linux/include/linux/igmp.h

143 lines
4.4 KiB

ip: fix ip_mc_may_pull() return value ip_mc_may_pull() must return 0 if there is a problem, not an errno. syzbot reported : BUG: KASAN: use-after-free in br_ip4_multicast_igmp3_report net/bridge/br_multicast.c:947 [inline] BUG: KASAN: use-after-free in br_multicast_ipv4_rcv net/bridge/br_multicast.c:1631 [inline] BUG: KASAN: use-after-free in br_multicast_rcv+0x3cd8/0x4440 net/bridge/br_multicast.c:1741 Read of size 4 at addr ffff88820a4084ee by task syz-executor.2/11183 CPU: 1 PID: 11183 Comm: syz-executor.2 Not tainted 5.0.0+ #14 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 br_ip4_multicast_igmp3_report net/bridge/br_multicast.c:947 [inline] br_multicast_ipv4_rcv net/bridge/br_multicast.c:1631 [inline] br_multicast_rcv+0x3cd8/0x4440 net/bridge/br_multicast.c:1741 br_handle_frame_finish+0xa3a/0x14c0 net/bridge/br_input.c:108 br_nf_hook_thresh+0x2ec/0x380 net/bridge/br_netfilter_hooks.c:1005 br_nf_pre_routing_finish+0x8e2/0x1750 net/bridge/br_netfilter_hooks.c:410 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] br_nf_pre_routing+0x7e7/0x13a0 net/bridge/br_netfilter_hooks.c:506 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline] nf_hook_slow+0xbf/0x1f0 net/netfilter/core.c:511 nf_hook include/linux/netfilter.h:244 [inline] NF_HOOK include/linux/netfilter.h:287 [inline] br_handle_frame+0x95b/0x1450 net/bridge/br_input.c:305 __netif_receive_skb_core+0xa96/0x3040 net/core/dev.c:4902 __netif_receive_skb_one_core+0xa8/0x1a0 net/core/dev.c:4971 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083 netif_receive_skb_internal+0x117/0x660 net/core/dev.c:5186 netif_receive_skb+0x6e/0x5a0 net/core/dev.c:5261 Fixes: ba5ea614622d ("bridge: simplify ip_mc_check_igmp() and ipv6_mc_check_mld() calls") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-09 14:43:38 -08:00
ipv4/igmp: init group mode as INCLUDE when join source group Based on RFC3376 5.1 If no interface state existed for that multicast address before the change (i.e., the change consisted of creating a new per-interface record), or if no state exists after the change (i.e., the change consisted of deleting a per-interface record), then the "non-existent" state is considered to have a filter mode of INCLUDE and an empty source list. Which means a new multicast group should start with state IN(). Function ip_mc_join_group() works correctly for IGMP ASM(Any-Source Multicast) mode. It adds a group with state EX() and inits crcount to mc_qrv, so the kernel will send a TO_EX() report message after adding group. But for IGMPv3 SSM(Source-specific multicast) JOIN_SOURCE_GROUP mode, we split the group joining into two steps. First we join the group like ASM, i.e. via ip_mc_join_group(). So the state changes from IN() to EX(). Then we add the source-specific address with INCLUDE mode. So the state changes from EX() to IN(A). Before the first step sends a group change record, we finished the second step. So we will only send the second change record. i.e. TO_IN(A). Regarding the RFC stands, we should actually send an ALLOW(A) message for SSM JOIN_SOURCE_GROUP as the state should mimic the 'IN() to IN(A)' transition. The issue was exposed by commit a052517a8ff65 ("net/multicast: should not send source list records when have filter mode change"). Before this change, we used to send both ALLOW(A) and TO_IN(A). After this change we only send TO_IN(A). Fix it by adding a new parameter to init group mode. Also add new wrapper functions so we don't need to change too much code. v1 -> v2: In my first version I only cleared the group change record. But this is not enough. Because when a new group join, it will init as EXCLUDE and trigger an filter mode change in ip/ip6_mc_add_src(), which will clear all source addresses' sf_crcount. This will prevent early joined address sending state change records if multi source addressed joined at the same time. In v2 patch, I fixed it by directly initializing the mode to INCLUDE for SSM JOIN_SOURCE_GROUP. I also split the original patch into two separated patches for IPv4 and IPv6. Fixes: a052517a8ff65 ("net/multicast: should not send source list records when have filter mode change") Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-10 22:41:26 +08:00
net: Fix ip_mc_{dec,inc}_group allocation context After 4effd28c1245 ("bridge: join all-snoopers multicast address"), I started seeing the following sleep in atomic warnings: [ 26.763893] BUG: sleeping function called from invalid context at mm/slab.h:421 [ 26.771425] in_atomic(): 1, irqs_disabled(): 0, pid: 1658, name: sh [ 26.777855] INFO: lockdep is turned off. [ 26.781916] CPU: 0 PID: 1658 Comm: sh Not tainted 5.0.0-rc4 #20 [ 26.787943] Hardware name: BCM97278SV (DT) [ 26.792118] Call trace: [ 26.794645] dump_backtrace+0x0/0x170 [ 26.798391] show_stack+0x24/0x30 [ 26.801787] dump_stack+0xa4/0xe4 [ 26.805182] ___might_sleep+0x208/0x218 [ 26.809102] __might_sleep+0x78/0x88 [ 26.812762] kmem_cache_alloc_trace+0x64/0x28c [ 26.817301] igmp_group_dropped+0x150/0x230 [ 26.821573] ip_mc_dec_group+0x1b0/0x1f8 [ 26.825585] br_ip4_multicast_leave_snoopers.isra.11+0x174/0x190 [ 26.831704] br_multicast_toggle+0x78/0xcc [ 26.835887] store_bridge_parm+0xc4/0xfc [ 26.839894] multicast_snooping_store+0x3c/0x4c [ 26.844517] dev_attr_store+0x44/0x5c [ 26.848262] sysfs_kf_write+0x50/0x68 [ 26.852006] kernfs_fop_write+0x14c/0x1b4 [ 26.856102] __vfs_write+0x60/0x190 [ 26.859668] vfs_write+0xc8/0x168 [ 26.863059] ksys_write+0x70/0xc8 [ 26.866449] __arm64_sys_write+0x24/0x30 [ 26.870458] el0_svc_common+0xa0/0x11c [ 26.874291] el0_svc_handler+0x38/0x70 [ 26.878120] el0_svc+0x8/0xc while toggling the bridge's multicast_snooping attribute dynamically. Pass a gfp_t down to igmpv3_add_delrec(), introduce __igmp_group_dropped() and introduce __ip_mc_dec_group() to take a gfp_t argument. Similarly introduce ____ip_mc_inc_group() and __ip_mc_inc_group() to allow caller to specify gfp_t. IPv6 part of the patch appears fine. Fixes: 4effd28c1245 ("bridge: join all-snoopers multicast address") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-01 20:20:52 -08:00