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| author | Horatiu Vultur <horatiu.vultur@microchip.com> | 2020-05-25 09:55:41 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-05-25 18:09:26 -0700 |
| commit | 617504c67e01d30310558442777a4112ea6d587d (patch) | |
| tree | f1b8a0e03ddac483345cec7e9588abbfe26c79e4 /net/bridge | |
| parent | 07153961f82878dee73717f64761d67dff9546c1 (diff) | |
| download | linux-617504c67e01d30310558442777a4112ea6d587d.tar.gz linux-617504c67e01d30310558442777a4112ea6d587d.tar.bz2 linux-617504c67e01d30310558442777a4112ea6d587d.zip | |
bridge: mrp: Fix out-of-bounds read in br_mrp_parse
The issue was reported by syzbot. When the function br_mrp_parse was
called with a valid net_bridge_port, the net_bridge was an invalid
pointer. Therefore the check br->stp_enabled could pass/fail
depending where it was pointing in memory.
The fix consists of setting the net_bridge pointer if the port is a
valid pointer.
Reported-by: syzbot+9c6f0f1f8e32223df9a4@syzkaller.appspotmail.com
Fixes: 6536993371fa ("bridge: mrp: Integrate MRP into the bridge")
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/bridge')
| -rw-r--r-- | net/bridge/br_mrp_netlink.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/net/bridge/br_mrp_netlink.c b/net/bridge/br_mrp_netlink.c index 397e7f710772..4a08a99519b0 100644 --- a/net/bridge/br_mrp_netlink.c +++ b/net/bridge/br_mrp_netlink.c @@ -27,6 +27,12 @@ int br_mrp_parse(struct net_bridge *br, struct net_bridge_port *p, struct nlattr *tb[IFLA_BRIDGE_MRP_MAX + 1]; int err; + /* When this function is called for a port then the br pointer is + * invalid, therefor set the br to point correctly + */ + if (p) + br = p->br; + if (br->stp_enabled != BR_NO_STP) { NL_SET_ERR_MSG_MOD(extack, "MRP can't be enabled if STP is already enabled"); return -EINVAL; |