bf63ac73b3
Kelly reported the following crash: IP: [<ffffffff817a993d>] tcf_action_exec+0x46/0x90 PGD 3009067 PUD 300c067 PMD 11ff30067 PTE 800000011634b060 Oops: 0000 [#1] SMP DEBUG_PAGEALLOC CPU: 1 PID: 639 Comm: dhclient Not tainted 3.15.0-rc4+ #342 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff8801169ecd00 ti: ffff8800d21b8000 task.ti: ffff8800d21b8000 RIP: 0010:[<ffffffff817a993d>] [<ffffffff817a993d>] tcf_action_exec+0x46/0x90 RSP: 0018:ffff8800d21b9b90 EFLAGS: 00010283 RAX: 00000000ffffffff RBX: ffff88011634b8e8 RCX: ffff8800cf7133d8 RDX: ffff88011634b900 RSI: ffff8800cf7133e0 RDI: ffff8800d210f840 RBP: ffff8800d21b9bb0 R08: ffffffff8287bf60 R09: 0000000000000001 R10: ffff8800d2b22b24 R11: 0000000000000001 R12: ffff8800d210f840 R13: ffff8800d21b9c50 R14: ffff8800cf7133e0 R15: ffff8800cad433d8 FS: 00007f49723e1840(0000) GS:ffff88011a800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff88011634b8f0 CR3: 00000000ce469000 CR4: 00000000000006e0 Stack: ffff8800d2170188 ffff8800d210f840 ffff8800d2171b90 0000000000000000 ffff8800d21b9be8 ffffffff817c55bb ffff8800d21b9c50 ffff8800d2171b90 ffff8800d210f840 ffff8800d21b0300 ffff8800d21b9c50 ffff8800d21b9c18 Call Trace: [<ffffffff817c55bb>] tcindex_classify+0x88/0x9b [<ffffffff817a7f7d>] tc_classify_compat+0x3e/0x7b [<ffffffff817a7fdf>] tc_classify+0x25/0x9f [<ffffffff817b0e68>] htb_enqueue+0x55/0x27a [<ffffffff817b6c2e>] dsmark_enqueue+0x165/0x1a4 [<ffffffff81775642>] __dev_queue_xmit+0x35e/0x536 [<ffffffff8177582a>] dev_queue_xmit+0x10/0x12 [<ffffffff818f8ecd>] packet_sendmsg+0xb26/0xb9a [<ffffffff810b1507>] ? __lock_acquire+0x3ae/0xdf3 [<ffffffff8175cf08>] __sock_sendmsg_nosec+0x25/0x27 [<ffffffff8175d916>] sock_aio_write+0xd0/0xe7 [<ffffffff8117d6b8>] do_sync_write+0x59/0x78 [<ffffffff8117d84d>] vfs_write+0xb5/0x10a [<ffffffff8117d96a>] SyS_write+0x49/0x7f [<ffffffff8198e212>] system_call_fastpath+0x16/0x1b This is because we memcpy struct tcindex_filter_result which contains struct tcf_exts, obviously struct list_head can not be simply copied. This is a regression introduced by commit33be627159
(net_sched: act: use standard struct list_head). It's not very easy to fix it as the code is a mess: if (old_r) memcpy(&cr, r, sizeof(cr)); else { memset(&cr, 0, sizeof(cr)); tcf_exts_init(&cr.exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE); } ... tcf_exts_change(tp, &cr.exts, &e); ... memcpy(r, &cr, sizeof(cr)); the above code should equal to: tcindex_filter_result_init(&cr); if (old_r) cr.res = r->res; ... if (old_r) tcf_exts_change(tp, &r->exts, &e); else tcf_exts_change(tp, &cr.exts, &e); ... r->res = cr.res; after this change, since there is no need to copy struct tcf_exts. And it also fixes other places zero'ing struct's contains struct tcf_exts. Fixes: commit33be627159
(net_sched: act: use standard struct list_head) Reported-by: Kelly Anderson <kelly@xilka.com> Tested-by: Kelly Anderson <kelly@xilka.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
519 lines
12 KiB
C
519 lines
12 KiB
C
/*
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* net/sched/cls_tcindex.c Packet classifier for skb->tc_index
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*
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* Written 1998,1999 by Werner Almesberger, EPFL ICA
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*/
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <net/act_api.h>
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#include <net/netlink.h>
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#include <net/pkt_cls.h>
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/*
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* Passing parameters to the root seems to be done more awkwardly than really
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* necessary. At least, u32 doesn't seem to use such dirty hacks. To be
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* verified. FIXME.
