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2022-07-11netfilter: nf_conntrack: use rcu accessors where neededFlorian Westphal1-3/+7
Sparse complains about direct access to the 'helper' and timeout members. Both have __rcu annotation, so use the accessors. xt_CT is fine, accesses occur before the structure is visible to other cpus. Switch to rcu accessors there as well to reduce noise. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-07Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-2/+6
Bug fixes overlapping feature additions and refactoring, mostly. Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-02netfilter: nfnetlink_cthelper: hit EBUSY on updates if size mismatchesPablo Neira Ayuso1-2/+6
The private helper data size cannot be updated. However, updates that contain NFCTH_PRIV_DATA_LEN might bogusly hit EBUSY even if the size is the same. Fixes: 12f7a505331e ("netfilter: add user-space connection tracking helper infrastructure") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-05-29netfilter: use nfnetlink_unicast()Pablo Neira Ayuso1-7/+3
Replace netlink_unicast() calls by nfnetlink_unicast() which already deals with translating EAGAIN to ENOBUFS as the nfnetlink core expects. nfnetlink_unicast() calls nlmsg_unicast() which returns zero in case of success, otherwise the netlink core function netlink_rcv_skb() turns err > 0 into an acknowlegment. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-26netfilter: nfnetlink: consolidate callback typesPablo Neira Ayuso1-9/+18
Add enum nfnl_callback_type to identify the callback type to provide one single callback. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-04-26netfilter: nfnetlink: add struct nfnl_info and pass it to callbacksPablo Neira Ayuso1-18/+12
Add a new structure to reduce callback footprint and to facilite extensions of the nfnetlink callback interface in the future. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-03-31netfilter: add helper function to set up the nfnetlink header and use itPablo Neira Ayuso1-8/+3
This patch adds a helper function to set up the netlink and nfnetlink headers. Update existing codebase to use it. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-11-16treewide: rename nla_strlcpy to nla_strscpy.Francis Laniel1-2/+2
Calls to nla_strlcpy are now replaced by calls to nla_strscpy which is the new name of this function. Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-05-25netfilter: nfnetlink_cthelper: unbreak userspace helper supportPablo Neira Ayuso1-1/+2
Restore helper data size initialization and fix memcopy of the helper data size. Fixes: 157ffffeb5dc ("netfilter: nfnetlink_cthelper: reject too large userspace allocation requests") Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-03-04netfilter: cthelper: add missing attribute validation for cthelperJakub Kicinski1-0/+2
Add missing attribute validation for cthelper to the netlink policy. Fixes: 12f7a505331e ("netfilter: add user-space connection tracking helper infrastructure") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-12-09treewide: Use sizeof_field() macroPankaj Bharadiya1-1/+1
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except at places where these are defined. Later patches will remove the unused definition of FIELD_SIZEOF(). This patch is generated using following script: EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h" git grep -l -e "\bFIELD_SIZEOF\b" | while read file; do if [[ "$file" =~ $EXCLUDE_FILES ]]; then continue fi sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file; done Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com> Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: David Miller <davem@davemloft.net> # for net
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 77Thomas Gleixner1-4/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation or any later at your option extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 5 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520075210.769496418@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27netlink: make validation more configurable for future strictnessJohannes Berg1-10/+12
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27netlink: make nla_nest_start() add NLA_F_NESTED flagMichal Kubecek1-4/+3
