rtnetlink: restore handling of dumpit return value in rtnl_dump_all()
For non-zero return from dumpit() we should break the loop
in rtnl_dump_all() and return the result. Otherwise, e.g.,
we could get the memory leak in inet6_dump_fib() [1]. The
pointer to the allocated struct fib6_walker there (saved
in cb->args) can be lost, reset on the next iteration.
Fix it by partially restoring the previous behavior before
commit c63586dc9b3e ("net: rtnl_dump_all needs to propagate
error from dumpit function"). The returned error from
dumpit() is still passed further.
[1]:
unreferenced object 0xffff88001322a200 (size 96):
comm "sshd", pid 1484, jiffies 4296032768 (age 1432.542s)
hex dump (first 32 bytes):
00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de ................
18 09 41 36 00 88 ff ff 18 09 41 36 00 88 ff ff ..A6......A6....
backtrace:
[<0000000095846b39>] kmem_cache_alloc_trace+0x151/0x220
[<000000007d12709f>] inet6_dump_fib+0x68d/0x940
[<000000002775a316>] rtnl_dump_all+0x1d9/0x2d0
[<00000000d7cd302b>] netlink_dump+0x945/0x11a0
[<000000002f43485f>] __netlink_dump_start+0x55d/0x800
[<00000000f76bbeec>] rtnetlink_rcv_msg+0x4fa/0xa00
[<000000009b5761f3>] netlink_rcv_skb+0x29c/0x420
[<0000000087a1dae1>] rtnetlink_rcv+0x15/0x20
[<00000000691b703b>] netlink_unicast+0x4e3/0x6c0
[<00000000b5be0204>] netlink_sendmsg+0x7f2/0xba0
[<0000000096d2aa60>] sock_sendmsg+0xba/0xf0
[<000000008c1b786f>] __sys_sendto+0x1e4/0x330
[<0000000019587b3f>] __x64_sys_sendto+0xe1/0x1a0
[<00000000071f4d56>] do_syscall_64+0x9f/0x300
[<000000002737577f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[<0000000057587684>] 0xffffffffffffffff
Fixes: c63586dc9b3e ("net: rtnl_dump_all needs to propagate error from dumpit function")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed