[tor-bugs] #15436 [Tor]: Unaligned access in SipHash24 code

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#15436: Unaligned access in SipHash24 code
---------------------+------------------------------------
 Reporter:  pstumpf  |          Owner:
     Type:  defect   |         Status:  new
 Priority:  normal   |      Milestone:  Tor: 0.2.6.x-final
Component:  Tor      |        Version:  Tor: 0.2.5.11
 Keywords:           |  Actual Points:
Parent ID:           |         Points:
---------------------+------------------------------------
 Tor segfaults on OpenBSD/sparc64 on startup.  GDB backtrace:



 #0  siphash24 (src=0xfffffffffffcdc34, src_sz=20, key=Variable "key" is
 not avai
 lable.
 )
     at src/ext/csiphash.c:118
 118                     memcpy(&mi, in, 8);
 (gdb) bt
 #0  siphash24 (src=0xfffffffffffcdc34, src_sz=20, key=Variable "key" is
 not avai
 lable.
 )
     at src/ext/csiphash.c:118
 #1  0x00000026f1b853c8 in node_get_mutable_by_id (identity_digest=Variable
 "iden
 tity_digest" is not available.
 )


 As you can easily see, node_get_mutable_by_id passes an unaligned pointer
 to siphash24, which memcpy then tries to copy from.  This is a (struct
 node_t)->identity, so maybe that struct should have alignment padding?

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/15436>
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