From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [117.135.210.2]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1F5EB1DFCB; Sun, 22 Sep 2024 05:46:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=117.135.210.2 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726984022; cv=none; b=secUcqmbJsVGUbPfvGTJrNsXKxCeKow3bQELSPvr/wY//GvoWnFqS0sO49cQvCa413aFBIVPHlI7bVWDXECIS+oNNtO4PdmlZyBuJC9xBlNo03F/zF0SKZw1BrQAGA8UOxlNNEzhSsUwSX7gXOBUGk9IEFN40imG/i1KqpGcvos= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726984022; c=relaxed/simple; bh=8nr/cLUXFopPhAFql75WeQ4EN2Wa5X690MlP5oLQ6/E=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lAVfwqVdMZoua8mqkNCHVx0Oe4mw2ufWlCKPxcWjKoIYQ3S8zxzZ9Iv8hV2UuFX32z3V+T72NMjMWWZpXoPBhLyYbfhsugLbLsGQD6q2YUgW5zvABDENY+DctvpmU7yrUL7KCfYEnEdJjCaJU1QCJI6o3uj4aw64nS0fY6wZkts= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=eXvMQYVY; arc=none smtp.client-ip=117.135.210.2 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="eXvMQYVY" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=Date:From:Subject:Message-ID:MIME-Version: Content-Type; bh=isa+ilqZGLFW5BB7FM6u6Y5eiCAALL0Gb9yQF1cCasY=; b=eXvMQYVYmq/ICtdt4Gl3PC6jZbxbENc9/Co+mTNjrZwMzt0EjT6Tu8YtJzWsX4 GUtVOZXfhcxwDYf/6jKEWBQfeeSDK+rXjN057pUzBG3upS0OAEYbmL4VzwsGpWtz Dd02LDQTV4xNRFLJGELu4q+EvUsghrje5oV99rYGLQhEs= Received: from localhost (unknown [36.33.37.137]) by gzga-smtp-mta-g3-5 (Coremail) with SMTP id _____wBHxJ4jr+9mFpEGOQ--.32791S2; Sun, 22 Sep 2024 13:46:11 +0800 (CST) Date: Sun, 22 Sep 2024 13:46:11 +0800 From: Qianqiang Liu To: syzbot Cc: adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tytso@mit.edu Subject: Re: [syzbot] [ext4?] KASAN: out-of-bounds Read in ext4_xattr_set_entry Message-ID: References: <66ef61d6.050a0220.3195df.0072.GAE@google.com> Precedence: bulk X-Mailing-List: linux-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: <66ef61d6.050a0220.3195df.0072.GAE@google.com> X-CM-TRANSID:_____wBHxJ4jr+9mFpEGOQ--.32791S2 X-Coremail-Antispam: 1Uf129KBjvAXoW3tryxXw4rWr1xKry7AFW5Wrg_yoW8Jr17Wo ZFqr15CF48Ga45JFs5Ar4UtryUGFy8ZFsrJr1rur45GF9xZr1DCr13K3yYyr18tr45GF13 Zr17tw1rW3yDXFn5n29KB7ZKAUJUUUU8529EdanIXcx71UUUUU7v73VFW2AGmfu7bjvjm3 AaLaJ3UbIYCTnIWIevJa73UjIFyTuYvjxUcasUDUUUU X-CM-SenderInfo: xtld01pldqwhxolxqiywtou0bp/1tbiRQNiambveN68GAABsE On Sat, Sep 21, 2024 at 05:16:22PM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: a940d9a43e62 Merge tag 'soc-arm-6.12' of git://git.kernel... > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=16689207980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=1653f803fffa3848 > dashboard link: https://syzkaller.appspot.com/bug?extid=f792df426ff0f5ceb8d1 > 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=11689207980000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=104d469f980000 > > Downloadable assets: > disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-a940d9a4.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/371e11b6a9e5/vmlinux-a940d9a4.xz > kernel image: https://storage.googleapis.com/syzbot-assets/920eb0c53785/bzImage-a940d9a4.xz > mounted in repro: https://storage.googleapis.com/syzbot-assets/4146c0b2e744/mount_0.gz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+f792df426ff0f5ceb8d1@syzkaller.appspotmail.com > > EXT4-fs (loop0): 1 truncate cleaned up > EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. > ================================================================== > BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x8ce/0x1f60 fs/ext4/xattr.c:1781 > Read of size 18446744073709551572 at addr ffff888036426850 by task syz-executor264/5095 > > CPU: 0 UID: 0 PID: 5095 Comm: syz-executor264 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #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+0x241/0x360 