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most netlink based interfaces (including recently added ones) are still not setting it in kernel generated messages. Without the flag, message parsers not aware of attribute semantics (e.g. wireshark dissector or libmnl's mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display the structure of their contents. Unfortunately we cannot just add the flag everywhere as there may be userspace applications which check nlattr::nla_type directly rather than through a helper masking out the flags. Therefore the patch renames nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start() as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually are rewritten to use nla_nest_start(). Except for changes in include/net/netlink.h, the patch was generated using this semantic patch: @@ expression E1, E2; @@ -nla_nest_start(E1, E2) +nla_nest_start_noflag(E1, E2) @@ expression E1, E2; @@ -nla_nest_start_noflag(E1, E2 | NLA_F_NESTED) +nla_nest_start(E1, E2) Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-12treewide: kzalloc() -> kcalloc()Kees Cook1-2/+3
The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-05-24netfilter: provide correct argument to nla_strlcpy()Eric Dumazet1-2/+2
Recent patch forgot to remove nla_data(), upsetting syzkaller a bit. BUG: KASAN: slab-out-of-bounds in nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 Read of size 1 at addr ffff8801ad1f4fdd by task syz-executor189/4509 CPU: 1 PID: 4509 Comm: syz-executor189 Not tainted 4.17.0-rc6+ #62 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 nfnl_acct_new+0x574/0xc50 net/netfilter/nfnetlink_acct.c:118 nfnetlink_rcv_msg+0xdb5/0xff0 net/netfilter/nfnetlink.c:212 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2448 nfnetlink_rcv+0x1fe/0x1ba0 net/netfilter/nfnetlink.c:513 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x58b/0x740 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x9f0/0xfa0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 sock_write_iter+0x35a/0x5a0 net/socket.c:908 call_write_iter include/linux/fs.h:1784 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x64d/0x960 fs/read_write.c:487 vfs_write+0x1f8/0x560 fs/read_write.c:549 ksys_write+0xf9/0x250 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 Fixes: 4e09fc873d92 ("netfilter: prefer nla_strlcpy for dealing with NLA_STRING attributes") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Florian Westphal <fw@strlen.de> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-08netfilter: prefer nla_strlcpy for dealing with NLA_STRING attributesFlorian Westphal1-3/+4
fixes these warnings: 'nfnl_cthelper_create' at net/netfilter/nfnetlink_cthelper.c:237:2, 'nfnl_cthelper_new' at net/netfilter/nfnetlink_cthelper.c:450:9: ./include/linux/string.h:246:9: warning: '__builtin_strncpy' specified bound 16 equals destination size [-Wstringop-truncation] return __builtin_strncpy(p, q, size); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Moreover, strncpy assumes null-terminated source buffers, but thats not the case here. Unlike strlcpy, nla_strlcpy *does* pad the destination buffer while also considering nla attribute size. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-03-20netfilter: nfnetlink_cthelper: Remove VLA usageGustavo A. R. Silva1-8/+17
In preparation to enabling -Wvla, remove VLA and replace it with dynamic memory allocation. >From a security viewpoint, the use of Variable Length Arrays can be a vector for stack overflow attacks. Also, in general, as the code evolves it is easy to lose track of how big a VLA can get. Thus, we can end up having segfaults that are hard to debug. Also, fixed as part of the directive to remove all VLAs from the kernel: https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-12-04netfilter: nfnetlink_cthelper: Add missing permission checksKevin Cernekee1-0/+10
The capability check in nfnetlink_rcv() verifies that the caller has CAP_NET_ADMIN in the namespace that "owns" the netlink socket. However, nfnl_cthelper_list is shared by all net namespaces on the system. An unprivileged user can create user and net namespaces in which he holds CAP_NET_ADMIN to bypass the netlink_net_capable() check: $ nfct helper list nfct v1.4.4: netlink error: Operation not permitted $ vpnns -- nfct helper list { .name = ftp, .queuenum = 0, .l3protonum = 2, .l4protonum = 6, .priv_data_len = 24, .status = enabled, }; Add capable() checks in nfnetlink_cthelper, as this is cleaner than trying to generalize the solution. Signed-off-by: Kevin Cernekee <cernekee@chromium.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-06-19netfilter: nfnetlink: extended ACK reportingPablo Neira Ayuso1-3/+6
