- 19 Aug, 2017 1 commit
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Taehee Yoo authored
The root4 variable is used only when connlimit extension module has been stored by the iptables command. and the roo6 variable is used only when connlimit extension module has been stored by the ip6tables command. So the root4 and roo6 variable does not be used at the same time. Signed-off-by:
Taehee Yoo <ap420073@gmail.com> Signed-off-by:
Pablo Neira Ayuso <pablo@netfilter.org>
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- 02 Aug, 2017 3 commits
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Julia Lawall authored
The nf_loginfo structures are only passed as the seventh argument to nf_log_trace, which is declared as const or stored in a local const variable. Thus the nf_loginfo structures themselves can be const. Done with the help of Coccinelle. // <smpl> @r disable optional_qualifier@ identifier i; position p; @@ static struct nf_loginfo i@p = { ... }; @ok1@ identifier r.i; expression list[6] es; position p; @@ nf_log_trace(es,&i@p,...) @ok2@ identifier r.i; const struct nf_loginfo *e; position p; @@ e = &i@p @bad@ position p != {r.p,ok1.p,ok2.p}; identifier r.i; struct nf_loginfo e; @@ e@i@p @depends on !bad disable optional_qualifier@ identifier r.i; @@ static +const struct nf_loginfo i = { ... }; // </smpl> Signed-off-by:Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by:
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Julia Lawall authored
When a nf_conntrack_l3/4proto parameter is not on the left hand side of an assignment, its address is not taken, and it is not passed to a function that may modify its fields, then it can be declared as const. This change is useful from a documentation point of view, and can possibly facilitate making some nf_conntrack_l3/4proto structures const subsequently. Done with the help of Coccinelle. Signed-off-by:
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Taehee Yoo authored
The target variable is not used in the compat_copy_entry_from_user(). So It can be removed. Signed-off-by:
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- 31 Jul, 2017 16 commits
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Florian Westphal authored
Discussion during NFWS 2017 in Faro has shown that the current conntrack behaviour is unreasonable. Even if conntrack module is loaded on behalf of a single net namespace, its turned on for all namespaces, which is expensive. Commit 481fa373 ("netfilter: conntrack: add nf_conntrack_default_on sysctl") attempted to provide an alternative to the 'default on' behaviour by adding a sysctl to change it. However, as Eric points out, the sysctl only becomes available once the module is loaded, and then its too late. So we either have to move the sysctl to the core, or, alternatively, change conntrack to become active only once the rule set requires this. This does the latter, conntrack is only enabled when a rule needs it. Reported-by:
Eric Dumazet <edumazet@google.com> Signed-off-by:
Florian Westphal <fw@strlen.de> Signed-off-by:
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Florian Westphal authored
switch to lockless lockup. write side now also increments sequence counter. On lookup, sample counter value and only take the lock if we did not find a match and the counter has changed. This avoids need to write to private area in normal (lookup) cases. In case we detect a writer (seqretry is true) we fall back to taking the readlock. The readlock is also used during dumps to ensure we get a consistent tree walk. Similar technique (rbtree+seqlock) was used by David Howells in rxrpc. Signed-off-by:
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Phil Sutter authored
Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by:
Phil Sutter <phil@nwl.cc> Signed-off-by:
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Phil Sutter authored
Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by:
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Phil Sutter authored
Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by:
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Phil Sutter authored
Allocate all table names dynamically to allow for arbitrary lengths but introduce NFT_NAME_MAXLEN as an upper sanity boundary. It's value was chosen to allow using a domain name as per RFC 1035. Signed-off-by:
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Phil Sutter authored
This is similar to strdup() for netlink string attributes. Signed-off-by:
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Phil Sutter authored
nft_trace_notify() is called only from __nft_trace_packet(), which assigns its parameter 'chain' to info->chain. __nft_trace_packet() in turn later dereferences 'chain' unconditionally, which indicates that it's never NULL. Same does nft_do_chain(), the only user of the tracing infrastructure. Hence it is safe to assume the check removed here is not needed. Signed-off-by:
