On Tue, 22 Oct 2024 14:51:39 +0800 fengchengwen <fengcheng...@huawei.com> wrote:
> On 2024/10/22 9:08, Stephen Hemminger wrote: > > On Mon, 21 Oct 2024 21:30:02 +0300 > > Isaac Boukris <ibouk...@gmail.com> wrote: > > > >> Hello, > >> > >> I was debugging a crash resulting from strtok() returning NULL > >> unexpectedly (string still had tokens and delimiters), and the only > >> explanation I could come up with was that strtok is thread-unsafe and > >> another thread could have been calling it at the same time, and so I > >> changed it to use strtok_r(). > >> > >> That said, the only other possible use of strtok() that I could find > >> was in the dpdk code (telemetry), which brings me to my question, > >> should we consider changing all occurrences to strtok_r() or am I > >> missing something? there seem to be quite some in non-initialization > >> code. > >> > >> Thanks! > > > > > > Most of the uses are in tests and other single threaded code. > > In general, simpler just to use strtok_r everywhere and not worry about it. > > Similar to not using sprintf() and instead using snprintf(). > > I'm afraid I can't agree. > > DPDK is just a SDK, it's not an application (although DPDK provided simple > examples). > Many code will developped based on DPDK, we can't predict how it was > implemented. > So there maybe a DPDK thread and a application thread both invoke strtok(). > > From this point of view, I hope that DPDK solves some of the reentrant > problems of > such C functions (e.g. strtok()\strerror()). > > Actually, we've try to solve before, but unfortunately it wasn't merged. > 1\ strtok(): > https://inbox.dpdk.org/dev/20231114110006.91148-1-haij...@huawei.com/T/#u > 2\ strerror(): > https://inbox.dpdk.org/dev/20231114123552.398072-1-huangdeng...@huawei.com/T/#u > > > > > Some code scanners like codeql also flag this. > The usages of strtok() and strerror() in init code are fine. Stuff only called from eal_init() like devargs should be safe, but fixing it makes sense. Perhaps a coccinelle script could help here.
