user/sven/linux.git/kernel/seccomp.c, branch v4.1.41

seccomp: always propagate NO_NEW_PRIVS on tsync

2016-02-15T20:45:25Z

[ Upstream commit 103502a35cfce0710909da874f092cb44823ca03 ] Before this patch, a process with some permissive seccomp filter that was applied by root without NO_NEW_PRIVS was able to add more filters to itself without setting NO_NEW_PRIVS by setting the new filter from a throwaway thread with NO_NEW_PRIVS. Signed-off-by: Jann Horn Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: Sasha Levin

seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO

2015-02-17T22:34:55Z

The value resulting from the SECCOMP_RET_DATA mask could exceed MAX_ERRNO when setting errno during a SECCOMP_RET_ERRNO filter action. This makes sure we have a reliable value being set, so that an invalid errno will not be ignored by userspace. Signed-off-by: Kees Cook Reported-by: Dmitry V. Levin Cc: Andy Lutomirski Cc: Will Drewry Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2014-10-14T00:27:06Z

Pull x86 seccomp changes from Ingo Molnar: "This tree includes x86 seccomp filter speedups and related preparatory work, which touches core seccomp facilities as well. The main idea is to split seccomp into two phases, to be able to enter a simple fast path for syscalls with ptrace side effects. There's no substantial user-visible (and ABI) effects expected from this, except a change in how we emit a better audit record for SECCOMP_RET_TRACE events" * 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86_64, entry: Use split-phase syscall_trace_enter for 64-bit syscalls x86_64, entry: Treat regs->ax the same in fastpath and slowpath syscalls x86: Split syscall_trace_enter into two phases x86, entry: Only call user_exit if TIF_NOHZ x86, x32, audit: Fix x32's AUDIT_ARCH wrt audit seccomp: Document two-phase seccomp and arch-provided seccomp_data seccomp: Allow arch code to provide seccomp_data seccomp: Refactor the filter callback and the API seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computing

net: bpf: make eBPF interpreter images read-only

2014-09-05T19:02:48Z

With eBPF getting more extended and exposure to user space is on it's way, hardening the memory range the interpreter uses to steer its command flow seems appropriate. This patch moves the to be interpreted bytecode to read-only pages. In case we execute a corrupted BPF interpreter image for some reason e.g. caused by an attacker which got past a verifier stage, it would not only provide arbitrary read/write memory access but arbitrary function calls as well. After setting up the BPF interpreter image, its contents do not change until destruction time, thus we can setup the image on immutable made pages in order to mitigate modifications to that code. The idea is derived from commit 314beb9bcabf ("x86: bpf_jit_comp: secure bpf jit against spraying attacks"). This is possible because bpf_prog is not part of sk_filter anymore. After setup bpf_prog cannot be altered during its life-time. This prevents any modifications to the entire bpf_prog structure (incl. function/JIT image pointer). Every eBPF program (including classic BPF that are migrated) have to call bpf_prog_select_runtime() to select either interpreter or a JIT image as a last setup step, and they all are being freed via bpf_prog_free(), including non-JIT. Therefore, we can easily integrate this into the eBPF life-time, plus since we directly allocate a bpf_prog, we have no performance penalty. Tested with seccomp and test_bpf testsuite in JIT/non-JIT mode and manual inspection of kernel_page_tables. Brad Spengler proposed the same idea via Twitter during development of this patch. Joint work with Hannes Frederic Sowa. Suggested-by: Brad Spengler Signed-off-by: Daniel Borkmann Signed-off-by: Hannes Frederic Sowa Cc: Alexei Starovoitov Cc: Kees Cook Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

seccomp: Allow arch code to provide seccomp_data

2014-09-03T21:58:17Z

populate_seccomp_data is expensive: it works by inspecting task_pt_regs and various other bits to piece together all the information, and it's does so in multiple partially redundant steps. Arch-specific code in the syscall entry path can do much better. Admittedly this adds a bit of additional room for error, but the speedup should be worth it. Signed-off-by: Andy Lutomirski Signed-off-by: Kees Cook

