c:4007
kmalloc include/linux/slab.h:590 [inline]
kzalloc include/linux/slab.h:711 [inline]
kernfs_get_open_node fs/kernfs/file.c:523 [inline]
kernfs_fop_open+0x803/0xcd0 fs/kernfs/file.c:691
do_dentry_open+0x907/0x15a0 fs/open.c:956
do_open fs/namei.c:3643 [inline]
path_openat+0x2860/0x3240 fs/namei.c:3800
do_filp_open+0x235/0x490 fs/namei.c:3827
do_sys_openat2+0x13e/0x1d0 fs/open.c:1407
do_sys_open fs/open.c:1422 [inline]
__do_sys_openat fs/open.c:1438 [inline]
__se_sys_openat fs/open.c:1433 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1433
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
page last free pid 4526 tgid 4526 stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1140 [inline]
free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346
free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486
rcu_do_batch kernel/rcu/tree.c:2196 [inline]
rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2471
__do_softirq+0x2bc/0x943 kernel/softirq.c:554

Memory state around the buggy address:
ffff8880290d9800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880290d9880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880290d9900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880290d9980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880290d9a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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