Pass down struct netlink_ext_ack as parameter to all of our nfnetlink subsystem callbacks, so we can work on follow up patches to provide finer grain error reporting using the new infrastructure that 2d4bc93368f5 ("netlink: extended ACK reporting") provides. No functional change, just pass down this new object to callbacks. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-15netfilter: nfnl_cthelper: reject del request if helper obj is in useLiping Zhang1-6/+11
We can still delete the ct helper even if it is in use, this will cause a use-after-free error. In more detail, I mean: # nfct helper add ssdp inet udp # iptables -t raw -A OUTPUT -p udp -j CT --helper ssdp # nfct helper delete ssdp //--> oops, succeed! BUG: unable to handle kernel paging request at 000026ca IP: 0x26ca [...] Call Trace: ? ipv4_helper+0x62/0x80 [nf_conntrack_ipv4] nf_hook_slow+0x21/0xb0 ip_output+0xe9/0x100 ? ip_fragment.constprop.54+0xc0/0xc0 ip_local_out+0x33/0x40 ip_send_skb+0x16/0x80 udp_send_skb+0x84/0x240 udp_sendmsg+0x35d/0xa50 So add reference count to fix this issue, if ct helper is used by others, reject the delete request. Apply this patch: # nfct helper delete ssdp nfct v1.4.3: netlink error: Device or resource busy Signed-off-by: Liping Zhang <zlpnobody@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller1-3/+15
Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following patchset contains Netfilter updates for your net-next tree. A large bunch of code cleanups, simplify the conntrack extension codebase, get rid of the fake conntrack object, speed up netns by selective synchronize_net() calls. More specifically, they are: 1) Check for ct->status bit instead of using nfct_nat() from IPVS and Netfilter codebase, patch from Florian Westphal. 2) Use kcalloc() wherever possible in the IPVS code, from Varsha Rao. 3) Simplify FTP IPVS helper module registration path, from Arushi Singhal. 4) Introduce nft_is_base_chain() helper function. 5) Enforce expectation limit from userspace conntrack helper, from Gao Feng. 6) Add nf_ct_remove_expect() helper function, from Gao Feng. 7) NAT mangle helper function return boolean, from Gao Feng. 8) ctnetlink_alloc_expect() should only work for conntrack with helpers, from Gao Feng. 9) Add nfnl_msg_type() helper function to nfnetlink to build the netlink message type. 10) Get rid of unnecessary cast on void, from simran singhal. 11) Use seq_puts()/seq_putc() instead of seq_printf() where possible, also from simran singhal. 12) Use list_prev_entry() from nf_tables, from simran signhal. 13) Remove unnecessary & on pointer function in the Netfilter and IPVS code. 14) Remove obsolete comment on set of rules per CPU in ip6_tables, no longer true. From Arushi Singhal. 15) Remove duplicated nf_conntrack_l4proto_udplite4, from Gao Feng. 16) Remove unnecessary nested rcu_read_lock() in __nf_nat_decode_session(). Code running from hooks are already guaranteed to run under RCU read side. 17) Remove deadcode in nf_tables_getobj(), from Aaron Conole. 18) Remove double assignment in nf_ct_l4proto_pernet_unregister_one(), also from Aaron. 19) Get rid of unsed __ip_set_get_netlink(), from Aaron Conole. 20) Don't propagate NF_DROP error to userspace via ctnetlink in __nf_nat_alloc_null_binding() function, from Gao Feng. 21) Revisit nf_ct_deliver_cached_events() to remove unnecessary checks, from Gao Feng. 22) Kill the fake untracked conntrack objects, use ctinfo instead to annotate a conntrack object is untracked, from Florian Westphal. 23) Remove nf_ct_is_untracked(), now obsolete since we have no conntrack template anymore, from Florian. 24) Add event mask support to nft_ct, also from Florian. 25) Move nf_conn_help structure to include/net/netfilter/nf_conntrack_helper.h. 26) Add a fixed 32 bytes scratchpad area for conntrack helpers. Thus, we don't deal with variable conntrack extensions anymore. Make sure userspace conntrack helper doesn't go over that size. Remove variable size ct extension infrastructure now this code got no more clients. From Florian Westphal. 27) Restore offset and length of nf_ct_ext structure to 8 bytes now that wraparound is not possible any longer, also from Florian. 28) Allow to get rid of unassured flows under stress in conntrack, this applies to DCCP, SCTP and TCP protocols, from Florian. 29) Shrink size of nf_conntrack_ecache structure, from Florian. 