lib/dump_stack.c:119 > 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 > kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 > __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94 > ext4_xattr_set_entry+0x8ce/0x1f60 fs/ext4/xattr.c:1781 > ext4_xattr_block_set+0xa39/0x3980 fs/ext4/xattr.c:2028 > ext4_xattr_move_to_block fs/ext4/xattr.c:2669 [inline] > ext4_xattr_make_inode_space fs/ext4/xattr.c:2744 [inline] > ext4_expand_extra_isize_ea+0x12d7/0x1cf0 fs/ext4/xattr.c:2836 > __ext4_expand_extra_isize+0x2fb/0x3e0 fs/ext4/inode.c:5858 > ext4_try_to_expand_extra_isize fs/ext4/inode.c:5901 [inline] > __ext4_mark_inode_dirty+0x524/0x880 fs/ext4/inode.c:5979 > __ext4_unlink+0x6c2/0xb50 fs/ext4/namei.c:3289 > ext4_unlink+0x1bf/0x5a0 fs/ext4/namei.c:3318 > vfs_unlink+0x365/0x650 fs/namei.c:4469 > do_unlinkat+0x4ae/0x830 fs/namei.c:4533 > __do_sys_unlink fs/namei.c:4581 [inline] > __se_sys_unlink fs/namei.c:4579 [inline] > __x64_sys_unlink+0x47/0x50 fs/namei.c:4579 > 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: 0033:0x7f2549cabe99 > Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007fff914df8a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 > RAX: ffffffffffffffda RBX: 0031656c69662f2e RCX: 00007f2549cabe99 > RDX: 00007f2549cabe99 RSI: 00007f2549cabe99 RDI: 0000000020000180 > RBP: 0032656c69662f2e R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff914df8e0 > R13: 00007fff914dfb08 R14: 431bde82d7b634db R15: 00007f2549cf503b > > > Allocated by task 5095: > 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] > __do_kmalloc_node mm/slub.c:4159 [inline] > __kmalloc_node_track_caller_noprof+0x225/0x440 mm/slub.c:4178 > kmemdup_noprof+0x2a/0x60 mm/util.c:133 > ext4_xattr_block_set+0x88b/0x3980 fs/ext4/xattr.c:1976 > ext4_xattr_move_to_block fs/ext4/xattr.c:2669 [inline] > ext4_xattr_make_inode_space fs/ext4/xattr.c:2744 [inline] > ext4_expand_extra_isize_ea+0x12d7/0x1cf0 fs/ext4/xattr.c:2836 > __ext4_expand_extra_isize+0x2fb/0x3e0 fs/ext4/inode.c:5858 > ext4_try_to_expand_extra_isize fs/ext4/inode.c:5901 [inline] > __ext4_mark_inode_dirty+0x524/0x880 fs/ext4/inode.c:5979 > __ext4_unlink+0x6c2/0xb50 fs/ext4/namei.c:3289 > ext4_unlink+0x1bf/0x5a0 fs/ext4/namei.c:3318 > vfs_unlink+0x365/0x650 fs/namei.c:4469 > do_unlinkat+0x4ae/0x830 fs/namei.c:4533 > __do_sys_unlink fs/namei.c:4581 [inline] > __se_sys_unlink fs/namei.c:4579 [inline] > __x64_sys_unlink+0x47/0x50 fs/namei.c:4579 > 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 > > The buggy address belongs to the object at ffff888036426800 > which belongs to the cache kmalloc-1k of size 1024 > The buggy address is located 80 bytes inside of > 1024-byte region [ffff888036426800, ffff888036426c00) > > The buggy address belongs to the physical page: > page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x36424 > head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 > flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) > page_type: 0xfdffffff(slab) > raw: 04fff00000000040 ffff88801ac41dc0 dead000000000100 dead000000000122 > raw: 0000000000000000 0000000080080008 00000001fdffffff 0000000000000000 > head: 04fff00000000040 ffff88801ac41dc0 dead000000000100 dead000000000122 > head: 0000000000000000 0000000080080008 00000001fdffffff 0000000000000000 > head: 04fff00000000002 ffffea0000d90901 ffffffffffffffff 0000000000000000 > head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > page_owner tracks the page as allocated > page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5049, tgid 5049 (dhcpcd), ts 74832155643, free_ts 73695396465 > set_page_owner include/linux/page_owner.h:32 [inline] > post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1500 > prep_new_page mm/page_alloc.c:1508 [inline] > get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3446 > __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4702 > __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] > alloc_pages_node_noprof include/linux/gfp.h:296 [inline] > alloc_slab_page+0x5f/0x120 mm/slub.c:2319 > allocate_slab+0x5a/0x2f0 mm/slub.c:2482 > new_slab mm/slub.c:2535 [inline] > ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3721 > __slab_alloc+0x58/0xa0 mm/slub.c:3811 > __slab_alloc_node mm/slub.c:3864 [inline] > slab_alloc_node mm/slub.c:4026 [inline] > __do_kmalloc_node mm/slub.c:4158 [inline] > __kmalloc_noprof+0x25a/0x400 mm/slub.c:4171 > kmalloc_noprof include/linux/slab.h:694 [inline] > load_elf_phdrs+0x162/0x260 fs/binfmt_elf.c:526 > load_elf_binary+0x920/0x2680 fs/binfmt_elf.c:955 > search_binary_handler fs/exec.c:1820 [inline] > exec_binprm fs/exec.c:1862 [inline] > bprm_execve+0xaf8/0x1770 fs/exec.c:1913 > do_execveat_common+0x55f/0x6f0 fs/exec.c:2020 > do_execve fs/exec.c:2094 [inline] > __do_sys_execve fs/exec.c:2170 [inline] > __se_sys_execve fs/exec.c:2165 [inline] > __x64_sys_execve+0x92/0xb0 fs/exec.c:2165 > 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 > page last free pid 5032 tgid 5032 stack trace: > reset_page_owner include/linux/page_owner.h:25 [inline] > free_pages_prepare mm/page_alloc.c:1101 [inline] > free_unref_page+0xd22/0xea0 mm/page_alloc.c:2619 > __slab_free+0x31b/0x3d0 mm/slub.c:4385 > qlink_free mm/kasan/quarantine.c:163 [inline] > qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179 > kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 > __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 > kasan_slab_alloc include/linux/kasan.h:201 [inline] > slab_post_alloc_hook mm/slub.c:3989 [inline] > slab_alloc_node mm/slub.c:4038 [inline] > __do_kmalloc_node mm/slub.c:4158 [inline] > __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4171 > kmalloc_noprof include/linux/slab.h:694 [inline] > tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 > tomoyo_get_realpath security/tomoyo/file.c:151 [inline] > tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822 > security_inode_getattr+0x130/0x330 security/security.c:2371 > vfs_getattr+0x45/0x430 fs/stat.c:204 > vfs_fstat fs/stat.c:229 [inline] > vfs_fstatat+0xe4/0x190 fs/stat.c:338 > __do_sys_newfstatat fs/stat.c:505 [inline] > __se_sys_newfstatat fs/stat.c:499 [inline] > __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:499 > 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 > > Memory state around the buggy address: > ffff888036426700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff888036426780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > >ffff888036426800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ^ > ffff888036426880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffff888036426900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ================================================================== > > > --- > 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 > #syz test diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index 46ce2f21fef9..336badb46246 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -1776,7 +1776,14 @@ static int ext4_xattr_set_entry(struct ext4_xattr_info *i, } else if (s->not_found) { /* Insert new name. */ size_t size = EXT4_XATTR_LEN(name_len); - size_t rest = (void *)last - (void *)here + sizeof(__u32); + size_t rest; + + if (last < here) { + ret = -ENOSPC; + goto out; + } else { + rest = (void *)last - (void *)here + sizeof(__u32); + } memmove((void *)here + size, here, rest); memset(here, 0, size); -- Best, Qianqiang Liu