From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f197.google.com (mail-il1-f197.google.com [209.85.166.197]) (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 1596D19DF8B for ; Sat, 28 Sep 2024 07:43:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727509410; cv=none; b=o6ZyAWn8aV3PUJwuaTbypAu91B2i5una4xyiuiqNJ4RLo72HK9+RodbbHb7MM/x6843waKi5SCkboiIHbsCOM6S2f+rvSDOn61sfA0vgd4ELx3ZEJ6rW8EeM+1M+TnEASM+3U1iO/b8qeIlDuSUGAJkMfLgQo1J/+RvcF5UiLXw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727509410; c=relaxed/simple; bh=fk9gG4gQalEMc0N1bhMZCxxE0ByNLA57AB45kz8KLdc=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=lmGcYEYd9DpoRX4QBN2n9BMp/tvGscDS/7UIH4aPFGUlJHYbr9BCzT7UmsgIt37YQOX7dJFAre58I57sG8n+sSO59FGcN+0z3G7+eSW87Dhe5sUUWkPjJ1krlIxbL8ey5BVVJi5n/HVdznKHwA1wr2R3eRmnEqyxJIq/JFW4Meo= 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=209.85.166.197 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-il1-f197.google.com with SMTP id e9e14a558f8ab-3a3479460f4so15762145ab.2 for ; Sat, 28 Sep 2024 00:43:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1727509408; x=1728114208; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=HtGmfFQ4rTZm4/FqmOVqkSPdMe1H411qdUEqUKengqw=; b=BJa2jsOHMI3io7yjWxxg/Iw4ezldXriv3eO5W/ljlgOK3Cef5BJ6wW6T0hynwTg3xy vEaby+5eJ6wNEMr8DzF57OKunln1wf2hhfHlBae76GYvESQ3xjcdhXXTaf45ltYBPCpP Ki+dF4clwPN4/P2eIU9NYhP+F3Kx2kS6Y5aSWLXEGlQ1+wTryYrAFBMAPuKI0EQtEleM ZyujLsqZMzaMzghhSnMbMQD5iSi0Vzvi7v+IH5qhqxxoZGgjLQGD55WO5+i4d1R3pYKM 7RkrHiAFHaQeWB7bGUySPBRotQWUzNV9dnkGvUaMvnLLn1K9ggSf+7yDUYTBYDFqaKAy hX4w== X-Forwarded-Encrypted: i=1; AJvYcCVY8x097t0CIJV0uOsGBBeRZHb5zXqFPY0664hd0AGvCwYXzJry66R18ZiC3mWrSp3wXfbj4Nf0MLS940Y=@vger.kernel.org X-Gm-Message-State: AOJu0YzP2/eBVhH/zH+LQiJeFbs86IXy3KieIJ2b0p8tq1gfYi1DZ/l0 dolpYvY/ZEIwqZhQLuDjAbK3AfdreQLjuWBUDzMigSxAtOPRjbZAfPiw3Vu4jnrFr0yRwksMSBb t4c/4/7+ZfAoBMVRzHRmB+hyYyvOScr4Nd3N5uN4Mup5SLH9F6qceWIY= X-Google-Smtp-Source: AGHT+IFcWue9Y2GaKT1PfcYdcnRS4BLO1UvY+S4vT1eBKqjRYvcV2dDYezsfqK+slYAThKXzQ+pbb+6BXCHzQYhgnGTxiu8fKW9H Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a92:ca4c:0:b0:3a3:449b:5989 with SMTP id e9e14a558f8ab-3a3452ba439mr49601785ab.21.1727509408212; Sat, 28 Sep 2024 00:43:28 -0700 (PDT) Date: Sat, 28 Sep 2024 00:43:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <66f7b3a0.050a0220.46d20.0038.GAE@google.com> Subject: [syzbot] [mm?] possible deadlock in shmem_file_write_iter From: syzbot To: akpm@linux-foundation.org, hughd@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: e477dba5442c Merge tag 'for-6.12/dm-changes' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=102ade27980000 kernel config: https://syzkaller.appspot.com/x/.config?x=b2d4fdf18a83ec0b dashboard link: https://syzkaller.appspot.com/bug?extid=288aa6838b3263f52e7e 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/be1e82b0133d/disk-e477dba5.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/8d9e4b1a6733/vmlinux-e477dba5.xz kernel image: https://storage.googleapis.com/syzbot-assets/b79025eddfb1/bzImage-e477dba5.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+288aa6838b3263f52e7e@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.11.0-syzkaller-11624-ge477dba5442c #0 Not tainted ------------------------------------------------------ syz.2.1702/9983 is trying to acquire lock: ffff888028091e18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:153 but task is already holding lock: ffff888077ef3708 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] ffff888077ef3708 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: shmem_file_write_iter+0x80/0x120 mm/shmem.c:3211 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_write+0x99/0x220 kernel/locking/rwsem.c:1579 inode_lock include/linux/fs.h:815 [inline] process_measurement+0x439/0x1fb0 security/integrity/ima/ima_main.c:250 ima_file_mmap+0x13d/0x2b0 security/integrity/ima/ima_main.c:455 security_mmap_file+0x7e7/0xa40 security/security.c:2977 __do_sys_remap_file_pages mm/mmap.c:1692 [inline] __se_sys_remap_file_pages+0x6e6/0xa50 