From: Ido Schimmel Date: Wed, 15 Mar 2023 12:40:09 +0000 (+0200) Subject: ipv4: Fix incorrect table ID in IOCTL path X-Git-Tag: v6.6.7~3270^2~16 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8a2618e14f81604a9b6ad305d57e0c8da939cd65;p=platform%2Fkernel%2Flinux-starfive.git ipv4: Fix incorrect table ID in IOCTL path Commit f96a3d74554d ("ipv4: Fix incorrect route flushing when source address is deleted") started to take the table ID field in the FIB info structure into account when determining if two structures are identical or not. This field is initialized using the 'fc_table' field in the route configuration structure, which is not set when adding a route via IOCTL. The above can result in user space being able to install two identical routes that only differ in the table ID field of their associated FIB info. Fix by initializing the table ID field in the route configuration structure in the IOCTL path. Before the fix: # ip route add default via 192.0.2.2 # route add default gw 192.0.2.2 # ip -4 r show default # default via 192.0.2.2 dev dummy10 # default via 192.0.2.2 dev dummy10 After the fix: # ip route add default via 192.0.2.2 # route add default gw 192.0.2.2 SIOCADDRT: File exists # ip -4 r show default default via 192.0.2.2 dev dummy10 Audited the code paths to ensure there are no other paths that do not properly initialize the route configuration structure when installing a route. Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs") Fixes: f96a3d74554d ("ipv4: Fix incorrect route flushing when source address is deleted") Reported-by: gaoxingwang Link: https://lore.kernel.org/netdev/20230314144159.2354729-1-gaoxingwang1@huawei.com/ Tested-by: gaoxingwang Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20230315124009.4015212-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski --- diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index b5736ef..390f4be 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -576,6 +576,9 @@ static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt, cfg->fc_scope = RT_SCOPE_UNIVERSE; } + if (!cfg->fc_table) + cfg->fc_table = RT_TABLE_MAIN; + if (cmd == SIOCDELRT) return 0;