30) Use TCP_MAX_WSCALE instead of hardcoded 14 in TCP tracker, from Gao Feng. 31) Register SYNPROXY hooks on demand, from Florian Westphal. 32) Use pernet hook whenever possible, instead of global hook registration, from Florian Westphal. 33) Pass hook structure to ebt_register_table() to consolidate some infrastructure code, from Florian Westphal. 34) Use consume_skb() and return NF_STOLEN, instead of NF_DROP in the SYNPROXY code, to make sure device stats are not fooled, patch from Gao Feng. 35) Remove NF_CT_EXT_F_PREALLOC this kills quite some code that we don't need anymore if we just select a fixed size instead of expensive runtime time calculation of this. From Florian. 36) Constify nf_ct_extend_register() and nf_ct_extend_unregister(), from Florian. 37) Simplify nf_ct_ext_add(), this kills nf_ct_ext_create(), from Florian. 38) Attach NAT extension on-demand from masquerade and pptp helper path, from Florian. 39) Get rid of useless ip_vs_set_state_timeout(), from Aaron Conole. 40) Speed up netns by selective calls of synchronize_net(), from Florian Westphal. 41) Silence stack size warning gcc in 32-bit arch in snmp helper, from Florian. 42) Inconditionally call nf_ct_ext_destroy(), even if we have no extensions, to deal with the NF_NAT_MANIP_SRC case. Patch from Liping Zhang. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-19netfilter: nfnetlink_cthelper: reject too large userspace allocation requestsFlorian Westphal1-2/+8
Userspace should not abuse the kernel to store large amounts of data, reject requests larger than the private area can accommodate. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg1-5/+7
Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-07netfilter: Add nfnl_msg_type() helper functionPablo Neira Ayuso1-1/+1
Add and use nfnl_msg_type() function to replace opencoded nfnetlink message type. I suggested this change, Arushi Singhal made an initial patch to address this but was missing several spots. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-06netfilter: expect: Make sure the max_expected limit is effectiveGao Feng1-0/+6
Because the type of expecting, the member of nf_conn_help, is u8, it would overflow after reach U8_MAX(255). So it doesn't work when we configure the max_expected exceeds 255 with expect policy. Now add the check for max_expected. Return the -EINVAL when it exceeds the limit. Signed-off-by: Gao Feng <fgao@ikuai8.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-27netfilter: nfnl_cthelper: fix a race when walk the nf_ct_helper_hash tableLiping Zhang1-96/+81
The nf_ct_helper_hash table is protected by nf_ct_helper_mutex, while nfct_helper operation is protected by nfnl_lock(NFNL_SUBSYS_CTHELPER). So it's possible that one CPU is walking the nf_ct_helper_hash for cthelper add/get/del, another cpu is doing nf_conntrack_helpers_unregister at the same time. This is dangrous, and may cause use after free error. Note, delete operation will flush all cthelpers added via nfnetlink, so using rcu to do protect is not easy. Now introduce a dummy list to record all the cthelpers added via nfnetlink, then we can walk the dummy list instead of walking the nf_ct_helper_hash. Also, keep nfnl_cthelper_dump_table unchanged, it may be invoked without nfnl_lock(NFNL_SUBSYS_CTHELPER) held. Signed-off-by: Liping Zhang <zlpnobody@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-22netfilter: nfnl_cthelper: Fix memory leakJeffy Chen1-3/+9
We have memory leaks of nf_conntrack_helper & expect_policy. Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-03-22netfilter: nfnl_cthelper: fix runtime expectation policy updatesPablo Neira Ayuso1-2/+84
We only allow runtime updates of expectation policies for timeout and maximum number of expectations, otherwise reject the update. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Liping Zhang <zlpnobody@gmail.com>
2017-03-21netfilter: nfnl_cthelper: fix incorrect helper->expect_class_maxLiping Zhang1-9/+11
The helper->expect_class_max must be set to the total number of expect_policy minus 1, since we will use the statement "if (class > helper->expect_class_max)" to validate the CTA_EXPECT_CLASS attr in ctnetlink_alloc_expect. So for compatibility, set the helper->expect_class_max to the NFCTH_POLICY_SET_NUM attr's value minus 1. Also: it's invalid when the NFCTH_POLICY_SET_NUM attr's value is zero. 1. this will result "expect_policy = kzalloc(0, GFP_KERNEL);"; 2. we cannot set the helper->expect_class_max to a proper value. So if nla_get_be32(tb[NFCTH_POLICY_SET_NUM]) is zero, report -EINVAL to the userspace. Signed-off-by: Liping Zhang <zlpnobody@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-27scripts/spelling.txt: add "an user" pattern and fix typo instancesMasahiro Yamada1-1/+1
