• Avinash Repaka's avatar
    RDS: RDMA: Fix the NULL-ptr deref in rds_ib_get_mr · 9e630bcb
    Avinash Repaka authored
    Registration of a memory region(MR) through FRMR/fastreg(unlike FMR)
    needs a connection/qp. With a proxy qp, this dependency on connection
    will be removed, but that needs more infrastructure patches, which is a
    work in progress.
    
    As an intermediate fix, the get_mr returns EOPNOTSUPP when connection
    details are not populated. The MR registration through sendmsg() will
    continue to work even with fast registration, since connection in this
    case is formed upfront.
    
    This patch fixes the following crash:
    kasan: GPF could be caused by NULL-ptr deref or user memory access
    general protection fault: 0000 [#1] SMP KASAN
    Modules linked in:
    CPU: 1 PID: 4244 Comm: syzkaller468044 Not tainted 4.16.0-rc6+ #361
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
    Google 01/01/2011
    RIP: 0010:rds_ib_get_mr+0x5c/0x230 net/rds/ib_rdma.c:544
    RSP: 0018:ffff8801b059f890 EFLAGS: 00010202
    RAX: dffffc0000000000 RBX: ffff8801b07e1300 RCX: ffffffff8562d96e
    RDX: 000000000000000d RSI: 0000000000000001 RDI: 0000000000000068
    RBP: ffff8801b059f8b8 R08: ffffed0036274244 R09: ffff8801b13a1200
    R10: 0000000000000004 R11: ffffed0036274243 R12: ffff8801b13a1200
    R13: 0000000000000001 R14: ffff8801ca09fa9c R15: 0000000000000000
    FS:  00007f4d050af700(0000) GS:ffff8801db300000(0000)
    knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007f4d050aee78 CR3: 00000001b0d9b006 CR4: 00000000001606e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     __rds_rdma_map+0x710/0x1050 net/rds/rdma.c:271
     rds_get_mr_for_dest+0x1d4/0x2c0 net/rds/rdma.c:357
     rds_setsockopt+0x6cc/0x980 net/rds/af_rds.c:347
     SYSC_setsockopt net/socket.c:1849 [inline]
     SyS_setsockopt+0x189/0x360 net/socket.c:1828
     do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
     entry_SYSCALL_64_after_hwframe+0x42/0xb7
    RIP: 0033:0x4456d9
    RSP: 002b:00007f4d050aedb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
    RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 00000000004456d9
    RDX: 0000000000000007 RSI: 0000000000000114 RDI: 0000000000000004
    RBP: 00000000006dac38 R08: 00000000000000a0 R09: 0000000000000000
    R10: 0000000020000380 R11: 0000000000000246 R12: 0000000000000000
    R13: 00007fffbfb36d6f R14: 00007f4d050af9c0 R15: 0000000000000005
    Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 cc 01 00 00 4c 8b bb 80 04 00 00
    48
    b8 00 00 00 00 00 fc ff df 49 8d 7f 68 48 89 fa 48 c1 ea 03 <80> 3c 02
    00 0f
    85 9c 01 00 00 4d 8b 7f 68 48 b8 00 00 00 00 00
    RIP: rds_ib_get_mr+0x5c/0x230 net/rds/ib_rdma.c:544 RSP:
    ffff8801b059f890
    ---[ end trace 7e1cea13b85473b0 ]---
    
    Reported-by: syzbot+b51c77ef956678a65834@syzkaller.appspotmail.com
    Signed-off-by: default avatarSantosh Shilimkar <santosh.shilimkar@oracle.com>
    Signed-off-by: default avatarAvinash Repaka <avinash.repaka@oracle.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    9e630bcb
ib_rdma.c 16.3 KB