From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4AFE949624 for ; Sun, 11 Aug 2024 12:15:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723378505; cv=none; b=dKS90pKQpIj7V6iPwbqJ+yNoVjh8dfQwNHafdJbswgcbAfvxQMvLK+syth6agnxzxPBbpplKIm6n/sZgB9hSjl8FgXQSXLjWdjyQcNTTUR7P4wjUpK6Z0ZUjtxx6UHtiGzz9OggBCsdTuaaq4HyXu+dDqFygywwpYLAY/VyQU1s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723378505; c=relaxed/simple; bh=GkLJpc+0i+DVMIuOPA8SihH/mNpv+k5txw0GFeKA7vA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hNli8ZtbtVDXqAN7RTLYxAGCFSXoZ4gS/Epa3mICKfCWKiQDZdm92ACxRWQrKOuEJ9AKbiNGMPSv7PfcW7lZq907L/DlxwCSwvb6s/9PVIWFfVXyjbUuPtN7k280ciPt+6+Rn1/8RSCPN2dVLgDWySyHAEJkzlWJ8EEWjT7fwsc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=eErJFGgh; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="eErJFGgh" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1723378502; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=vJWtfXhpmbP9dVLRtODwEu3Qix1yo/UdcPO4PLEFssQ=; b=eErJFGghDZMWuavkepnOFVdzJ3hu73d7x6wv4MD0GdXkO1sXkkKFmEnsvEd9ed28CagZat /KwE3IozmQBelh4kHo4MsRoCWollRK9VvtvGpvSbLmJmTfe8UnhypjS6qIwF/NgwADWAiC dUvUFShJnCfFN5sA7r2vK3COJUZhB7c= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-160-h_zFFy98M3Sbb8BKznxz4g-1; Sun, 11 Aug 2024 08:14:58 -0400 X-MC-Unique: h_zFFy98M3Sbb8BKznxz4g-1 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BAA651944F05; Sun, 11 Aug 2024 12:14:55 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.224.19]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id 015281955F3C; Sun, 11 Aug 2024 12:14:48 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Sun, 11 Aug 2024 14:14:52 +0200 (CEST) Date: Sun, 11 Aug 2024 14:14:45 +0200 From: Oleg Nesterov To: syzbot , Andrii Nakryiko , jolsa@kernel.org Cc: acme@kernel.org, adrian.hunter@intel.com, alexander.shishkin@linux.intel.com, irogers@google.com, kan.liang@linux.intel.com, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-trace-kernel@vger.kernel.org, mark.rutland@arm.com, mhiramat@kernel.org, mingo@redhat.com, namhyung@kernel.org, peterz@infradead.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [perf?] KASAN: slab-use-after-free Read in __uprobe_unregister Message-ID: <20240811121444.GA30068@redhat.com> References: <000000000000382d39061f59f2dd@google.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <000000000000382d39061f59f2dd@google.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Hmm, bpf_uprobe_multi_link_attach() looks obviously wrong. bpf_link_prime() is called after the for (i = 0; i < cnt; i++) { uprobe_register(...); ... } loop. If bpf_link_prime() fails, bpf_uprobe_multi_link_attach() just do kvfree(uprobes) without _unregister(). In particular, this leaks the freed bpf_uprobe->consumer in the uprobe->consumers list. After that another _unregister() on the same uprobe can hit the problem. I guess we need a simple patch for -stable... Oleg. On 08/10, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 6a0e38264012 Merge tag 'for-6.11-rc2-tag' of git://git.ker.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=13d4fc91980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=505ed4a1dd93463a > dashboard link: https://syzkaller.appspot.com/bug?extid=f7a1c2c2711e4a780f19 > compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15fd9755980000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1546c4e5980000 > > Downloadable assets: > disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-6a0e3826.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/dd9ba9302e4d/vmlinux-6a0e3826.xz > kernel image: https://storage.googleapis.com/syzbot-assets/aa3ef19fbf4e/bzImage-6a0e3826.