Fix typos and add the following to the scripts/spelling.txt: an user||a user an userspace||a userspace I also added "userspace" to the list since it is a common word in Linux. I found some instances for "an userfaultfd", but I did not add it to the list. I felt it is endless to find words that start with "user" such as "userland" etc., so must draw a line somewhere. Link: http://lkml.kernel.org/r/1481573103-11329-4-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-24netfilter: Remove explicit rcu_read_lock in nf_hook_slowAaron Conole1-1/+1
All of the callers of nf_hook_slow already hold the rcu_read_lock, so this cleanup removes the recursive call. This is just a cleanup, as the locking code gracefully handles this situation. Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-12-28netfilter: nfnetlink: pass down netns pointer to call() and call_rcu()Pablo Neira Ayuso1-9/+9
Adapt callsites to avoid recurrent lookup of the netns pointer. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-03-12netfilter: Zero the tuple in nfnl_cthelper_parse_tuple()Ian Wilson1-0/+3
nfnl_cthelper_parse_tuple() is called from nfnl_cthelper_new(), nfnl_cthelper_get() and nfnl_cthelper_del(). In each case they pass a pointer to an nf_conntrack_tuple data structure local variable: struct nf_conntrack_tuple tuple; ... ret = nfnl_cthelper_parse_tuple(&tuple, tb[NFCTH_TUPLE]); The problem is that this local variable is not initialized, and nfnl_cthelper_parse_tuple() only initializes two fields: src.l3num and dst.protonum. This leaves all other fields with undefined values based on whatever is on the stack: tuple->src.l3num = ntohs(nla_get_be16(tb[NFCTH_TUPLE_L3PROTONUM])); tuple->dst.protonum = nla_get_u8(tb[NFCTH_TUPLE_L4PROTONUM]); The symptom observed was that when the rpc and tns helpers were added then traffic to port 1536 was being sent to user-space. Signed-off-by: Ian Wilson <iwilson@brocade.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-01-05netfilter: nfnetlink_cthelper: Remove 'const' and '&' to avoid warningsChen Gang1-2/+2
The related code can be simplified, and also can avoid related warnings (with allmodconfig under parisc): CC [M] net/netfilter/nfnetlink_cthelper.o net/netfilter/nfnetlink_cthelper.c: In function ‘nfnl_cthelper_from_nlattr’: net/netfilter/nfnetlink_cthelper.c:97:9: warning: passing argument 1 o ‘memcpy’ discards ‘const’ qualifier from pointer target type [-Wdiscarded-array-qualifiers] memcpy(&help->data, nla_data(attr), help->helper->data_len); ^ In file included from include/linux/string.h:17:0, from include/uapi/linux/uuid.h:25, from include/linux/uuid.h:23, from include/linux/mod_devicetable.h:12, from ./arch/parisc/include/asm/hardware.h:4, from ./arch/parisc/include/asm/processor.h:15, from ./arch/parisc/include/asm/spinlock.h:6, from ./arch/parisc/include/asm/atomic.h:21, from include/linux/atomic.h:4, from ./arch/parisc/include/asm/bitops.h:12, from include/linux/bitops.h:36, from include/linux/kernel.h:10, from include/linux/list.h:8, from include/linux/module.h:9, from net/netfilter/nfnetlink_cthelper.c:11: ./arch/parisc/include/asm/string.h:8:8: note: expected ‘void *’ but argument is of type ‘const char (*)[]’ void * memcpy(void * dest,const void *src,size_t count); ^ Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@soleta.eu>
2013-06-20netfilter: check return code from nla_parse_testedDaniel Borkmann1-4/+12
These are the only calls under net/ that do not check nla_parse_nested() for its error code, but simply continue execution. If parsing of netlink attributes fails, we should return with an error instead of continuing. In nearly all of these calls we have a policy attached, that is being type verified during nla_parse_nested(), which we would miss checking for otherwise. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-02-27hlist: drop the node parameter from iteratorsSasha Levin1-10/+7
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-24netfilter: nf_ct_ftp: add sequence tracking pickup facility for injected entriesPablo Neira Ayuso1-0/+3
