On 2022/02/09 17:52, Lee Jones wrote: > This reverts commit 60263d5889e6dc5987dc51b801be4955ff2e4aa7. > > Reverting since this commit opens a potential avenue for abuse. > > The C-reproducer and more information can be found at the link below. > > With this patch applied, I can no longer get the repro to trigger. > > kernel BUG at fs/ext4/inode.c:2647! > invalid opcode: 0000 [#1] PREEMPT SMP KASAN > CPU: 0 PID: 459 Comm: syz-executor359 Tainted: G W 5.10.93-syzkaller-01028-g0347b1658399 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > RIP: 0010:mpage_prepare_extent_to_map+0xbe9/0xc00 fs/ext4/inode.c:2647 > Code: e8 fc bd c3 ff e9 80 f6 ff ff 44 89 e9 80 e1 07 38 c1 0f 8c a6 fe ff ff 4c 89 ef e8 e1 bd c3 ff e9 99 fe ff ff e8 87 c9 89 ff <0f> 0b e8 80 c9 89 ff 0f 0b e8 79 1e b8 02 66 0f 1f 84 00 00 00 00 > RSP: 0018:ffffc90000e2e9c0 EFLAGS: 00010293 > RAX: ffffffff81e321f9 RBX: 0000000000000000 RCX: ffff88810c12cf00 > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: ffffc90000e2eb90 R08: ffffffff81e31e71 R09: fffff940008d68b1 > R10: fffff940008d68b1 R11: 0000000000000000 R12: ffffea00046b4580 > R13: ffffc90000e2ea80 R14: 000000000000011e R15: dffffc0000000000 > FS: 00007fcfd0717700(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007fcfd07d5520 CR3: 000000010a142000 CR4: 00000000003506b0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > ext4_writepages+0xcbb/0x3950 fs/ext4/inode.c:2776 > do_writepages+0x13a/0x280 mm/page-writeback.c:2358 > __filemap_fdatawrite_range+0x356/0x420 mm/filemap.c:427 > filemap_write_and_wait_range+0x64/0xe0 mm/filemap.c:660 > __iomap_dio_rw+0x621/0x10c0 fs/iomap/direct-io.c:495 > iomap_dio_rw+0x35/0x80 fs/iomap/direct-io.c:611 > ext4_dio_write_iter fs/ext4/file.c:571 [inline] > ext4_file_write_iter+0xfc5/0x1b70 fs/ext4/file.c:681 > do_iter_readv_writev+0x548/0x740 include/linux/fs.h:1941 > do_iter_write+0x182/0x660 fs/read_write.c:866 > vfs_iter_write+0x7c/0xa0 fs/read_write.c:907 > iter_file_splice_write+0x7fb/0xf70 fs/splice.c:686 > do_splice_from fs/splice.c:764 [inline] > direct_splice_actor+0xfe/0x130 fs/splice.c:933 > splice_direct_to_actor+0x4f4/0xbc0 fs/splice.c:888 > do_splice_direct+0x28b/0x3e0 fs/splice.c:976 > do_sendfile+0x914/0x1390 fs/read_write.c:1257 > > Link: https://syzkaller.appspot.com/bug?extid=41c966bf0729a530bd8d > > From the patch: > Cc: Stable <stable@xxxxxxxxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Dave Chinner <dchinner@xxxxxxxxxx> > Cc: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> > Cc: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > Cc: Bob Peterson <rpeterso@xxxxxxxxxx> > Cc: Damien Le Moal <damien.lemoal@xxxxxxx> > Cc: Theodore Ts'o <tytso@xxxxxxx> # for ext4 > Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx> > Cc: Ritesh Harjani <riteshh@xxxxxxxxxxxxx> > > Others: > Cc: Johannes Thumshirn <jth@xxxxxxxxxx> > Cc: linux-xfs@xxxxxxxxxxxxxxx > Cc: linux-fsdevel@xxxxxxxxxxxxxxx > Cc: linux-ext4@xxxxxxxxxxxxxxx > Cc: cluster-devel@xxxxxxxxxx > > Fixes: 60263d5889e6d ("iomap: fall back to buffered writes for invalidation failures") > Reported-by: syzbot+0ed9f769264276638893@xxxxxxxxxxxxxxxxxxxxxxxxx > Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx> For zonefs: Acked-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx> -- Damien Le Moal Western Digital Research