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Florian Westphal authored
We no longer place these on a list so they can be const. Signed-off-by:
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Florian Westphal authored
When skb is queued to userspace it leaves softirq/rcu protection. skb->nfct (via conntrack extensions such as helper) could then reference modules that no longer exist if the conntrack was not yet confirmed. nf_ct_iterate_destroy() will set the DYING bit for unconfirmed conntracks, we therefore solve this race as follows: 1. take the queue spinlock. 2. check if the conntrack is unconfirmed and has dying bit set. In this case, we must discard skb while we're still inside rcu read-side section. 3. If nf_ct_iterate_destroy() is called right after the packet is queued to userspace, it will be removed from the queue via nf_ct_iterate_destroy -> nf_queue_nf_hook_drop. When userspace sends the verdict (nfnetlink takes rcu read lock), there are two cases to consider: 1. nf_ct_iterate_destroy() was called while packet was out. In this case, skb will have been removed from the queue already and no reinject takes place as we won't find a matching entry for the packet id. 2. nf_ct_iterate_destroy() gets called right after verdict callback found and removed the skb from queue list. In this case, skb->nfct is marked as dying but it is still valid. The skb will be dropped either in nf_conntrack_confirm (we don't insert DYING conntracks into hash table) or when we try to queue the skb again, but either events don't occur before the rcu read lock is dropped. Signed-off-by:
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Florian Westphal authored
queued skbs might be using conntrack extensions that are being removed, such as timeout. This happens for skbs that have a skb->nfct in unconfirmed state (i.e., not in hash table yet). This is destructive, but there are only two use cases: - module removal (rare) - netns cleanup (most likely no conntracks exist, and if they do, they are removed anyway later on). Signed-off-by:
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Florian Westphal authored
This also removes __nf_ct_unconfirmed_destroy() call from nf_ct_iterate_cleanup_net, so that function can be used only when missing conntracks from unconfirmed list isn't a problem. Signed-off-by:
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Florian Westphal authored
We have several spots that open-code a expect walk, add a helper that is similar to nf_ct_iterate_destroy/nf_ct_iterate_cleanup. Signed-off-by:
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subashab@codeaurora.org authored
Delayed workqueue causes wakeups to idle CPUs. This was causing a power impact for devices. Use deferable work queue instead so that gc_worker runs when CPU is active only. Signed-off-by:
Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Signed-off-by:
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Pablo M. Bermudo Garay authored
Add fib expression support for netdev family. Like inet family, netdev delegates the actual decision to the corresponding backend, either ipv4 or ipv6. This allows to perform very early reverse path filtering, among other things. You can find more information about fib expression in the f6d0cbcf ("<netfilter: nf_tables: add fib expression>") commit message. Signed-off-by:
Pablo M. Bermudo Garay <pablombg@gmail.com> Signed-off-by:
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Pablo M. Bermudo Garay authored
This is a preparatory patch for adding fib support to the netdev family. The netdev family receives the packets from ingress hook. At this point we have no guarantee that the ip header is linear. So this patch replaces ip_hdr with skb_header_pointer in order to address that possible situation. Signed-off-by:
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- 24 Jul, 2017 4 commits
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Phil Sutter authored
This is helpful for 'nft monitor' to track which process caused a given change to the ruleset. Signed-off-by:
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Taehee Yoo authored