This patch allows the FTP helper to pickup the sequence tracking from the first packet seen. This is useful to fix the breakage of the first FTP command after the failover while using conntrackd to synchronize states. The seq_aft_nl_num field in struct nf_ct_ftp_info has been shrinked to 16-bits (enough for what it does), so we can use the remaining 16-bits to store the flags while using the same size for the private FTP helper data. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-10netlink: Rename pid to portid to avoid confusionEric W. Biederman1-6/+6
It is a frequent mistake to confuse the netlink port identifier with a process identifier. Try to reduce this confusion by renaming fields that hold port identifiers portid instead of pid. I have carefully avoided changing the structures exported to userspace to avoid changing the userspace API. I have successfully built an allyesconfig kernel with this change. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-20netfilter: sparse endian fixesPatrick McHardy1-1/+1
Fix a couple of endian annotation in net/netfilter: net/netfilter/nfnetlink_acct.c:82:30: warning: cast to restricted __be64 net/netfilter/nfnetlink_acct.c:86:30: warning: cast to restricted __be64 net/netfilter/nfnetlink_cthelper.c:77:28: warning: cast to restricted __be16 net/netfilter/xt_NFQUEUE.c:46:16: warning: restricted __be32 degrades to integer net/netfilter/xt_NFQUEUE.c:60:34: warning: restricted __be32 degrades to integer net/netfilter/xt_NFQUEUE.c:68:34: warning: restricted __be32 degrades to integer net/netfilter/xt_osf.c:272:55: warning: cast to restricted __be16 Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-16netfilter: add user-space connection tracking helper infrastructurePablo Neira Ayuso1-0/+672
There are good reasons to supports helpers in user-space instead: * Rapid connection tracking helper development, as developing code in user-space is usually faster. * Reliability: A buggy helper does not crash the kernel. Moreover, we can monitor the helper process and restart it in case of problems. * Security: Avoid complex string matching and mangling in kernel-space running in privileged mode. Going further, we can even think about running user-space helpers as a non-root process. * Extensibility: It allows the development of very specific helpers (most likely non-standard proprietary protocols) that are very likely not to be accepted for mainline inclusion in the form of kernel-space connection tracking helpers. This patch adds the infrastructure to allow the implementation of user-space conntrack helpers by means of the new nfnetlink subsystem `nfnetlink_cthelper' and the existing queueing infrastructure (nfnetlink_queue). I had to add the new hook NF_IP6_PRI_CONNTRACK_HELPER to register ipv[4|6]_helper which results from splitting ipv[4|6]_confirm into two pieces. This change is required not to break NAT sequence adjustment and conntrack confirmation for traffic that is enqueued to our user-space conntrack helpers. Basic operation, in a few steps: 1) Register user-space helper by means of `nfct': nfct helper add ftp inet tcp [ It must be a valid existing helper supported by conntrack-tools ] 2) Add rules to enable the FTP user-space helper which is used to track traffic going to TCP port 21. For locally generated packets: iptables -I OUTPUT -t raw -p tcp --dport 21 -j CT --helper ftp For non-locally generated packets: iptables -I PREROUTING -t raw -p tcp --dport 21 -j CT --helper ftp 3) Run the test conntrackd in helper mode (see example files under doc/helper/conntrackd.conf conntrackd 4) Generate FTP traffic going, if everything is OK, then conntrackd should create expectations (you can check that with `conntrack': conntrack -E expect [NEW] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp [DESTROY] 301 proto=6 src=192.168.1.136 dst=130.89.148.12 sport=0 dport=54037 mask-src=255.255.255.255 mask-dst=255.255.255.255 sport=0 dport=65535 master-src=192.168.1.136 master-dst=130.89.148.12 sport=57127 dport=21 class=0 helper=ftp This confirms that our test helper is receiving packets including the conntrack information, and adding expectations in kernel-space. The user-space helper can also store its private tracking information in the conntrack structure in the kernel via the CTA_HELP_INFO. The kernel will consider this a binary blob whose layout is unknown. This information will be included in the information that is transfered to user-space via glue code that integrates nfnetlink_queue and ctnetlink. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>