• Eric Dumazet's avatar
    tcp: fix error recovery in tcp_zerocopy_receive() · e776af60
    Eric Dumazet authored
    If user provides wrong virtual address in TCP_ZEROCOPY_RECEIVE
    operation we want to return -EINVAL error.
    
    But depending on zc->recv_skip_hint content, we might return
    -EIO error if the socket has SOCK_DONE set.
    
    Make sure to return -EINVAL in this case.
    
    BUG: KMSAN: uninit-value in tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline]
    BUG: KMSAN: uninit-value in do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685
    CPU: 1 PID: 625 Comm: syz-executor.0 Not tainted 5.7.0-rc4-syzkaller #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
    Call Trace:
     __dump_stack lib/dump_stack.c:77 [inline]
     dump_stack+0x1c9/0x220 lib/dump_stack.c:118
     kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
     __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
     tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline]
     do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685
     tcp_getsockopt+0xf8/0x1f0 net/ipv4/tcp.c:3728
     sock_common_getsockopt+0x13f/0x180 net/core/sock.c:3131
     __sys_getsockopt+0x533/0x7b0 net/socket.c:2177
     __do_sys_getsockopt net/socket.c:2192 [inline]
     __se_sys_getsockopt+0xe1/0x100 net/socket.c:2189
     __x64_sys_getsockopt+0x62/0x80 net/socket.c:2189
     do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297
     entry_SYSCALL_64_after_hwframe+0x44/0xa9
    RIP: 0033:0x45c829
    Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
    RSP: 002b:00007f1deeb72c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
    RAX: ffffffffffffffda RBX: 00000000004e01e0 RCX: 000000000045c829
    RDX: 0000000000000023 RSI: 0000000000000006 RDI: 0000000000000009
    RBP: 000000000078bf00 R08: 0000000020000200 R09: 0000000000000000
    R10: 00000000200001c0 R11: 0000000000000246 R12: 00000000ffffffff
    R13: 00000000000001d8 R14: 00000000004d3038 R15: 00007f1deeb736d4
    
    Local variable ----zc@do_tcp_getsockopt created at:
     do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670
     do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670
    
    Fixes: 05255b82 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
    Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
    Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
    Acked-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    e776af60
tcp.c 106 KB