This patch removes duplicate rcu_read_lock(). 1. IPVS part: According to Julian Anastasov's mention, contexts of ipvs are described at: http://marc.info/?l=netfilter-devel&m=149562884514072&w=2, in summary: - packet RX/TX: does not need locks because packets come from hooks. - sync msg RX: backup server uses RCU locks while registering new connections. - ip_vs_ctl.c: configuration get/set, RCU locks needed. - xt_ipvs.c: It is a netfilter match, running from hook context. As result, rcu_read_lock and rcu_read_unlock can be removed from: - ip_vs_core.c: all - ip_vs_ctl.c: - only from ip_vs_has_real_service - ip_vs_ftp.c: all - ip_vs_proto_sctp.c: all - ip_vs_proto_tcp.c: all - ip_vs_proto_udp.c: all - ip_vs_xmit.c: all (contains only packet processing) 2. Netfilter part: There are three types of functions that are guaranteed the rcu_read_lock(). First, as result, functions are only called by nf_hook(): - nf_conntrack_broadcast_help(), pptp_expectfn(), set_expected_rtp_rtcp(). - tcpmss_reverse_mtu(), tproxy_laddr4(), tproxy_laddr6(). - match_lookup_rt6(), check_hlist(), hashlimit_mt_common(). - xt_osf_match_packet(). Second, functions that caller already held the rcu_read_lock(). - destroy_conntrack(), ctnetlink_conntrack_event(). - ctnl_timeout_find_get(), nfqnl_nf_hook_drop(). Third, functions that are mixed with type1 and type2. These functions are called by nf_hook() also these are called by ordinary functions that already held the rcu_read_lock(): - __ctnetlink_glue_build(), ctnetlink_expect_event(). - ctnetlink_proto_size(). Applied files are below: - nf_conntrack_broadcast.c, nf_conntrack_core.c, nf_conntrack_netlink.c. - nf_conntrack_pptp.c, nf_conntrack_sip.c, nfnetlink_cttimeout.c. - nfnetlink_queue.c, xt_TCPMSS.c, xt_TPROXY.c, xt_addrtype.c. - xt_connlimit.c, xt_hashlimit.c, xt_osf.c Detailed calltrace can be found at: http://marc.info/?l=netfilter-devel&m=149667610710350&w=2Signed-off-by:
Julian Anastasov <ja@ssi.bg> Signed-off-by:
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Pablo Neira Ayuso authored
These chain counters are only used by the iptables-compat tool, that allow users to use the x_tables extensions from the existing nf_tables framework. This patch makes nf_tables by ~5% for the general usecase, ie. native nft users, where no chain counters are used at all. Signed-off-by: -
Florian Westphal authored
assuming we have lockless readers we should make sure they can only see expectations that have already been initialized. hlist_add_head_rcu acts as memory barrier, move it after timer setup. Theoretically we could crash due to a del_timer() on other cpu seeing garbage data. Signed-off-by:
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- 21 Jul, 2017 1 commit
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- 20 Jul, 2017 15 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) BPF verifier signed/unsigned value tracking fix, from Daniel Borkmann, Edward Cree, and Josef Bacik. 2) Fix memory allocation length when setting up calls to ->ndo_set_mac_address, from Cong Wang. 3) Add a new cxgb4 device ID, from Ganesh Goudar. 4) Fix FIB refcount handling, we have to set it's initial value before the configure callback (which can bump it). From David Ahern. 5) Fix double-free in qcom/emac driver, from Timur Tabi. 6) A bunch of gcc-7 string format overflow warning fixes from Arnd Bergmann. 7) Fix link level headroom tests in ip_do_fragment(), from Vasily Averin. 8) Fix chunk walking in SCTP when iterating over error and parameter headers. From Alexander Potapenko. 9) TCP BBR congestion control fixes from Neal Cardwell. 10) Fix SKB fragment handling in bcmgenet driver, from Doug Berger. 11) BPF_CGROUP_RUN_PROG_SOCK_OPS needs to check for null __sk, from Cong Wang. 12) xmit_recursion in ppp driver needs to be per-device not per-cpu, from Gao Feng. 13) Cannot release skb->dst in UDP if IP options processing needs it. From Paolo Abeni. 14) Some netdev ioctl ifr_name[] NULL termination fixes. From Alexander Levin and myself. 15) Revert some rtnetlink notification changes that are causing regressions, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (83 commits) net: bonding: Fix transmit load balancing in balance-alb mode rds: Make sure updates to cp_send_gen can be observed net: ethernet: ti: cpsw: Push the request_irq function to the end of probe ipv4: initialize fib_trie prior to register_netdev_notifier call. rtnetlink: allocate more memory for dev_set_mac_address() net: dsa: b53: Add missing ARL entries for BCM53125 bpf: more tests for mixed signed and unsigned bounds checks bpf: add test for mixed signed and unsigned bounds checks bpf: fix up test cases with mixed signed/unsigned bounds bpf: allow to specify log level and reduce it for test_verifier bpf: fix mixed signed/unsigned derived min/max value bounds ipv6: avoid overflow of offset in ip6_find_1stfragopt net: tehuti: don't process data if it has not been copied from userspace Revert "rtnetlink: Do not generate notifications for CHANGEADDR event" net: dsa: mv88e6xxx: Enable CMODE config support for 6390X dt-binding: ptp: Add SoC compatibility strings for dte ptp clock NET: dwmac: Make dwmac reset unconditional net: Zero terminate ifr_name in dev_ifname(). wireless: wext: terminate ifr name coming from userspace netfilter: fix netfilter_net_init() return ... -
Kosuke Tatsukawa authored
