Hello,
The following program causes leak on 2 objects allocated in netlink_sendmsg:
https://gist.githubusercontent.com/dvyukov/e840d00cfefe66c5e064/raw/6e5343a936bd3edd1b0803941cf7c1427050d9a5/gistfile1.txt
unreferenced object 0xffff880014f54840 (size 224):
comm "a.out", pid 11468, jiffies 4301602943 (age 29.985s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 10 3b 9d 3d 00 88 ff ff .........;.=....
backtrace:
[< inline >] kmemleak_alloc_recursive include/linux/kmemleak.h:47
[< inline >] slab_post_alloc_hook mm/slub.c:1335
[< inline >] slab_alloc_node mm/slub.c:2594
[<ffffffff816cc44d>] kmem_cache_alloc_node+0x16d/0x2e0 mm/slub.c:2630
[<ffffffff84b782ba>] __alloc_skb+0xba/0x5f0 net/core/skbuff.c:216
[< inline >] alloc_skb include/linux/skbuff.h:814
[< inline >] netlink_alloc_large_skb net/netlink/af_netlink.c:1695
[<ffffffff84cfd4b4>] netlink_sendmsg+0xfd4/0x1760
net/netlink/af_netlink.c:2486
[< inline >] sock_sendmsg_nosec net/socket.c:610
[<ffffffff84b5cc5a>] sock_sendmsg+0xca/0x110 net/socket.c:620
[<ffffffff84b5e689>] ___sys_sendmsg+0x309/0x840 net/socket.c:1946
[<ffffffff84b60c94>] __sys_sendmmsg+0x134/0x330 net/socket.c:2031
[< inline >] SYSC_sendmmsg net/socket.c:2059
[<ffffffff84b60ec5>] SyS_sendmmsg+0x35/0x60 net/socket.c:2054
[<ffffffff85c8eaf6>] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185
unreferenced object 0xffff880014facf60 (size 512):
comm "a.out", pid 11468, jiffies 4301602943 (age 29.985s)
hex dump (first 32 bytes):
48 ea fa 14 00 88 ff ff 00 00 00 00 ad 4e ad de H............N..
ff ff ff ff 00 00 00 00 ff ff ff ff ff ff ff ff ................
backtrace:
[< inline >] kmemleak_alloc_recursive include/linux/kmemleak.h:47
[< inline >] slab_post_alloc_hook mm/slub.c:1335
[< inline >] slab_alloc_node mm/slub.c:2594
[<ffffffff816d0b77>] __kmalloc_node_track_caller+0x217/0x3e0 mm/slub.c:4096
[<ffffffff84b75f71>] __kmalloc_reserve.isra.31+0x41/0xe0
net/core/skbuff.c:135
[<ffffffff84b782f0>] __alloc_skb+0xf0/0x5f0 net/core/skbuff.c:228
[< inline >] alloc_skb include/linux/skbuff.h:814
[< inline >] netlink_alloc_large_skb net/netlink/af_netlink.c:1695
[<ffffffff84cfd4b4>] netlink_sendmsg+0xfd4/0x1760
net/netlink/af_netlink.c:2486
[< inline >] sock_sendmsg_nosec net/socket.c:610
[<ffffffff84b5cc5a>] sock_sendmsg+0xca/0x110 net/socket.c:620
[<ffffffff84b5e689>] ___sys_sendmsg+0x309/0x840 net/socket.c:1946
[<ffffffff84b60c94>] __sys_sendmmsg+0x134/0x330 net/socket.c:2031
[< inline >] SYSC_sendmmsg net/socket.c:2059
[<ffffffff84b60ec5>] SyS_sendmmsg+0x35/0x60 net/socket.c:2054
[<ffffffff85c8eaf6>] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185
On commit 8513342170278468bac126640a5d2d12ffbff106 (Dec 28).