CVS commit: src/sys/kern

["Michael van Elst" <mlelstv%netbsd.org@localhost>]

Module Name:    src
Committed By:   mlelstv
Date:           Sat Dec 29 10:22:40 UTC 2012

Modified Files:
        src/sys/kern: uipc_syscalls.c

Log Message:
If an untraced process sleeps in recvmsg/sendmsg, the syscall does not
allocate an iov structure for ktrace. When tracing is then enabled
and the process wakes up, it crashes the kernel.

Undo the last commit which introduced this error path.

Avoid the mentioned kmem_alloc assertion by adding a sanity check analog
to similar code in sys_generic.c for I/O on file handles instead of
sockets.

This also causes the syscall to return EMSGSIZE if the msg_iovlen member
of the msg structure is less than or equal to 0, as defined in
recvmsg(2)/sendmsg(2).


To generate a diff of this commit:
cvs rdiff -u -r1.156 -r1.157 src/sys/kern/uipc_syscalls.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.