balance-alb mode used to have transmit dynamic load balancing feature enabled by default. However, transmit dynamic load balancing no longer works in balance-alb after commit 8b426dc5 ("bonding: remove hardcoded value"). Both balance-tlb and balance-alb use the function bond_do_alb_xmit() to send packets. This function uses the parameter tlb_dynamic_lb. tlb_dynamic_lb used to have the default value of 1 for balance-alb, but now the value is set to 0 except in balance-tlb. Re-enable transmit dyanmic load balancing by initializing tlb_dynamic_lb for balance-alb similar to balance-tlb. Fixes: 8b426dc5 ("bonding: remove hardcoded value") Signed-off-by:
Kosuke Tatsukawa <tatsu@ab.jp.nec.com> Acked-by:
Andy Gospodarek <andy@greyhouse.net> Signed-off-by:
David S. Miller <davem@davemloft.net>
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Håkon Bugge authored
cp->cp_send_gen is treated as a normal variable, although it may be used by different threads. This is fixed by using {READ,WRITE}_ONCE when it is incremented and READ_ONCE when it is read outside the {acquire,release}_in_xmit protection. Normative reference from the Linux-Kernel Memory Model: Loads from and stores to shared (but non-atomic) variables should be protected with the READ_ONCE(), WRITE_ONCE(), and ACCESS_ONCE(). Clause 5.1.2.4/25 in the C standard is also relevant. Signed-off-by:Håkon Bugge <haakon.bugge@oracle.com> Reviewed-by:
Knut Omang <knut.omang@oracle.com> Acked-by:
Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by:
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Ganesh Goudar authored
print the versions of vpd and serial configuration file, flashed to adapter, and cleanup the relevant code. Signed-off-by:
Casey Leedom <leedom@chelsio.com> Signed-off-by:
Ganesh Goudar <ganeshgr@chelsio.com> Signed-off-by:
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Keerthy authored
Push the request_irq function to the end of probe so as to ensure all the required fields are populated in the event of an ISR getting executed right after requesting the irq. Currently while loading the crash kernel a crash was seen as soon as devm_request_threaded_irq was called. This was due to n->poll being NULL which is called as part of net_rx_action function. Suggested-by:
Sekhar Nori <nsekhar@ti.com> Signed-off-by:
Keerthy <j-keerthy@ti.com> Signed-off-by:
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Mahesh Bandewar authored
Net stack initialization currently initializes fib-trie after the first call to netdevice_notifier() call. In fact fib_trie initialization needs to happen before first rtnl_register(). It does not cause any problem since there are no devices UP at this moment, but trying to bring 'lo' UP at initialization would make this assumption wrong and exposes the issue. Fixes following crash Call Trace: ? alternate_node_alloc+0x76/0xa0 fib_table_insert+0x1b7/0x4b0 fib_magic.isra.17+0xea/0x120 fib_add_ifaddr+0x7b/0x190 fib_netdev_event+0xc0/0x130 register_netdevice_notifier+0x1c1/0x1d0 ip_fib_init+0x72/0x85 ip_rt_init+0x187/0x1e9 ip_init+0xe/0x1a inet_init+0x171/0x26c ? ipv4_offload_init+0x66/0x66 do_one_initcall+0x43/0x160 kernel_init_freeable+0x191/0x219 ? rest_init+0x80/0x80 kernel_init+0xe/0x150 ret_from_fork+0x22/0x30 Code: f6 46 23 04 74 86 4c 89 f7 e8 ae 45 01 00 49 89 c7 4d 85 ff 0f 85 7b ff ff ff 31 db eb 08 4c 89 ff e8 16 47 01 00 48 8b 44 24 38 <45> 8b 6e 14 4d 63 76 74 48 89 04 24 0f 1f 44 00 00 48 83 c4 08 RIP: kmem_cache_alloc+0xcf/0x1c0 RSP: ffff9b1500017c28 CR2: 0000000000000014 Fixes: 7b1a74fd ("[NETNS]: Refactor fib initialization so it can handle multiple namespaces.") Fixes: 7f9b8052 ("[IPV4]: fib hash|trie initialization") Signed-off-by:
Mahesh Bandewar <maheshb@google.com> Acked-by:
"Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by:
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WANG Cong authored
virtnet_set_mac_address() interprets mac address as struct sockaddr, but upper layer only allocates dev->addr_len which is ETH_ALEN + sizeof(sa_family_t) in this case. We lack a unified definition for mac address, so just fix the upper layer, this also allows drivers to interpret it to struct sockaddr freely. Reported-by:
David Ahern <dsahern@gmail.com> Signed-off-by:
Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by:
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Florian Fainelli authored
The BCM53125 entry was missing an arl_entries member which would basically prevent the ARL search from terminating properly. This switch has 4 ARL entries, so add that. Fixes: 1da6df85 ("net: dsa: b53: Implement ARL add/del/dump operations") Signed-off-by:
Florian Fainelli <f.fainelli@gmail.com> Reviewed-by:
Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by:
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David S. Miller authored
Daniel Borkmann says: ==================== BPF map value adjust fix First patch in the series is the actual fix and the remaining patches are just updates to selftests. ==================== Signed-off-by: -