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*/
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#define PERFECT_HASH_THRESHOLD 64 /* use perfect hash if not bigger */
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#define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */
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struct tcindex_filter_result {
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struct tcf_exts exts;
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struct tcf_result res;
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};
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struct tcindex_filter {
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u16 key;
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struct tcindex_filter_result result;
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struct tcindex_filter *next;
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};
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struct tcindex_data {
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struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
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struct tcindex_filter **h; /* imperfect hash; only used if !perfect;
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NULL if unused */
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u16 mask; /* AND key with mask */
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int shift; /* shift ANDed key to the right */
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int hash; /* hash table size; 0 if undefined */
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int alloc_hash; /* allocated size */
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int fall_through; /* 0: only classify if explicit match */
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};
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static inline int
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tcindex_filter_is_set(struct tcindex_filter_result *r)
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{
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return tcf_exts_is_predicative(&r->exts) || r->res.classid;
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}
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static struct tcindex_filter_result *
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tcindex_lookup(struct tcindex_data *p, u16 key)
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{
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struct tcindex_filter *f;
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if (p->perfect)
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return tcindex_filter_is_set(p->perfect + key) ?
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p->perfect + key : NULL;
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else if (p->h) {
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for (f = p->h[key % p->hash]; f; f = f->next)
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if (f->key == key)
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return &f->result;
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}
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return NULL;
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}
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static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp,
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struct tcf_result *res)
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{
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struct tcindex_data *p = tp->root;
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struct tcindex_filter_result *f;
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int key = (skb->tc_index & p->mask) >> p->shift;
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pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
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skb, tp, res, p);
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f = tcindex_lookup(p, key);
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if (!f) {
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if (!p->fall_through)
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return -1;
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res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key);
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res->class = 0;
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pr_debug("alg 0x%x\n", res->classid);
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return 0;
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}
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*res = f->res;
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pr_debug("map 0x%x\n", res->classid);
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return tcf_exts_exec(skb, &f->exts, res);
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}
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static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
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{
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struct tcindex_data *p = tp->root;
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struct tcindex_filter_result *r;
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pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
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if (p->perfect && handle >= p->alloc_hash)
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return 0;
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r = tcindex_lookup(p, handle);
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return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL;
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}
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static void tcindex_put(struct tcf_proto *tp, unsigned long f)
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{
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pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f);
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}
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static int tcindex_init(struct tcf_proto *tp)
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{
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struct tcindex_data *p;
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pr_debug("tcindex_init(tp %p)\n", tp);
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p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
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if (!p)
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return -ENOMEM;
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p->mask = 0xffff;
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p->hash = DEFAULT_HASH_SIZE;
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p->fall_through = 1;
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tp->root = p;
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return 0;
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}
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static int
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__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
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{
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struct tcindex_data *p = tp->root;
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struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg;
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struct tcindex_filter *f = NULL;
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pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f);
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if (p->perfect) {
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if (!r->res.class)
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return -ENOENT;
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} else {
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int i;
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struct tcindex_filter **walk = NULL;
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for (i = 0; i < p->hash; i++)
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for (walk = p->h+i; *walk; walk = &(*walk)->next)
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if (&(*walk)->result == r)
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goto found;
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return -ENOENT;
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found:
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f = *walk;
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if (lock)
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tcf_tree_lock(tp);
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*walk = f->next;
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if (lock)
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tcf_tree_unlock(tp);
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}
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tcf_unbind_filter(tp, &r->res);
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tcf_exts_destroy(tp, &r->exts);
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kfree(f);
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return 0;
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}
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static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
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{
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return __tcindex_delete(tp, arg, 1);
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}
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static inline int
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valid_perfect_hash(struct tcindex_data *p)
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{
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return p->hash > (p->mask >> p->shift);
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}
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static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
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[TCA_TCINDEX_HASH] = { .type = NLA_U32 },
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[TCA_TCINDEX_MASK] = { .type = NLA_U16 },
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[TCA_TCINDEX_SHIFT] = { .type = NLA_U32 },
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[TCA_TCINDEX_FALL_THROUGH] = { .type = NLA_U32 },
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[TCA_TCINDEX_CLASSID] = { .type = NLA_U32 },
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};
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static void tcindex_filter_result_init(struct tcindex_filter_result *r)
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{
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memset(r, 0, sizeof(*r));
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tcf_exts_init(&r->exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
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}
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static int
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tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
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u32 handle, struct tcindex_data *p,
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struct tcindex_filter_result *r, struct nlattr **tb,
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struct nlattr *est)
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{
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int err, balloc = 0;
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struct tcindex_filter_result new_filter_result, *old_r = r;
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struct tcindex_filter_result cr;
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struct tcindex_data cp;
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struct tcindex_filter *f = NULL; /* make gcc behave */
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struct tcf_exts e;
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tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
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err = tcf_exts_validate(net, tp, tb, est, &e);
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if (err < 0)
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return err;
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memcpy(&cp, p, sizeof(cp));
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tcindex_filter_result_init(&new_filter_result);
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tcindex_filter_result_init(&cr);
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if (old_r)
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cr.res = r->res;
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if (tb[TCA_TCINDEX_HASH])
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cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
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if (tb[TCA_TCINDEX_MASK])
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cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
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if (tb[TCA_TCINDEX_SHIFT])
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cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
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err = -EBUSY;
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/* Hash already allocated, make sure that we still meet the
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* requirements for the allocated hash.
