diff options
| author | Kuniyuki Iwashima <kuniyu@google.com> | 2026-03-01 01:17:33 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-03-03 05:49:41 +0300 |
| commit | bddafc06ca5ee1be4d10061f7954c6d6be5dc1d8 (patch) | |
| tree | 277923ee9b620b511a000d8b5ad27f5296edc5b0 /net | |
| parent | 3c1e53e55418d4ca4040e281501643a96e227974 (diff) | |
| download | linux-bddafc06ca5ee1be4d10061f7954c6d6be5dc1d8.tar.xz | |
ipmr: Don't hold RTNL for ipmr_rtm_route().
ipmr_mfc_add() and ipmr_mfc_delete() are already protected
by a dedicated mutex.
rtm_to_ipmr_mfcc() calls __ipmr_get_table(), __dev_get_by_index(),
amd ipmr_find_vif().
Once __dev_get_by_index() is converted to dev_get_by_index_rcu(),
we can move the other two functions under that same RCU section
and drop RTNL for ipmr_rtm_route().
Let's do that conversion and drop ASSERT_RTNL() in
mr_call_mfc_notifiers().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260228221800.1082070-16-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/ipmr.c | 34 |
1 files changed, 21 insertions, 13 deletions
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index d4983d8a9b2a..8a08d09b4c30 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -1211,7 +1211,6 @@ static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent) struct net *net = read_pnet(&mrt->net); struct mfc_cache *c; - /* The entries are added/deleted only under RTNL */ rcu_read_lock(); c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr, mfc->mfcc_mcastgrp.s_addr, parent); @@ -1238,7 +1237,6 @@ static int ipmr_mfc_add(struct net *net, struct mr_table *mrt, if (mfc->mfcc_parent >= MAXVIFS) return -ENFILE; - /* The entries are added/deleted only under RTNL */ rcu_read_lock(); c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr, mfc->mfcc_mcastgrp.s_addr, parent); @@ -2853,10 +2851,10 @@ static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh, { struct net_device *dev = NULL; u32 tblid = RT_TABLE_DEFAULT; + int ret, rem, iif = 0; struct mr_table *mrt; struct nlattr *attr; struct rtmsg *rtm; - int ret, rem; ret = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX, rtm_ipmr_policy, extack); @@ -2883,11 +2881,7 @@ static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh, mfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr); break; case RTA_IIF: - dev = __dev_get_by_index(net, nla_get_u32(attr)); - if (!dev) { - ret = -ENODEV; - goto out; - } + iif = nla_get_u32(attr); break; case RTA_MULTIPATH: if (ipmr_nla_get_ttls(attr, mfcc) < 0) { @@ -2903,16 +2897,30 @@ static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh, break; } } + + rcu_read_lock(); + mrt = __ipmr_get_table(net, tblid); if (!mrt) { ret = -ENOENT; - goto out; + goto unlock; } + + if (iif) { + dev = dev_get_by_index_rcu(net, iif); + if (!dev) { + ret = -ENODEV; + goto unlock; + } + + mfcc->mfcc_parent = ipmr_find_vif(mrt, dev); + } + *mrtret = mrt; *mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0; - if (dev) - mfcc->mfcc_parent = ipmr_find_vif(mrt, dev); +unlock: + rcu_read_unlock(); out: return ret; } @@ -3343,9 +3351,9 @@ static const struct rtnl_msg_handler ipmr_rtnl_msg_handlers[] __initconst = { {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_GETLINK, .dumpit = ipmr_rtm_dumplink, .flags = RTNL_FLAG_DUMP_UNLOCKED}, {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_NEWROUTE, - .doit = ipmr_rtm_route}, + .doit = ipmr_rtm_route, .flags = RTNL_FLAG_DOIT_UNLOCKED}, {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_DELROUTE, - .doit = ipmr_rtm_route}, + .doit = ipmr_rtm_route, .flags = RTNL_FLAG_DOIT_UNLOCKED}, {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_GETROUTE, .doit = ipmr_rtm_getroute, .dumpit = ipmr_rtm_dumproute, .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED}, |