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+f7a1c2c2711e4a780f19@syzkaller.appspotmail.com > > R10: 0000000000000001 R11: 0000000000000246 R12: 00007f4aa48c4618 > R13: 00007ffc0345d258 R14: 0000000000000001 R15: 0000000000000001 > > ================================================================== > BUG: KASAN: slab-use-after-free in consumer_del kernel/events/uprobes.c:772 [inline] > BUG: KASAN: slab-use-after-free in __uprobe_unregister+0x210/0x260 kernel/events/uprobes.c:1087 > Read of size 8 at addr ffff888025a498b8 by task syz-executor380/5333 > > CPU: 2 UID: 0 PID: 5333 Comm: syz-executor380 Not tainted 6.11.0-rc2-syzkaller-00027-g6a0e38264012 #0 > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 > Call Trace: > > __dump_stack lib/dump_stack.c:93 [inline] > dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 > print_address_description mm/kasan/report.c:377 [inline] > print_report+0xc3/0x620 mm/kasan/report.c:488 > kasan_report+0xd9/0x110 mm/kasan/report.c:601 > consumer_del kernel/events/uprobes.c:772 [inline] > __uprobe_unregister+0x210/0x260 kernel/events/uprobes.c:1087 > uprobe_unregister+0x45/0x70 kernel/events/uprobes.c:1111 > bpf_uprobe_unregister+0xfb/0x1d0 kernel/trace/bpf_trace.c:3187 > bpf_uprobe_multi_link_release+0x6d/0x180 kernel/trace/bpf_trace.c:3197 > bpf_link_free+0x12c/0x2b0 kernel/bpf/syscall.c:3067 > bpf_link_put_direct kernel/bpf/syscall.c:3107 [inline] > bpf_link_release+0x63/0x80 kernel/bpf/syscall.c:3114 > __fput+0x408/0xbb0 fs/file_table.c:422 > task_work_run+0x14e/0x250 kernel/task_work.c:228 > exit_task_work include/linux/task_work.h:40 [inline] > do_exit+0xaa3/0x2bb0 kernel/exit.c:882 > do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 > __do_sys_exit_group kernel/exit.c:1042 [inline] > __se_sys_exit_group kernel/exit.c:1040 [inline] > __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1040 > x64_sys_call+0x14a9/0x16a0 arch/x86/include/generated/asm/syscalls_64.h:232 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7f4aa48570e9 > Code: Unable to access opcode bytes at 0x7f4aa48570bf. > RSP: 002b:00007ffc0345d048 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4aa48570e9 > RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 > RBP: 00007f4aa48ca350 R08: ffffffffffffffb8 R09: 00007f4aa48c0038 > R10: 0000000000000001 R11: 0000000000000246 R12: 00007f4aa48ca350 > R13: 0000000000000000 R14: 00007f4aa48cada0 R15: 00007f4aa48211a0 > > > Allocated by task 5333: > kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 > kasan_save_track+0x14/0x30 mm/kasan/common.c:68 > poison_kmalloc_redzone mm/kasan/common.c:370 [inline] > __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387 > kasan_kmalloc include/linux/kasan.h:211 [inline] > __do_kmalloc_node mm/slub.c:4158 [inline] > __kmalloc_node_noprof+0x211/0x430 mm/slub.c:4164 > __kvmalloc_node_noprof+0x9d/0x1a0 mm/util.c:650 > kvmalloc_array_node_noprof include/linux/slab.h:833 [inline] > bpf_uprobe_multi_link_attach+0x45d/0xe20 kernel/trace/bpf_trace.c:3439 > link_create kernel/bpf/syscall.c:5319 [inline] > __sys_bpf+0x41ff/0x4a20 kernel/bpf/syscall.c:5780 > __do_sys_bpf kernel/bpf/syscall.c:5817 [inline] > __se_sys_bpf kernel/bpf/syscall.c:5815 [inline] > __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5815 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > Freed by task 5333: > kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 > kasan_save_track+0x14/0x30 mm/kasan/common.c:68 > kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 > poison_slab_object+0xf7/0x160 mm/kasan/common.c:240 > __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256 > kasan_slab_free include/linux/kasan.h:184 [inline] > slab_free_hook mm/slub.c:2252 [inline] > slab_free mm/slub.c:4473 [inline] > kfree+0x12a/0x3b0 mm/slub.c:4594 > kvfree+0x47/0x50 mm/util.c:696 > bpf_uprobe_multi_link_attach+0xaae/0xe20 kernel/trace/bpf_trace.c:3500 > link_create kernel/bpf/syscall.c:5319 [inline] > __sys_bpf+0x41ff/0x4a20 kernel/bpf/syscall.c:5780 > __do_sys_bpf kernel/bpf/syscall.c:5817 [inline] > __se_sys_bpf kernel/bpf/syscall.c:5815 [inline] > __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5815 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > The buggy address belongs to the object at ffff888025a49880 > which belongs to the cache kmalloc-64 of size 64 > The buggy address is located 56 bytes inside of > freed 64-byte region [ffff888025a49880, ffff888025a498c0) > > The buggy address belongs to the physical page: > page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25a49 > flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) > page_type: 0xfdffffff(slab) > raw: 00fff00000000000 ffff8880158428c0 dead000000000100 dead000000000122 > raw: 0000000000000000 0000000080200020 00000001fdffffff 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 11, tgid 11 (kworker/u32:0), ts 16060739565, free_ts 16025939467 > set_page_owner include/linux/page_owner.h:32 [inline] > post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1493 > prep_new_page mm/page_alloc.c:1501 [inline] > get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3442 > __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4700 > __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] > alloc_pages_node_noprof include/linux/gfp.h:296 [inline] > alloc_slab_page+0x4e/0xf0 mm/slub.c:2321 > allocate_slab mm/slub.c:2484 [inline] > new_slab+0x84/0x260 mm/slub.c:2537 > ___slab_alloc+0xdac/0x1870 mm/slub.c:3723 > __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3813 > __slab_alloc_node mm/slub.c:3866 [inline] > slab_alloc_node mm/slub.c:4025 [inline] > __kmalloc_cache_node_noprof+0xf1/0x350 mm/slub.c:4197 > kmalloc_node_noprof include/linux/slab.h:704 [inline] > __get_vm_area_node+0xe1/0x2d0 mm/vmalloc.c:3109 > __vmalloc_node_range_noprof+0x276/0x1520 mm/vmalloc.c:3801 > alloc_thread_stack_node kernel/fork.c:313 [inline] > dup_task_struct kernel/fork.c:1113 [inline] > copy_process+0x2f3b/0x8de0 kernel/fork.c:2204 > kernel_clone+0xfd/0x980 kernel/fork.c:2781 > user_mode_thread+0xb4/0xf0 kernel/fork.c:2859 > call_usermodehelper_exec_work kernel/umh.c:172 [inline] > call_usermodehelper_exec_work+0xcb/0x170 kernel/umh.c:158 > process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 > process_scheduled_works kernel/workqueue.c:3312 [inline] > worker_thread+0x6c8/0xf20 kernel/workqueue.c:3390 > page last free pid 986 tgid 986 stack trace: > reset_page_owner include/linux/page_owner.h:25 [inline] > free_pages_prepare mm/page_alloc.c:1094 [inline] > free_unref_page+0x64a/0xe40 mm/page_alloc.c:2612 > vfree+0x181/0x7a0 mm/vmalloc.c:3364 > delayed_vfree_work+0x56/0x70 mm/vmalloc.c:3285 > process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 > process_scheduled_works kernel/workqueue.c:3312 [inline] > worker_thread+0x6c8/0xf20 kernel/workqueue.c:3390 > kthread+0x2c1/0x3a0 kernel/kthread.c:389 > ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > Memory state around the buggy address: > ffff888025a49780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc > ffff888025a49800: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc > >ffff888025a49880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc > ^ > ffff888025a49900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc > ffff888025a49980: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc > ================================================================== > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup >