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| author |   Cong Wang <xiyou.wangcong@gmail.com> | 2019-06-28 11:03:41 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2019-07-01 19:15:46 -0700 |
| commit | e33d2b74d805af0e4c8060f41040595ba105a520 (patch) | |
| tree | 0952dd1b3f4617a5309a0070b192e247122b3aca /net/sched/act_api.c | |
| parent | Merge branch 'vsock-virtio-fixes' (diff) | |
| download | linux-dev-e33d2b74d805af0e4c8060f41040595ba105a520.tar.xz linux-dev-e33d2b74d805af0e4c8060f41040595ba105a520.zip | |
idr: fix overflow case for idr_for_each_entry_ul()
idr_for_each_entry_ul() is buggy as it can't handle overflow
case correctly. When we have an ID == UINT_MAX, it becomes an
infinite loop. This happens when running on 32-bit CPU where
unsigned long has the same size with unsigned int.
There is no better way to fix this than casting it to a larger
integer, but we can't just 64 bit integer on 32 bit CPU. Instead
we could just use an additional integer to help us to detect this
overflow case, that is, adding a new parameter to this macro.
Fortunately tc action is its only user right now.
Fixes: 65a206c01e8e ("net/sched: Change act_api and act_xxx modules to use IDR")
Reported-by: Li Shuang <shuali@redhat.com>
Tested-by: Davide Caratti <dcaratti@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Chris Mi <chrism@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
| -rw-r--r-- | net/sched/act_api.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/net/sched/act_api.c b/net/sched/act_api.c index 4e5d2e9ace5d..339712296164 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -221,12 +221,13 @@ static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, struct idr *idr = &idrinfo->action_idr; struct tc_action *p; unsigned long id = 1; + unsigned long tmp; mutex_lock(&idrinfo->lock); s_i = cb->args[0]; - idr_for_each_entry_ul(idr, p, id) { + idr_for_each_entry_ul(idr, p, tmp, id) { index++; if (index < s_i) continue; @@ -292,6 +293,7 @@ static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, struct idr *idr = &idrinfo->action_idr; struct tc_action *p; unsigned long id = 1; + unsigned long tmp; nest = nla_nest_start_noflag(skb, 0); if (nest == NULL) @@ -300,7 +302,7 @@ static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, goto nla_put_failure; mutex_lock(&idrinfo->lock); - idr_for_each_entry_ul(idr, p, id) { + idr_for_each_entry_ul(idr, p, tmp, id) { ret = tcf_idr_release_unsafe(p); if (ret == ACT_P_DELETED) { module_put(ops->owner); @@ -533,8 +535,9 @@ void tcf_idrinfo_destroy(const struct tc_action_ops *ops, struct tc_action *p; int ret; unsigned long id = 1; + unsigned long tmp; - idr_for_each_entry_ul(idr, p, id) { + idr_for_each_entry_ul(idr, p, tmp, id) { ret = __tcf_idr_release(p, false, true); if (ret == ACT_P_DELETED) module_put(ops->owner); |