seccomp: Refactor the filter callback and the API

2014-09-03T21:58:17Z

The reason I did this is to add a seccomp API that will be usable for an x86 fast path. The x86 entry code needs to use a rather expensive slow path for a syscall that might be visible to things like ptrace. By splitting seccomp into two phases, we can check whether we need the slow path and then use the fast path in if the filter allows the syscall or just returns some errno. As a side effect, I think the new code is much easier to understand than the old code. This has one user-visible effect: the audit record written for SECCOMP_RET_TRACE is now a simple indication that SECCOMP_RET_TRACE happened. It used to depend in a complicated way on what the tracer did. I couldn't make much sense of it. Signed-off-by: Andy Lutomirski Signed-off-by: Kees Cook

seccomp,x86,arm,mips,s390: Remove nr parameter from secure_computing

2014-09-03T21:58:17Z

The secure_computing function took a syscall number parameter, but it only paid any attention to that parameter if seccomp mode 1 was enabled. Rather than coming up with a kludge to get the parameter to work in mode 2, just remove the parameter. To avoid churn in arches that don't have seccomp filters (and may not even support syscall_get_nr right now), this leaves the parameter in secure_computing_strict, which is now a real function. For ARM, this is a bit ugly due to the fact that ARM conditionally supports seccomp filters. Fixing that would probably only be a couple of lines of code, but it should be coordinated with the audit maintainers. This will be a slight slowdown on some arches. The right fix is to pass in all of seccomp_data instead of trying to make just the syscall nr part be fast. This is a prerequisite for making two-phase seccomp work cleanly. Cc: Russell King Cc: linux-arm-kernel@lists.infradead.org Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: linux-s390@vger.kernel.org Cc: x86@kernel.org Cc: Kees Cook Signed-off-by: Andy Lutomirski Signed-off-by: Kees Cook

seccomp: Replace BUG(!spin_is_locked()) with assert_spin_lock

2014-08-11T20:29:12Z

Current upstream kernel hangs with mips and powerpc targets in uniprocessor mode if SECCOMP is configured. Bisect points to commit dbd952127d11 ("seccomp: introduce writer locking"). Turns out that code such as BUG_ON(!spin_is_locked(&list_lock)); can not be used in uniprocessor mode because spin_is_locked() always returns false in this configuration, and that assert_spin_locked() exists for that very purpose and must be used instead. Fixes: dbd952127d11 ("seccomp: introduce writer locking") Cc: Kees Cook Signed-off-by: Guenter Roeck Signed-off-by: Kees Cook

