From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f199.google.com (mail-oi1-f199.google.com [209.85.167.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8789F379C5F for ; Sun, 4 Oct 2026 01:06:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791075991; cv=none; b=dSkD6s71LE05uf6B7zjtlx95kMMP78EJWDSvyOxLeHdcIWJdfYchArg32wv9Uspqx0f3toygUqf4q9CAGWQ0t8PP9l4NRH/+KE8aEcSMpn5nYOtrlRrNX6+hMKDbK0PebFwyM4klvCTx4Je305OrJj6WqlfT+c4Gjf13rbDc5rA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791075991; c=relaxed/simple; bh=DBPueCII86TubAWeqKo024OoAQSv4qhFHq0xFTq6bBA=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=BY0Hw8/tSTT8TmPrPitHfuJkKzlI/Hkk/ZQ1VGcsZ7xQFDE0e1QRytj71L6HKGDjTlz3PbSSco5bx3um8xpw9bVVIy5Raf0q/SarqRODmGhtv6POx5I9XHt+PR237/68WNg8BKdeoTQypbV2ahsiytoQxyAczjVbajD0efo0JxM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.167.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oi1-f199.google.com with SMTP id 5614622812f47-4b1bc2e44e0so1183855b6e.0 for ; Sat, 03 Oct 2026 18:06:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791075988; x=1791680788; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=LtlDrk5XM1TNe6UhnllojCm0xyW0vuqat3D05iyMhkw=; b=eoDcWD/5/BBo0444qPYSMLquaaCW+VIaRCjogQ6h0oVh+BObUFgARxmXhsZYhxGUaq BE9ZFWcH9am+jGOjF1z5PAIcZZ+65cnquVPyx/A26NtwGdcei6C2/MaVkSYLNlch4Ogk uSQ4qwdT9ZagW9vlPq0ytK4k8cztwXPbAn70P3z4nE4hF2uDMjZpfp08gjOHwl5JY7Nr uylA4+i/HvatrRvLhUYUNeccFS5AxDzVrdyg83G+B4ftIIX4cTVAvA4BQXWyIDBdVwq1 WZhPhrXKoEiP4taqRbNqecl/NXUOeKC+gmxnW4sOa4WeJJLzVItPtxpLatapKCj1vBG1 skTg== X-Forwarded-Encrypted: i=1; AKwUvBwO/B7yZpMbMNvBWj1e80wTVXO7TcPlUFlrJVCJ4n/LYT6WafKARsepiAedZ0rTNGI3Ai6YmKipZq7Tb8w=@vger.kernel.org X-Gm-Message-State: AFuF++kmT1ZL97zO5rcJKIKR4iKahx+oaG15w+FOutSijgJI4vGBZBql A71c135TfcEDp3qiRwUi3/vGS8ceSnTrV5po5P9FaelIdU4WpKP/Z1XiOYb+Qr0wEZUe9ZENWpt yNWmfR5xhpRKDGZ6OHb3Akouu2B2FrzrwabzvXpkhlOigIVyAJiZvyJsezVQ= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:1813:b0:4b2:8d7b:41b8 with SMTP id 5614622812f47-4f529202310mr7161890b6e.18.1791075988605; Sat, 03 Oct 2026 18:06:28 -0700 (PDT) Date: Sat, 03 Oct 2026 18:06:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6ac1a694.01314a6c.556a8.0002.GAE@google.com> Subject: [syzbot] [rdma?] KASAN: slab-use-after-free Read in debug_mutex_unlock From: syzbot To: jgg@ziepe.ca, leon@kernel.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 48a5a7ab8d6a Merge tag 'v7.2-rc4-smb3-client-fixes' of git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=166922a9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=f221a1b5d497ed15 dashboard link: https://syzkaller.appspot.com/bug?extid=ae549381b4daac2895b1 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-48a5a7ab.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f512830db6a9/vmlinux-48a5a7ab.xz kernel image: https://storage.googleapis.com/syzbot-assets/13bb0e168566/bzImage-48a5a7ab.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ae549381b4daac2895b1@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in debug_mutex_unlock+0x124/0x140 kernel/locking/mutex-debug.c:74 Read of size 8 at addr ffff888024e65418 by task kworker/u33:9/1164 CPU: 1 UID: 0 PID: 1164 Comm: kworker/u33:9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: ib_addr process_one_req Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 debug_mutex_unlock+0x124/0x140 kernel/locking/mutex-debug.c:74 __mutex_unlock_slowpath+0x195/0x930 kernel/locking/mutex.c:1031 addr_handler+0x12d/0x4d0 drivers/infiniband/core/cma.c:3555 process_one_req+0x127/0x680 drivers/infiniband/core/addr.c:624 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 9271: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2e5/0x6c0 mm/slub.c:5515 _kmalloc_noprof include/linux/slab.h:969 [inline] _kzalloc_noprof include/linux/slab.h:1290 [inline] __rdma_create_id+0x5b/0x8f0 drivers/infiniband/core/cma.c:1016 rdma_create_user_id+0x7d/0xe0 drivers/infiniband/core/cma.c:1074 ucma_create_id+0x189/0x380 drivers/infiniband/core/ucma.c:470 ucma_write+0x1fb/0x330 drivers/infiniband/core/ucma.c:1856 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x1f8/0x250 fs/read_write.c:739 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 9270: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2705 [inline] slab_free mm/slub.c:6405 [inline] kfree+0x22b/0x6c0 mm/slub.c:6720 ucma_close_id drivers/infiniband/core/ucma.c:188 [inline] ucma_destroy_private_ctx+0xb30/0xe90 drivers/infiniband/core/ucma.c:585 ucma_close+0x1aa/0x240 drivers/infiniband/core/ucma.c:1921 __fput+0x3ff/0xb50 fs/file_table.c:512 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:70 [inline] exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] __do_fast_syscall_32+0x701/0x970 arch/x86/entry/syscall_32.c:310 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff888024e65000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1048 bytes inside of freed 2048-byte region [ffff888024e65000, ffff888024e65800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x24e60 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801bc42f00 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801bc42f00 dead000000000100 dead000000000122 head: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 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 5143, tgid 5143 (klogd), ts 50831000983, free_ts 47183968045 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3294 [inline] allocate_slab mm/slub.c:3408 [inline] new_slab+0xa2/0x650 mm/slub.c:3454 refill_objects+0xe3/0x410 mm/slub.c:7338 refill_sheaf mm/slub.c:2832 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4703 alloc_from_pcs mm/slub.c:4801 [inline] slab_alloc_node mm/slub.c:4933 [inline] __kmalloc_cache_noprof+0x479/0x6c0 mm/slub.c:5511 _kmalloc_noprof include/linux/slab.h:969 [inline] syslog_print+0xf8/0x620 kernel/printk/printk.c:1585 do_syslog+0x5bd/0x6d0 kernel/printk/printk.c:1763 __do_sys_syslog kernel/printk/printk.c:1855 [inline] __se_sys_syslog kernel/printk/printk.c:1853 [inline] __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1853 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5656 tgid 5656 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 __folio_put+0x3b4/0x5f0 mm/swap.c:112 folio_put include/linux/mm.h:2124 [inline] put_page include/linux/mm.h:2193 [inline] put_netmem include/net/netmem.h:394 [inline] skb_page_unref include/linux/skbuff_ref.h:43 [inline] __skb_frag_unref include/linux/skbuff_ref.h:56 [inline] skb_release_data+0x649/0x8e0 net/core/skbuff.c:1110 skb_release_all net/core/skbuff.c:1191 [inline] __napi_kfree_skb net/core/skbuff.c:1485 [inline] kfree_skb_napi_cache net/core/skbuff.c:7286 [inline] skb_attempt_defer_free+0x2ed/0x830 net/core/skbuff.c:7319 tcp_eat_recv_skb net/ipv4/tcp.c:1621 [inline] tcp_recvmsg_locked+0x11ed/0x2a30 net/ipv4/tcp.c:2899 tcp_recvmsg+0x141/0x630 net/ipv4/tcp.c:2944 inet_recvmsg+0xd5/0x4c0 net/ipv4/af_inet.c:894 sock_recvmsg_nosec net/socket.c:1126 [inline] sock_recvmsg+0x1b8/0x220 net/socket.c:1148 sock_read_iter+0x2b0/0x3a0 net/socket.c:1217 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x960/0xb40 fs/read_write.c:574 ksys_read+0x1f8/0x250 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888024e65300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024e65380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888024e65400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888024e65480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024e65500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. 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