mm/mmap.c:1624 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&mm->mmap_lock){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3158 [inline] check_prevs_add kernel/locking/lockdep.c:3277 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_read_killable+0xca/0xd30 kernel/locking/rwsem.c:1549 mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:153 get_mmap_lock_carefully mm/memory.c:6108 [inline] lock_mm_and_find_vma+0x29c/0x2f0 mm/memory.c:6159 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 fault_in_readable+0x165/0x2b0 fault_in_iov_iter_readable+0x229/0x280 lib/iov_iter.c:94 generic_perform_write+0x259/0x6d0 mm/filemap.c:4040 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3221 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6f/0xc90 fs/read_write.c:683 ksys_write+0x183/0x2b0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#12); lock(&mm->mmap_lock); lock(&sb->s_type->i_mutex_key#12); rlock(&mm->mmap_lock); *** DEADLOCK *** 3 locks held by syz.2.1702/9983: #0: ffff888054784478 (&f->f_pos_lock){+.+.}-{3:3}, at: fdget_pos+0x24e/0x320 fs/file.c:1187 #1: ffff88814a584420 (sb_writers#5){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #1: ffff88814a584420 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 #2: ffff888077ef3708 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #2: ffff888077ef3708 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: shmem_file_write_iter+0x80/0x120 mm/shmem.c:3211 stack backtrace: CPU: 1 UID: 0 PID: 9983 Comm: syz.2.1702 Not tainted 6.11.0-syzkaller-11624-ge477dba5442c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2203 check_prev_add kernel/locking/lockdep.c:3158 [inline] check_prevs_add kernel/locking/lockdep.c:3277 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_read_killable+0xca/0xd30 kernel/locking/rwsem.c:1549 mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:153 get_mmap_lock_carefully mm/memory.c:6108 [inline] lock_mm_and_find_vma+0x29c/0x2f0 mm/memory.c:6159 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:fault_in_readable+0x165/0x2b0 mm/gup.c:2235 Code: b3 ff 4c 8d b3 ff 0f 00 00 48 89 d8 4d 01 e6 49 81 e6 00 f0 ff ff 49 39 c6 72 6b e8 f5 c8 b3 ff 4c 39 f3 74 6e 4c 89 64 24 10 <44> 8a 23 43 0f b6 04 2f 84 c0 75 18 44 88 64 24 40 48 81 c3 00 10 RSP: 0018:ffffc900045c7a40 EFLAGS: 00050283 RAX: ffffffff81e0eba7 RBX: 00000000201e1000 RCX: 0000000000040000 RDX: ffffc9001ddf8000 RSI: 000000000000bffd RDI: 000000000000bffe RBP: ffffc900045c7af8 R08: ffffffff81e0eb18 R09: ffffffff84b912a9 R10: 0000000000000002 R11: ffff888025213c00 R12: 0000000000200000 R13: dffffc0000000000 R14: 0000000020201000 R15: 1ffff920008b8f50 fault_in_iov_iter_readable+0x229/0x280 lib/iov_iter.c:94 generic_perform_write+0x259/0x6d0 mm/filemap.c:4040 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3221 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6f/0xc90 fs/read_write.c:683 ksys_write+0x183/0x2b0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbca257df39 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbca3459038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fbca2735f80 RCX: 00007fbca257df39 RDX: 000000000208e24b RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007fbca25f0216 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbca2735f80 R15: 00007ffd5bf037c8 ---------------- Code disassembly (best guess): 0: b3 ff mov $0xff,%bl 2: 4c 8d b3 ff 0f 00 00 lea 0xfff(%rbx),%r14 9: 48 89 d8 mov %rbx,%rax c: 4d 01 e6 add %r12,%r14 f: 49 81 e6 00 f0 ff ff and $0xfffffffffffff000,%r14 16: 49 39 c6 cmp %rax,%r14 19: 72 6b jb 0x86 1b: e8 f5 c8 b3 ff call 0xffb3c915 20: 4c 39 f3 cmp %r14,%rbx 23: 74 6e je 0x93 25: 4c 89 64 24 10 mov %r12,0x10(%rsp) * 2a: 44 8a 23 mov (%rbx),%r12b <-- trapping instruction 2d: 43 0f b6 04 2f movzbl (%r15,%r13,1),%eax 32: 84 c0 test %al,%al 34: 75 18 jne 0x4e 36: 44 88 64 24 40 mov %r12b,0x40(%rsp) 3b: 48 rex.W 3c: 81 .byte 0x81 3d: c3 ret 3e: 00 10 add %dl,(%rax) --- This report is generated by a bot. 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