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2014-08-06T16:38:14Z

Pull networking updates from David Miller: "Highlights: 1) Steady transitioning of the BPF instructure to a generic spot so all kernel subsystems can make use of it, from Alexei Starovoitov. 2) SFC driver supports busy polling, from Alexandre Rames. 3) Take advantage of hash table in UDP multicast delivery, from David Held. 4) Lighten locking, in particular by getting rid of the LRU lists, in inet frag handling. From Florian Westphal. 5) Add support for various RFC6458 control messages in SCTP, from Geir Ola Vaagland. 6) Allow to filter bridge forwarding database dumps by device, from Jamal Hadi Salim. 7) virtio-net also now supports busy polling, from Jason Wang. 8) Some low level optimization tweaks in pktgen from Jesper Dangaard Brouer. 9) Add support for ipv6 address generation modes, so that userland can have some input into the process. From Jiri Pirko. 10) Consolidate common TCP connection request code in ipv4 and ipv6, from Octavian Purdila. 11) New ARP packet logger in netfilter, from Pablo Neira Ayuso. 12) Generic resizable RCU hash table, with intial users in netlink and nftables. From Thomas Graf. 13) Maintain a name assignment type so that userspace can see where a network device name came from (enumerated by kernel, assigned explicitly by userspace, etc.) From Tom Gundersen. 14) Automatic flow label generation on transmit in ipv6, from Tom Herbert. 15) New packet timestamping facilities from Willem de Bruijn, meant to assist in measuring latencies going into/out-of the packet scheduler, latency from TCP data transmission to ACK, etc" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1536 commits) cxgb4 : Disable recursive mailbox commands when enabling vi net: reduce USB network driver config options. tg3: Modify tg3_tso_bug() to handle multiple TX rings amd-xgbe: Perform phy connect/disconnect at dev open/stop amd-xgbe: Use dma_set_mask_and_coherent to set DMA mask net: sun4i-emac: fix memory leak on bad packet sctp: fix possible seqlock seadlock in sctp_packet_transmit() Revert "net: phy: Set the driver when registering an MDIO bus device" cxgb4vf: Turn off SGE RX/TX Callback Timers and interrupts in PCI shutdown routine team: Simplify return path of team_newlink bridge: Update outdated comment on promiscuous mode net-timestamp: ACK timestamp for bytestreams net-timestamp: TCP timestamping net-timestamp: SCHED timestamp on entering packet scheduler net-timestamp: add key to disambiguate concurrent datagrams net-timestamp: move timestamp flags out of sk_flags net-timestamp: extend SCM_TIMESTAMPING ancillary data struct cxgb4i : Move stray CPL definitions to cxgb4 driver tcp: reduce spurious retransmits due to transient SACK reneging qlcnic: Initialize dcbnl_ops before register_netdev ...

net: filter: split 'struct sk_filter' into socket and bpf parts

2014-08-02T22:03:58Z

clean up names related to socket filtering and bpf in the following way: - everything that deals with sockets keeps 'sk_*' prefix - everything that is pure BPF is changed to 'bpf_*' prefix split 'struct sk_filter' into struct sk_filter { atomic_t refcnt; struct rcu_head rcu; struct bpf_prog *prog; }; and struct bpf_prog { u32 jited:1, len:31; struct sock_fprog_kern *orig_prog; unsigned int (*bpf_func)(const struct sk_buff *skb, const struct bpf_insn *filter); union { struct sock_filter insns[0]; struct bpf_insn insnsi[0]; struct work_struct work; }; }; so that 'struct bpf_prog' can be used independent of sockets and cleans up 'unattached' bpf use cases split SK_RUN_FILTER macro into: SK_RUN_FILTER to be used with 'struct sk_filter *' and BPF_PROG_RUN to be used with 'struct bpf_prog *' __sk_filter_release(struct sk_filter *) gains __bpf_prog_release(struct bpf_prog *) helper function also perform related renames for the functions that work with 'struct bpf_prog *', since they're on the same lines: sk_filter_size -> bpf_prog_size sk_filter_select_runtime -> bpf_prog_select_runtime sk_filter_free -> bpf_prog_free sk_unattached_filter_create -> bpf_prog_create sk_unattached_filter_destroy -> bpf_prog_destroy sk_store_orig_filter -> bpf_prog_store_orig_filter sk_release_orig_filter -> bpf_release_orig_filter __sk_migrate_filter -> bpf_migrate_filter __sk_prepare_filter -> bpf_prepare_filter API for attaching classic BPF to a socket stays the same: sk_attach_filter(prog, struct sock *)/sk_detach_filter(struct sock *) and SK_RUN_FILTER(struct sk_filter *, ctx) to execute a program which is used by sockets, tun, af_packet API for 'unattached' BPF programs becomes: bpf_prog_create(struct bpf_prog **)/bpf_prog_destroy(struct bpf_prog *) and BPF_PROG_RUN(struct bpf_prog *, ctx) to execute a program which is used by isdn, ppp, team, seccomp, ptp, xt_bpf, cls_bpf, test_bpf Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller