diff mbox series

[net-next,4/4] bpf, sockmap: Fix double uncharge the mem of sk_msg

Message ID 20220221103105.4028557-5-wangyufen@huawei.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series bpf, sockmap: Fix memleaks and issues of mem charge/uncharge | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers success CCed 17 of 17 maintainers
netdev/build_clang success Errors and warnings before: 18 this patch: 18
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 7 this patch: 7
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next success VM_Test

Commit Message

wangyufen Feb. 21, 2022, 10:31 a.m. UTC
If tcp_bpf_sendmsg is running during a tear down operation, psock may be
freed.

tcp_bpf_sendmsg()
 tcp_bpf_send_verdict()
  sk_msg_return()
  tcp_bpf_sendmsg_redir()
   unlikely(!psock))
   sk_msg_free()

The mem of msg has been uncharged in tcp_bpf_send_verdict() by
sk_msg_return(), so we need to use sk_msg_free_nocharge while psock
is null.

This issue can cause the following info:
WARNING: CPU: 0 PID: 2136 at net/ipv4/af_inet.c:155 inet_sock_destruct+0x13c/0x260
Call Trace:
 <TASK>
 __sk_destruct+0x24/0x1f0
 sk_psock_destroy+0x19b/0x1c0
 process_one_work+0x1b3/0x3c0
 worker_thread+0x30/0x350
 ? process_one_work+0x3c0/0x3c0
 kthread+0xe6/0x110
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x22/0x30
 </TASK>

Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
---
 net/ipv4/tcp_bpf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c
index 1f0364e06619..03c037d2a055 100644
--- a/net/ipv4/tcp_bpf.c
+++ b/net/ipv4/tcp_bpf.c
@@ -139,7 +139,7 @@  int tcp_bpf_sendmsg_redir(struct sock *sk, struct sk_msg *msg,
 	int ret;
 
 	if (unlikely(!psock)) {
-		sk_msg_free(sk, msg);
+		sk_msg_free_nocharge(sk, msg);
 		return 0;
 	}
 	ret = ingress ? bpf_tcp_ingress(sk, psock, msg, bytes, flags) :