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*/
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if (cp.perfect) {
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if (!valid_perfect_hash(&cp) ||
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cp.hash > cp.alloc_hash)
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goto errout;
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} else if (cp.h && cp.hash != cp.alloc_hash)
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goto errout;
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err = -EINVAL;
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if (tb[TCA_TCINDEX_FALL_THROUGH])
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cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
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if (!cp.hash) {
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/* Hash not specified, use perfect hash if the upper limit
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* of the hashing index is below the threshold.
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*/
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if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
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cp.hash = (cp.mask >> cp.shift) + 1;
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else
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cp.hash = DEFAULT_HASH_SIZE;
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}
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if (!cp.perfect && !cp.h)
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cp.alloc_hash = cp.hash;
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/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
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* but then, we'd fail handles that may become valid after some future
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* mask change. While this is extremely unlikely to ever matter,
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* the check below is safer (and also more backwards-compatible).
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*/
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if (cp.perfect || valid_perfect_hash(&cp))
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if (handle >= cp.alloc_hash)
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goto errout;
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err = -ENOMEM;
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if (!cp.perfect && !cp.h) {
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if (valid_perfect_hash(&cp)) {
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int i;
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cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
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if (!cp.perfect)
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goto errout;
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for (i = 0; i < cp.hash; i++)
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tcf_exts_init(&cp.perfect[i].exts, TCA_TCINDEX_ACT,
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TCA_TCINDEX_POLICE);
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balloc = 1;
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} else {
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cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
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if (!cp.h)
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goto errout;
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balloc = 2;
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}
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}
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if (cp.perfect)
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r = cp.perfect + handle;
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else
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r = tcindex_lookup(&cp, handle) ? : &new_filter_result;
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if (r == &new_filter_result) {
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f = kzalloc(sizeof(*f), GFP_KERNEL);
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if (!f)
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goto errout_alloc;
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}
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if (tb[TCA_TCINDEX_CLASSID]) {
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cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
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tcf_bind_filter(tp, &cr.res, base);
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}
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if (old_r)
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tcf_exts_change(tp, &r->exts, &e);
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else
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tcf_exts_change(tp, &cr.exts, &e);
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tcf_tree_lock(tp);
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if (old_r && old_r != r)
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tcindex_filter_result_init(old_r);
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memcpy(p, &cp, sizeof(cp));
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r->res = cr.res;
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if (r == &new_filter_result) {
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struct tcindex_filter **fp;
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f->key = handle;
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f->result = new_filter_result;
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f->next = NULL;
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for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next)
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/* nothing */;
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*fp = f;
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}
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tcf_tree_unlock(tp);
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return 0;
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errout_alloc:
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if (balloc == 1)
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kfree(cp.perfect);
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else if (balloc == 2)
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kfree(cp.h);
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errout:
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tcf_exts_destroy(tp, &e);
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return err;
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}
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static int
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tcindex_change(struct net *net, struct sk_buff *in_skb,
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struct tcf_proto *tp, unsigned long base, u32 handle,
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struct nlattr **tca, unsigned long *arg)
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{
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struct nlattr *opt = tca[TCA_OPTIONS];
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struct nlattr *tb[TCA_TCINDEX_MAX + 1];
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struct tcindex_data *p = tp->root;
