s390/bpf,jit: initialize A register if 1st insn is BPF_S_LDX_B_MSH
authorMartin Schwidefsky <schwidefsky@de.ibm.com>
Fri, 25 Apr 2014 08:53:44 +0000 (10:53 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 13 May 2014 11:32:49 +0000 (13:32 +0200)
commitc180afb403eaabbd3a233832abcc7e50e988de8e
treeb9f1c22edac5a48c92fb07efd25a09bdd1b478a0
parent8ba2a0e0643ffcc64f3e9f986e6934ba228d433d
s390/bpf,jit: initialize A register if 1st insn is BPF_S_LDX_B_MSH

commit 6e0de817594c61f3b392a9245deeb09609ec707d upstream.

The A register needs to be initialized to zero in the prolog if the
first instruction of the BPF program is BPF_S_LDX_B_MSH to prevent
leaking the content of %r5 to user space.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/s390/net/bpf_jit_comp.c