• Chao Yu's avatar
    f2fs: avoid panic when truncating to max filesize · 09210c97
    Chao Yu authored
    The following panic occurs when truncating inode which has inline
    xattr to max filesize.
    [<ffffffffa013d3be>] get_dnode_of_data+0x4e/0x580 [f2fs]
    [<ffffffffa013aca1>] ? read_node_page+0x51/0x90 [f2fs]
    [<ffffffffa013ad99>] ? get_node_page.part.34+0xb9/0x170 [f2fs]
    [<ffffffffa01235b1>] truncate_blocks+0x131/0x3f0 [f2fs]
    [<ffffffffa01238e3>] f2fs_truncate+0x73/0x100 [f2fs]
    [<ffffffffa01239d2>] f2fs_setattr+0x62/0x2a0 [f2fs]
    [<ffffffff811a72c8>] notify_change+0x158/0x300
    [<ffffffff8118a42b>] do_truncate+0x6b/0xa0
    [<ffffffff8118e539>] ? __sb_start_write+0x49/0x100
    [<ffffffff8118a798>] do_sys_ftruncate.constprop.12+0x118/0x170
    [<ffffffff8118a82e>] SyS_ftruncate+0xe/0x10
    [<ffffffff8169efcf>] tracesys+0xe1/0xe6
    [<ffffffffa0139ae0>] get_node_path+0x210/0x220 [f2fs]
    --[ end trace 5fea664dfbcc6625 ]---
    The reason is truncate_blocks tries to truncate all node and data blocks
    start from specified block offset with value of (max filesize / block
    size), but actually, our valid max block offset is (max filesize / block
    size) - 1, so f2fs detects such invalid block offset with BUG_ON in
    truncation path.
    This patch lets f2fs skip truncating data which is exceeding max
    Signed-off-by: default avatarChao Yu <yuchao0@huawei.com>
    Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
file.c 45.4 KB