lwn.git/net/sched/ematch.c, branch v5.11-rc4

net: sched: kerneldoc fixes

2020-07-14T00:20:40+00:00

Simple fixes which require no deep knowledge of the code. Cc: Jamal Hadi Salim Cc: Cong Wang Cc: Jiri Pirko Signed-off-by: Andrew Lunn Signed-off-by: David S. Miller

net_sched: ematch: reject invalid TCF_EM_SIMPLE

2020-01-27T09:55:26+00:00

It is possible for malicious userspace to set TCF_EM_SIMPLE bit even for matches that should not have this bit set. This can fool two places using tcf_em_is_simple() 1) tcf_em_tree_destroy() -> memory leak of em->data if ops->destroy() is NULL 2) tcf_em_tree_dump() wrongly report/leak 4 low-order bytes of a kernel pointer. BUG: memory leak unreferenced object 0xffff888121850a40 (size 32): comm "syz-executor927", pid 7193, jiffies 4294941655 (age 19.840s) hex dump (first 32 bytes): 00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000f67036ea>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] [<00000000f67036ea>] slab_post_alloc_hook mm/slab.h:586 [inline] [<00000000f67036ea>] slab_alloc mm/slab.c:3320 [inline] [<00000000f67036ea>] __do_kmalloc mm/slab.c:3654 [inline] [<00000000f67036ea>] __kmalloc_track_caller+0x165/0x300 mm/slab.c:3671 [<00000000fab0cc8e>] kmemdup+0x27/0x60 mm/util.c:127 [<00000000d9992e0a>] kmemdup include/linux/string.h:453 [inline] [<00000000d9992e0a>] em_nbyte_change+0x5b/0x90 net/sched/em_nbyte.c:32 [<000000007e04f711>] tcf_em_validate net/sched/ematch.c:241 [inline] [<000000007e04f711>] tcf_em_tree_validate net/sched/ematch.c:359 [inline] [<000000007e04f711>] tcf_em_tree_validate+0x332/0x46f net/sched/ematch.c:300 [<000000007a769204>] basic_set_parms net/sched/cls_basic.c:157 [inline] [<000000007a769204>] basic_change+0x1d7/0x5f0 net/sched/cls_basic.c:219 [<00000000e57a5997>] tc_new_tfilter+0x566/0xf70 net/sched/cls_api.c:2104 [<0000000074b68559>] rtnetlink_rcv_msg+0x3b2/0x4b0 net/core/rtnetlink.c:5415 [<00000000b7fe53fb>] netlink_rcv_skb+0x61/0x170 net/netlink/af_netlink.c:2477 [<00000000e83a40d0>] rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442 [<00000000d62ba933>] netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] [<00000000d62ba933>] netlink_unicast+0x223/0x310 net/netlink/af_netlink.c:1328 [<0000000088070f72>] netlink_sendmsg+0x2c0/0x570 net/netlink/af_netlink.c:1917 [<00000000f70b15ea>] sock_sendmsg_nosec net/socket.c:639 [inline] [<00000000f70b15ea>] sock_sendmsg+0x54/0x70 net/socket.c:659 [<00000000ef95a9be>] ____sys_sendmsg+0x2d0/0x300 net/socket.c:2330 [<00000000b650f1ab>] ___sys_sendmsg+0x8a/0xd0 net/socket.c:2384 [<0000000055bfa74a>] __sys_sendmsg+0x80/0xf0 net/socket.c:2417 [<000000002abac183>] __do_sys_sendmsg net/socket.c:2426 [inline] [<000000002abac183>] __se_sys_sendmsg net/socket.c:2424 [inline] [<000000002abac183>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2424 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: syzbot+03c4738ed29d5d366ddf@syzkaller.appspotmail.com Cc: Cong Wang Acked-by: Cong Wang Signed-off-by: David S. Miller

net_sched: fix datalen for ematch

2020-01-23T20:34:42+00:00

syzbot reported an out-of-bound access in em_nbyte. As initially analyzed by Eric, this is because em_nbyte sets its own em->datalen in em_nbyte_change() other than the one specified by user, but this value gets overwritten later by its caller tcf_em_validate(). We should leave em->datalen untouched to respect their choices. I audit all the in-tree ematch users, all of those implement ->change() set em->datalen, so we can just avoid setting it twice in this case. Reported-and-tested-by: syzbot+5af9a90dad568aa9f611@syzkaller.appspotmail.com Reported-by: syzbot+2f07903a5b05e7f36410@syzkaller.appspotmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: Eric Dumazet Signed-off-by: Cong Wang Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

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 as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

netlink: make validation more configurable for future strictness

2019-04-27T21:07:21+00:00

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 Signed-off-by: David S. Miller

netlink: make nla_nest_start() add NLA_F_NESTED flag

2019-04-27T21:03:44+00:00

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 Acked-by: Jiri Pirko Acked-by: David Ahern Signed-off-by: David S. Miller

net: sched: ematch: obtain net pointer from blocks

2017-10-16T20:00:40+00:00

Instead of using tp->q, use block to get the net pointer. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

netlink: pass extended ACK struct to parsing functions

2017-04-13T17:58:22+00:00

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 Signed-off-by: David S. Miller

ematch: Fix auto-loading of ematch modules.

2015-02-20T20:30:56+00:00

In tcf_em_validate(), after calling request_module() to load the kind-specific module, set em->ops to NULL before returning -EAGAIN, so that module_put() is not called again by tcf_em_tree_destroy(). Signed-off-by: Ignacy Gawędzki Acked-by: Cong Wang Signed-off-by: David S. Miller

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

2014-10-08T20:22:22+00:00