Daniel Borkmann authored
Add a couple of more test cases to BPF selftests that are related to mixed signed and unsigned checks. Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Acked-by:
Alexei Starovoitov <ast@kernel.org> Signed-off-by:
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Edward Cree authored
These failed due to a bug in verifier bounds handling. Signed-off-by:
Edward Cree <ecree@solarflare.com> Acked-by:
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Daniel Borkmann authored
Fix the few existing test cases that used mixed signed/unsigned bounds and switch them only to one flavor. Reason why we need this is that proper boundaries cannot be derived from mixed tests. Signed-off-by:
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Daniel Borkmann authored
For the test_verifier case, it's quite hard to parse log level 2 to figure out what's causing an issue when used to log level 1. We do want to use bpf_verify_program() in order to simulate some of the tests with strict alignment. So just add an argument to pass the level and put it to 1 for test_verifier. Signed-off-by:
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Daniel Borkmann authored
Edward reported that there's an issue in min/max value bounds tracking when signed and unsigned compares both provide hints on limits when having unknown variables. E.g. a program such as the following should have been rejected: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff8a94cda93400 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+7 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = -1 10: (2d) if r1 > r2 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 11: (65) if r1 s> 0x1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 12: (0f) r0 += r1 13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=0,max_value=1 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 14: (b7) r0 = 0 15: (95) exit What happens is that in the first part ... 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = -1 10: (2d) if r1 > r2 goto pc+3 ... r1 carries an unsigned value, and is compared as unsigned against a register carrying an immediate. Verifier deduces in reg_set_min_max() that since the compare is unsigned and operation is greater than (>), that in the fall-through/false case, r1's minimum bound must be 0 and maximum bound must be r2. Latter is larger than the bound and thus max value is reset back to being 'invalid' aka BPF_REGISTER_MAX_RANGE. Thus, r1 state is now 'R1=inv,min_value=0'. The subsequent test ... 11: (65) if r1 s> 0x1 goto pc+2 ... is a signed compare of r1 with immediate value 1. Here, verifier deduces in reg_set_min_max() that since the compare is signed this time and operation is greater than (>), that in the fall-through/false case, we can deduce that r1's maximum bound must be 1, meaning with prior test, we result in r1 having the following state: R1=inv,min_value=0,max_value=1. Given that the actual value this holds is -8, the bounds are wrongly deduced. When this is being added to r0 which holds the map_value(_adj) type, then subsequent store access in above case will go through check_mem_access() which invokes check_map_access_adj(), that will then probe whether the map memory is in bounds based on the min_value and max_value as well as access size since the actual unknown value is min_value <= x <= max_value; commit fce366a9 ("bpf, verifier: fix alu ops against map_value{, _adj} register types") provides some more explanation on the semantics. It's worth to note in this context that in the current code, min_value and max_value tracking are used for two things, i) dynamic map value access via check_map_access_adj() and since commit 06c1c049 ("bpf: allow helpers access to variable memory") ii) also enforced at check_helper_mem_access() when passing a memory address (pointer to packet, map value, stack) and length pair to a helper and the length in this case is an unknown value defining an access range through min_value/max_value in that case. The min_value/max_value tracking is /not/ used in the direct packet access case to track ranges. However, the issue also affects case ii), for example, the following crafted program based on the same principle must be rejected as well: 0: (b7) r2 = 0 1: (bf) r3 = r10 2: (07) r3 += -512 3: (7a) *(u64 *)(r10 -16) = -8 4: (79) r4 = *(u64 *)(r10 -16) 5: (b7) r6 = -1 6: (2d) if r4 > r6 goto pc+5 R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 7: (65) if r4 s> 0x1 goto pc+4 R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0,max_value=1 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 8: (07) r4 += 1 9: (b7) r5 = 0 10: (6a) *(u16 *)(r10 -512) = 0 11: (85) call bpf_skb_load_bytes#26 12: (b7) r0 = 0 13: (95) exit Meaning, while we initialize the max_value stack slot that the verifier