In the Linux kernel, the following vulnerability has been resolved:
net: rds: fix memory leak in rds_recvmsg
Syzbot reported memory leak in rds. The problem was in unputted refcount in case of error.
int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, int msg_flags) { ...
if (!rds_next_incoming(rs, &inc)) {
...
}
After this "if" inc refcount incremented and
if (rds_cmsg_recv(inc, msg, rs)) {
ret = -EFAULT;
goto out;
}
... out: return ret; }
in case of rds_cmsg_recv() fail the refcount won't be decremented. And it's easy to see from ftrace log, that rds_inc_addref() don't have rds_inc_put() pair in rds_recvmsg() after rds_cmsg_recv()
| rds_recvmsg() {
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47249.json"
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