Hi, Thank you so much for your time and reply.
We understand that the entire point of `xrealloc` is never returning 0 to client users/developers who use this function. However, the issue we reported here happens when the `xrealloc` internally handles the returned 0 from `realloc` or `malloc` functions. In general, the key point is that the function `OUT_OF_MEM()` (invoked when the `result` gets a 0 in the implementation of `xrealloc`) does not immediately terminate the program execution, and the function `OUT_OF_MEM()` will continue to allocate buffers via `xrealloc` for printing purposes in the following and then terminate. Specifically, the continuous execution of function `OUT_OF_MEM()` calls the `xrealloc` again through the `get_buffer` function (`OUT_OF_MEM()` is a macro definition that will call the function `fatal`, which finally invocates the function `get_buffer`). As we mentioned in the initial report, once the second invocation of `xrealloc` (i.e., the one called inside `OUT_OF_MEM()`) returns zero and calls `OUT_OF_MEM()` again, a null pointer dereference is occurred in `fmtbuf.buffer[need-1] = '\0';` in the function `get_buffer`. Please kindly check my explanation above and correct me if I am wrong. Thank you so much again and looking forward to hearing from you back again. Best regards, Haoxin Paul D. Smith <invalid.nore...@gnu.org> 于2024年1月7日周日 01:49写道： > Update of bug#64551 (group make): > > Status: None => Duplicate > > Assigned to: None => psmith > > Open/Closed: Open => Closed > > > _______________________________________________________ > > Follow-up Comment #1: > > I don't see how the "second" xrealloc() would return 0; the entire point of > xrealloc is that it never returns 0. > > However, I can see where the behavior of the code might lead to an infinite > loop. > > This issue was already addressed in GNU Make 4.3 via bug #13651 > The version you're testing (4.2) was released in 2016. > > It's certainly helpful to check for errors in tools like GNU Make but > please > check either the most recent published version or, even better, the current > Git HEAD version. > > Thanks! > > > _______________________________________________________ > > Reply to this item at: > > <https://savannah.gnu.org/bugs/?64551> > > _______________________________________________ > Message sent via Savannah > https://savannah.gnu.org/ > >
