diff options
| author | Alexander Potapenko <glider@google.com> | 2022-10-12 17:25:14 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-10-14 08:20:17 +0100 |
| commit | 777ecaabd614d47c482a5c9031579e66da13989a (patch) | |
| tree | 708f8034b74aa868eaee3db1be22abcbed330fd9 /net | |
| parent | 28be7ca4fcfd69a2d52aaa331adbf9dbe91f9e6e (diff) | |
tipc: fix an information leak in tipc_topsrv_kern_subscr
Use a 8-byte write to initialize sub.usr_handle in
tipc_topsrv_kern_subscr(), otherwise four bytes remain uninitialized
when issuing setsockopt(..., SOL_TIPC, ...).
This resulted in an infoleak reported by KMSAN when the packet was
received:
=====================================================
BUG: KMSAN: kernel-infoleak in copyout+0xbc/0x100 lib/iov_iter.c:169
instrument_copy_to_user ./include/linux/instrumented.h:121
copyout+0xbc/0x100 lib/iov_iter.c:169
_copy_to_iter+0x5c0/0x20a0 lib/iov_iter.c:527
copy_to_iter ./include/linux/uio.h:176
simple_copy_to_iter+0x64/0xa0 net/core/datagram.c:513
__skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:419
skb_copy_datagram_iter+0x58/0x200 net/core/datagram.c:527
skb_copy_datagram_msg ./include/linux/skbuff.h:3903
packet_recvmsg+0x521/0x1e70 net/packet/af_packet.c:3469
____sys_recvmsg+0x2c4/0x810 net/socket.c:?
___sys_recvmsg+0x217/0x840 net/socket.c:2743
__sys_recvmsg net/socket.c:2773
__do_sys_recvmsg net/socket.c:2783
__se_sys_recvmsg net/socket.c:2780
__x64_sys_recvmsg+0x364/0x540 net/socket.c:2780
do_syscall_x64 arch/x86/entry/common.c:50
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd arch/x86/entry/entry_64.S:120
...
Uninit was stored to memory at:
tipc_sub_subscribe+0x42d/0xb50 net/tipc/subscr.c:156
tipc_conn_rcv_sub+0x246/0x620 net/tipc/topsrv.c:375
tipc_topsrv_kern_subscr+0x2e8/0x400 net/tipc/topsrv.c:579
tipc_group_create+0x4e7/0x7d0 net/tipc/group.c:190
tipc_sk_join+0x2a8/0x770 net/tipc/socket.c:3084
tipc_setsockopt+0xae5/0xe40 net/tipc/socket.c:3201
__sys_setsockopt+0x87f/0xdc0 net/socket.c:2252
__do_sys_setsockopt net/socket.c:2263
__se_sys_setsockopt net/socket.c:2260
__x64_sys_setsockopt+0xe0/0x160 net/socket.c:2260
do_syscall_x64 arch/x86/entry/common.c:50
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd arch/x86/entry/entry_64.S:120
Local variable sub created at:
tipc_topsrv_kern_subscr+0x57/0x400 net/tipc/topsrv.c:562
tipc_group_create+0x4e7/0x7d0 net/tipc/group.c:190
Bytes 84-87 of 88 are uninitialized
Memory access of size 88 starts at ffff88801ed57cd0
Data copied to user address 0000000020000400
...
=====================================================
Signed-off-by: Alexander Potapenko <glider@google.com>
Fixes: 026321c6d056a5 ("tipc: rename tipc_server to tipc_topsrv")
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/tipc/topsrv.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/tipc/topsrv.c b/net/tipc/topsrv.c index 5522865deae9..14fd05fd6107 100644 --- a/net/tipc/topsrv.c +++ b/net/tipc/topsrv.c @@ -568,7 +568,7 @@ bool tipc_topsrv_kern_subscr(struct net *net, u32 port, u32 type, u32 lower, sub.seq.upper = upper; sub.timeout = TIPC_WAIT_FOREVER; sub.filter = filter; - *(u32 *)&sub.usr_handle = port; + *(u64 *)&sub.usr_handle = (u64)port; con = tipc_conn_alloc(tipc_topsrv(net)); if (IS_ERR(con)) |