• Hongyu Jin's avatar
    erofs: fix use-after-free of on-stack io[] · 60b30050
    Hongyu Jin authored
    The root cause is the race as follows:
    Thread #1                              Thread #2(irq ctx)
    
    z_erofs_runqueue()
      struct z_erofs_decompressqueue io_A[];
      submit bio A
      z_erofs_decompress_kickoff(,,1)
                                           z_erofs_decompressqueue_endio(bio A)
                                           z_erofs_decompress_kickoff(,,-1)
                                           spin_lock_irqsave()
                                           atomic_add_return()
      io_wait_event()	-> pending_bios is already 0
      [end of function]
                                           wake_up_locked(io_A[]) // crash
    
    Referenced backtrace in kernel 5.4:
    
    [   10.129422] Unable to handle kernel paging request at virtual address eb0454a4
    [   10.364157] CPU: 0 PID: 709 Comm: getprop Tainted: G        WC O      5.4.147-ab09225 #1
    [   11.556325] [<c01b33b8>] (__wake_up_common) from [<c01b3300>] (__wake_up_locked+0x40/0x48)
    [   11.565487] [<c01b3300>] (__wake_up_locked) from [<c044c8d0>] (z_erofs_vle_unzip_kickoff+0x6c/0xc0)
    [   11.575438] [<c044c8d0>] (z_erofs_vle_unzip_kickoff) from [<c044c854>] (z_erofs_vle_read_endio+0x16c/0x17c)
    [   11.586082] [<c044c854>] (z_erofs_vle_read_endio) from [<c06a80e8>] (clone_endio+0xb4/0x1d0)
    [   11.595428] [<c06a80e8>] (clone_endio) from [<c04a1280>] (blk_update_request+0x150/0x4dc)
    [   11.604516] [<c04a1280>] (blk_update_request) from [<c06dea28>] (mmc_blk_cqe_complete_rq+0x144/0x15c)
    [   11.614640] [<c06dea28>] (mmc_blk_cqe_complete_rq) from [<c04a5d90>] (blk_done_softirq+0xb0/0xcc)
    [   11.624419] [<c04a5d90>] (blk_done_softirq) from [<c010242c>] (__do_softirq+0x184/0x56c)
    [   11.633419] [<c010242c>] (__do_softirq) from [<c01051e8>] (irq_exit+0xd4/0x138)
    [   11.641640] [<c01051e8>] (irq_exit) from [<c010c314>] (__handle_domain_irq+0x94/0xd0)
    [   11.650381] [<c010c314>] (__handle_domain_irq) from [<c04fde70>] (gic_handle_irq+0x50/0xd4)
    [   11.659641] [<c04fde70>] (gic_handle_irq) from [<c0101b70>] (__irq_svc+0x70/0xb0)
    Signed-off-by: default avatarHongyu Jin <hongyu.jin@unisoc.com>
    Reviewed-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
    Reviewed-by: default avatarChao Yu <chao@kernel.org>
    Link: https://lore.kernel.org/r/20220401115527.4935-1-hongyu.jin.cn@gmail.comSigned-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
    60b30050
zdata.h 4.91 KB