thinks we access in the [1,2] range, in reality we pass -7 as length which is interpreted as u32 in the helper. Thus, this issue is relevant also for the case of helper ranges. Resetting both bounds in check_reg_overflow() in case only one of them exceeds limits is also not enough as similar test can be created that uses values which are within range, thus also here learned min value in r1 is incorrect when mixed with later signed test to create a range: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff880ad081fa00 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+7 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = 2 10: (3d) if r2 >= r1 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 11: (65) if r1 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 12: (0f) r0 += r1 13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=3,max_value=4 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 14: (b7) r0 = 0 15: (95) exit This leaves us with two options for fixing this: i) to invalidate all prior learned information once we switch signed context, ii) to track min/max signed and unsigned boundaries separately as done in [0]. (Given latter introduces major changes throughout the whole verifier, it's rather net-next material, thus this patch follows option i), meaning we can derive bounds either from only signed tests or only unsigned tests.) There is still the case of adjust_reg_min_max_vals(), where we adjust bounds on ALU operations, meaning programs like the following where boundaries on the reg get mixed in context later on when bounds are merged on the dst reg must get rejected, too: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff89b2bf87ce00 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+6 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = 2 10: (3d) if r2 >= r1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 11: (b7) r7 = 1 12: (65) if r7 s> 0x0 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,max_value=0 R10=fp 13: (b7) r0 = 0 14: (95) exit from 12 to 15: R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,min_value=1 R10=fp 15: (0f) r7 += r1 16: (65) if r7 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 17: (0f) r0 += r7 18: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=4,max_value=4 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 19: (b7) r0 = 0 20: (95) exit Meaning, in adjust_reg_min_max_vals() we must also reset range values on the dst when src/dst registers have mixed signed/ unsigned derived min/max value bounds with one unbounded value as otherwise they can be added together deducing false boundaries. Once both boundaries are established from either ALU ops or compare operations w/o mixing signed/unsigned insns, then they can safely be added to other regs also having both boundaries established. Adding regs with one unbounded side to a map value where the bounded side has been learned w/o mixing ops is possible, but the resulting map value won't recover from that, meaning such op is considered invalid on the time of actual access. Invalid bounds are set on the dst reg in case i) src reg, or ii) in case dst reg already had them. The only way to recover would be to perform i) ALU ops but only 'add' is allowed on map value types or ii) comparisons, but these are disallowed on pointers in case they span a range. This is fine as only BPF_JEQ and BPF_JNE may be performed on PTR_TO_MAP_VALUE_OR_NULL registers which potentially turn them into PTR_TO_MAP_VALUE type depending on the branch, so only here min/max value cannot be invalidated for them. In terms of state pruning, value_from_signed is considered as well in states_equal() when dealing with adjusted map values. With regards to breaking existing programs, there is a small risk, but use-cases are rather quite narrow where this could occur and mixing compares probably unlikely. Joint work with Josef and Edward. [0] https://lists.iovisor.org/pipermail/iovisor-dev/2017-June/000822.html Fixes: 48461135 ("bpf: allow access into map value arrays") Reported-by:
Josef Bacik <jbacik@fb.com> Signed-off-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds authored
Pull power management fixes from Rafael Wysocki: "These are two stable-candidate fixes for the intel_pstate driver and the generic power domains (genpd) framework. Specifics: - Fix the average CPU load computations in the intel_pstate driver on Knights Landing (Xeon Phi) processors that require an extra factor to compensate for a rate change differences between the TSC and MPERF which is missing (Srinivas Pandruvada). - Fix an initialization ordering issue in the generic power domains (genpd) framework (Sudeep Holla)" * tag 'pm-4.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if present cpufreq: intel_pstate: Correct the busy calculation for KNL
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