]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
bpf: fix 64-bit divide
authorAlexei Starovoitov <ast@plumgrid.com>
Mon, 27 Apr 2015 21:40:37 +0000 (14:40 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 13 May 2015 12:14:16 +0000 (05:14 -0700)
commit59506497a7c844e81254c0a4bc2920510fac9a52
tree18e5e9312d46141b6dac6263d52c8fe29d9b70ad
parent072cab659c9368586d6417cfd6ec2d2c68469c67
bpf: fix 64-bit divide

[ Upstream commit 876a7ae65b86d8cec8efe7d15d050ac61116874e ]

ALU64_DIV instruction should be dividing 64-bit by 64-bit,
whereas do_div() does 64-bit by 32-bit divide.
x64 and arm64 JITs correctly implement 64 by 64 unsigned divide.
llvm BPF backend emits code assuming that ALU64_DIV does 64 by 64.

Fixes: 89aa075832b0 ("net: sock: allow eBPF programs to be attached to sockets")
Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/bpf/core.c