[LU-15933] client hang with NULL pointer dereference, at iov_iter_advance

• Type: Bug
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.16.0, Lustre 2.15.1
• Environment: client kernel version >= 5.13
• Severity: 3
• Assignee: Zhenyu Xu
• Reporter: Zhenyu Xu

Description

lustre clients hang with following call trace.

      BUG: kernel NULL pointer dereference, address: 0000000000000008
      RIP: 0010:iov_iter_advance+0x1ef/0x260
      Call Trace:
       vvp_io_rw_lock+0x240/0x7e0 [lustre]
       vvp_io_read_lock+0x3f/0xd0 [lustre]
       cl_io_lock+0x62/0x2d0 [obdclass]
       cl_io_loop+0x8b/0x1f0 [obdclass]
       ll_file_io_generic+0x436/0xd60 [lustre]
       ll_file_read_iter+0x42c/0x5d0 [lustre]
       generic_file_splice_read+0xf7/0x1a0
       do_splice_to+0x81/0xb0
       splice_direct_to_actor+0xbc/0x230
       ? opipe_prep.part.0+0xb0/0xb0
       do_splice_direct+0x89/0xd0
       do_sendfile+0x303/0x450