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struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg;
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int err;
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pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
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"p %p,r %p,*arg 0x%lx\n",
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tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L);
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if (!opt)
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return 0;
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err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy);
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if (err < 0)
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return err;
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return tcindex_set_parms(net, tp, base, handle, p, r, tb,
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tca[TCA_RATE]);
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}
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static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
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{
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struct tcindex_data *p = tp->root;
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struct tcindex_filter *f, *next;
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int i;
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pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
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if (p->perfect) {
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for (i = 0; i < p->hash; i++) {
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if (!p->perfect[i].res.class)
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continue;
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if (walker->count >= walker->skip) {
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if (walker->fn(tp,
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(unsigned long) (p->perfect+i), walker)
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< 0) {
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walker->stop = 1;
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return;
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}
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}
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walker->count++;
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}
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}
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if (!p->h)
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return;
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for (i = 0; i < p->hash; i++) {
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for (f = p->h[i]; f; f = next) {
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next = f->next;
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if (walker->count >= walker->skip) {
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if (walker->fn(tp, (unsigned long) &f->result,
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walker) < 0) {
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walker->stop = 1;
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return;
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}
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}
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walker->count++;
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}
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}
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}
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static int tcindex_destroy_element(struct tcf_proto *tp,
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unsigned long arg, struct tcf_walker *walker)
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{
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return __tcindex_delete(tp, arg, 0);
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}
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static void tcindex_destroy(struct tcf_proto *tp)
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{
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struct tcindex_data *p = tp->root;
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struct tcf_walker walker;
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pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
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walker.count = 0;
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walker.skip = 0;
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walker.fn = &tcindex_destroy_element;
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tcindex_walk(tp, &walker);
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kfree(p->perfect);
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kfree(p->h);
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kfree(p);
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tp->root = NULL;
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}
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static int tcindex_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
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struct sk_buff *skb, struct tcmsg *t)
|
|
{
|
|
struct tcindex_data *p = tp->root;
|
|
struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
|
|
unsigned char *b = skb_tail_pointer(skb);
|
|
struct nlattr *nest;
|
|
|
|
pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
|
|
tp, fh, skb, t, p, r, b);
|
|
pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);
|
|
|
|
nest = nla_nest_start(skb, TCA_OPTIONS);
|
|
if (nest == NULL)
|
|
goto nla_put_failure;
|
|
|
|
if (!fh) {
|
|
t->tcm_handle = ~0; /* whatever ... */
|
|
if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) ||
|
|
nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) ||
|
|
nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) ||
|
|
nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through))
|
|
goto nla_put_failure;
|
|
nla_nest_end(skb, nest);
|
|
} else {
|
|
if (p->perfect) {
|
|
t->tcm_handle = r-p->perfect;
|
|
} else {
|
|
struct tcindex_filter *f;
|
|
int i;
|
|
|
|
t->tcm_handle = 0;
|
|
for (i = 0; !t->tcm_handle && i < p->hash; i++) {
|
|
for (f = p->h[i]; !t->tcm_handle && f;
|
|
f = f->next) {
|
|
if (&f->result == r)
|
|
t->tcm_handle = f->key;
|
|
}
|
|
}
|
|
}
|
|
pr_debug("handle = %d\n", t->tcm_handle);
|
|
if (r->res.class &&
|
|
nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid))
|
|
goto nla_put_failure;
|
|
|
|
if (tcf_exts_dump(skb, &r->exts) < 0)
|
|
goto nla_put_failure;
|
|
nla_nest_end(skb, nest);
|
|
|
|
if (tcf_exts_dump_stats(skb, &r->exts) < 0)
|
|
goto nla_put_failure;
|
|
}
|
|
|
|
return skb->len;
|
|
|
|
nla_put_failure:
|
|
nlmsg_trim(skb, b);
|
|
return -1;
|
|
}
|
|
|
|
static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
|
|
.kind = "tcindex",
|
|
.classify = tcindex_classify,
|
|
.init = tcindex_init,
|
|
.destroy = tcindex_destroy,
|
|
.get = tcindex_get,
|
|
.put = tcindex_put,
|
|
.change = tcindex_change,
|
|
.delete = tcindex_delete,
|
|
.walk = tcindex_walk,
|
|
.dump = tcindex_dump,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static int __init init_tcindex(void)
|
|
{
|
|
return register_tcf_proto_ops(&cls_tcindex_ops);
|
|
}
|
|
|
|
static void __exit exit_tcindex(void)
|
|
{
|
|
unregister_tcf_proto_ops(&cls_tcindex_ops);
|
|
}
|
|
|
|
module_init(init_tcindex)
|
|
module_exit(exit_tcindex)
|
|
MODULE_LICENSE("GPL");
|