On 8 June 2015 at 18:45, Viacheslav Dubeyko <slava@xxxxxxxxxxx> wrote: > On Mon, 2015-06-08 at 18:32 +0200, Sergei Antonov wrote: >> On 8 June 2015 at 17:45, Vyacheslav Dubeyko <slava@xxxxxxxxxxx> wrote: >> > On Sun, 2015-06-07 at 02:42 +0200, Sergei Antonov wrote: >> >> Fix this bugreport by Sasha Levin: >> >> http://lkml.org/lkml/2015/2/20/85 ("use after free") >> >> Make sure mapped pages are available for the entire lifetime of hfs_bnode. >> >> >> > >> > Sorry, I missed the point. What do you try to fix? How this change fixes >> > the issue? >> > >> > I think that maybe this fix makes sense. But it needs to describe it >> > more deeply. Could you describe the fix with more details? >> >> You are basically saying you don’t understand it. Too bad, because the >> bug is very simple. It is the „use after free“ type of bug, and it can >> be illustrated by this: >> (1) void *ptr = malloc(…); >> (2) free(ptr); >> (3) memcpy(…, ptr, 1); >> Guess which two of these three lines are executed in wrong order. >> >> My patch is about the same type of bug, but with memory pages mapping. >> The driver currently accesses pages that may be unavailable, or >> contain different data. The problem is more likely to occur when >> memory is a limited resource. I reproduced it while running a >> memory-hungry program. > > I worried not about myself but about potential readers of description of > the fix. The description is completely obscure. And it needs to describe > the fix in clear and descriptive manner. This is my request. Please, > describe the fix in a clear way. The description is just right. Anton, can you give your opinion? You commented my patches before. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
