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authorLinus Torvalds <torvalds@linux-foundation.org>2018-02-23 15:14:17 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2018-02-23 15:14:17 -0800
commit9cb9c07d6b0c5fd97d83b8ab14d7e308ba4b612f (patch)
treeb0c3add28508577157a1012474d38d785a84159c /arch/x86/include/asm/nospec-branch.h
parent2eb02aa94f99ae2b94ab3c42d5d605128fd5c0c5 (diff)
parenta5f7add332b4ea6d4b9480971b3b0f5e66466ae9 (diff)
downloadlinux-9cb9c07d6b0c5fd97d83b8ab14d7e308ba4b612f.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller: 1) Fix TTL offset calculation in mac80211 mesh code, from Peter Oh. 2) Fix races with procfs in ipt_CLUSTERIP, from Cong Wang. 3) Memory leak fix in lpm_trie BPF map code, from Yonghong Song. 4) Need to use GFP_ATOMIC in BPF cpumap allocations, from Jason Wang. 5) Fix potential deadlocks in netfilter getsockopt() code paths, from Paolo Abeni. 6) Netfilter stackpointer size checks really are needed to validate user input, from Florian Westphal. 7) Missing timer init in x_tables, from Paolo Abeni. 8) Don't use WQ_MEM_RECLAIM in mac80211 hwsim, from Johannes Berg. 9) When an ibmvnic device is brought down then back up again, it can be sent queue entries from a previous session, handle this properly instead of crashing. From Thomas Falcon. 10) Fix TCP checksum on LRO buffers in mlx5e, from Gal Pressman. 11) When we are dumping filters in cls_api, the output SKB is empty, and the filter we are dumping is too large for the space in the SKB, we should return -EMSGSIZE like other netlink dump operations do. Otherwise userland has no signal that is needs to increase the size of its read buffer. From Roman Kapl. 12) Several XDP fixes for virtio_net, from Jesper Dangaard Brouer. 13) Module refcount leak in netlink when a dump start fails, from Jason Donenfeld. 14) Handle sub-optimal GSO sizes better in TCP BBR congestion control, from Eric Dumazet. 15) Releasing bpf per-cpu arraymaps can take a long time, add a condtional scheduling point. From Eric Dumazet. 16) Implement retpolines for tail calls in x64 and arm64 bpf JITs. From Daniel Borkmann. 17) Fix page leak in gianfar driver, from Andy Spencer. 18) Missed clearing of estimator scratch buffer, from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits) net_sched: gen_estimator: fix broken estimators based on percpu stats gianfar: simplify FCS handling and fix memory leak ipv6 sit: work around bogus gcc-8 -Wrestrict warning macvlan: fix use-after-free in macvlan_common_newlink() bpf, arm64: fix out of bounds access in tail call bpf, x64: implement retpoline for tail call rxrpc: Fix send in rxrpc_send_data_packet() net: aquantia: Fix error handling in aq_pci_probe() bpf: fix rcu lockdep warning for lpm_trie map_free callback bpf: add schedule points in percpu arrays management regulatory: add NUL to request alpha2 ibmvnic: Fix early release of login buffer net/smc9194: Remove bogus CONFIG_MAC reference net: ipv4: Set addr_type in hash_keys for forwarded case tcp_bbr: better deal with suboptimal GSO smsc75xx: fix smsc75xx_set_features() netlink: put module reference if dump start fails selftests/bpf/test_maps: exit child process without error in ENOMEM case selftests/bpf: update gitignore with test_libbpf_open selftests/bpf: tcpbpf_kern: use in6_* macros from glibc ..
Diffstat (limited to 'arch/x86/include/asm/nospec-branch.h')
-rw-r--r--arch/x86/include/asm/nospec-branch.h37
1 files changed, 37 insertions, 0 deletions
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 76b058533e47..81a1be326571 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -177,4 +177,41 @@ static inline void indirect_branch_prediction_barrier(void)
}
#endif /* __ASSEMBLY__ */
+
+/*
+ * Below is used in the eBPF JIT compiler and emits the byte sequence
+ * for the following assembly:
+ *
+ * With retpolines configured:
+ *
+ * callq do_rop
+ * spec_trap:
+ * pause
+ * lfence
+ * jmp spec_trap
+ * do_rop:
+ * mov %rax,(%rsp)
+ * retq
+ *
+ * Without retpolines configured:
+ *
+ * jmp *%rax
+ */
+#ifdef CONFIG_RETPOLINE
+# define RETPOLINE_RAX_BPF_JIT_SIZE 17
+# define RETPOLINE_RAX_BPF_JIT() \
+ EMIT1_off32(0xE8, 7); /* callq do_rop */ \
+ /* spec_trap: */ \
+ EMIT2(0xF3, 0x90); /* pause */ \
+ EMIT3(0x0F, 0xAE, 0xE8); /* lfence */ \
+ EMIT2(0xEB, 0xF9); /* jmp spec_trap */ \
+ /* do_rop: */ \
+ EMIT4(0x48, 0x89, 0x04, 0x24); /* mov %rax,(%rsp) */ \
+ EMIT1(0xC3); /* retq */
+#else
+# define RETPOLINE_RAX_BPF_JIT_SIZE 2
+# define RETPOLINE_RAX_BPF_JIT() \
+ EMIT2(0xFF, 0xE0); /* jmp *%rax */
+#endif
+
#endif /* _ASM_X86_NOSPEC_BRANCH_H_ */