Unable to find actual suspect through code search and also from the provided CL, hence adding appropriate label and marking it as untriaged.

metzman@: Could you please confirm is this issue is similar to bug 796680 or not ?

Thanks!

I think bug 796680 is unrelated. This bug was found by libFuzzer whereas bug 796680 only concerns AFL.

Could some one from network team can look in to this issue?

Thanks!

I'll try to repro this later today.

This looks like a distinct timeout from  Issue 802258  (interestingly all of these got filed around the same time, so I am guessing something changed on the fuzzing side in expanding inputs?)

At first glance the profile blames FtpCtrlResponseBuffer::ExtractFullLinesFromBuffer(), which is what splits the input into parsed lines:

Samples: 272K of event 'cycles', Event count (approx.): 253360746689                                                              
  Children      Self  Command          Shared Object               Symbol                                                         
+   98.01%     0.00%  net_url_request  net_url_req[.] base::internal::FunctorTraits<void (net::FuzzedSocket::*)(base::RepeatingCal
+   97.80%     0.00%  net_url_request  net_url_req[.] net::FuzzedSocket::OnReadComplete                                           
+   97.80%     0.00%  net_url_request  net_url_req[.] base::RepeatingCallback<void (int)>::Run                                    
+   97.79%     0.00%  net_url_request  libnet.so  [.] base::internal::Invoker<base::internal::BindState<void (net::FtpNetworkTrans
+   97.79%     0.00%  net_url_request  libnet.so  [.] base::internal::Invoker<base::internal::BindState<void (net::FtpNetworkTrans
+   97.79%     0.00%  net_url_request  libnet.so  [.] base::internal::InvokeHelper<false, void>::MakeItSo<void (net::FtpNetworkTra
+   97.78%     0.00%  net_url_request  libnet.so  [.] base::internal::FunctorTraits<void (net::FtpNetworkTransaction::*)(int), voi
+   97.78%     0.00%  net_url_request  libnet.so  [.] net::FtpNetworkTransaction::OnIOComplete                                    
+   97.77%     0.01%  net_url_request  libnet.so  [.] net::FtpNetworkTransaction::DoLoop                                          
+   96.89%     0.00%  net_url_request  libnet.so  [.] net::FtpNetworkTransaction::DoCtrlReadComplete                              
+   96.87%     0.00%  net_url_request  libnet.so  [.] net::FtpCtrlResponseBuffer::ConsumeData                                     
+   90.77%    27.20%  net_url_request  libnet.so  [.] net::FtpCtrlResponseBuffer::ExtractFullLinesFromBuffer                      
+   58.57%    58.50%  net_url_request  net_url_req[.] __sanitizer_cov_trace_pc_guard                                              
+   33.07%     7.94%  net_url_request  libnet.so  [.] std::__1::__compressed_pair_elem<std::__1::basic_string<char, std::__1::char
+    9.92%     2.19%  net_url_request  libnet.so  [.] std::__1::__compressed_pair_elem<std::__1::basic_string<char, std::__1::char
+    2.72%     0.00%  net_url_request  libnet.so  [.] 0xffff800817aea370                                                          
+    2.72%     2.72%  net_url_request  libnet.so  [.] 0x0000000001724370                                                          
+    1.13%     0.01%  net_url_request  libbase.so [.] base::SequenceCheckerImpl::CalledOnValidSequence                            
+    0.86%     0.01%  net_url_request  libnet.so  [.] net::FtpNetworkTransaction::DoCtrlRead                                      
+    0.83%     0.01%  net_url_request  net_url_req[.] net::FuzzedSocket::Read                                                     
+    0.73%     0.00%  net_url_request  libbase.so [.] base::SequenceCheckerImpl::Core::CalledOnValidSequence                      
+    0.70%     0.01%  net_url_request  libbase.so [.] base::ThreadCheckerImpl::CalledOnValidThread                                
+    0.53%     0.00%  net_url_request  libbase.so [.] base::AutoLock::AutoLock                                                    
+    0.51%     0.00%  net_url_request  libbase.so [.] base::Lock::Acquire                                                         
     0.41%     0.00%  net_url_request  libbase.so [.] base::internal::WeakReference::is_valid                                     
     0.41%     0.00%  net_url_request  net_url_req[.] base::WeakPtr<net::FuzzedSocket>::get                                       
     0.39%     0.00%  net_url_request  libbase.so [.] base::internal::IncomingTaskQueue::TriageQueue::HasTasks                    
     0.39%     0.01%  net_url_request  libbase.so [.] base::internal::LockImpl::Lock                                              
     0.38%     0.00%  net_url_request  libbase.so [.] base::internal::WeakReference::Flag::IsValid                                
     0.34%     0.01%  net_url_request  libbase.so [.] base::internal::IncomingTaskQueue::TriageQueue::ReloadFromIncomingQueueIfEmp
     0.33%     0.00%  net_url_request  libbase.so [.] base::OnceCallback<void ()>::~OnceCallback                                  
     0.33%     0.00%  net_url_request  libbase.so [.] base::internal::CallbackBase::~CallbackBase                                 

We are closing all ooms and timeouts that are unreproducible. We won't be filing such bugs in future.