On 4/27/20 8:38 AM, Matthew Wilcox wrote:
On Sun, Apr 26, 2020 at 10:02:12PM -0400, Waiman Long wrote:In a couple of places in the slub memory allocator, the code uses "s->offset" as a check to see if the free pointer is put right after the object. That check is no longer true with commit 3202fa62fb43 ("slub: relocate freelist pointer to middle of object"). As a result, echoing "1" into the validate sysfs file, e.g. of dentry, may cause a bunch of "Freepointer corrupt" error reports to appear with the system in panic afterwards. To fix it, use the check "s->offset == s->inuse" instead.I think a little refactoring would make this more clear. unsigned int track_offset(const struct kmem_cache *s) { return s->inuse + (s->offset == s->inuse) ? sizeof(void *) : 0; }
Yes, that was what I am thinking of doing in v2. Thanks, Longman
