On Mon, Dec 6, 2021 at 10:22 PM <andrey.konovalov@xxxxxxxxx> wrote: > > From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > > Hi, > > This patchset adds vmalloc tagging support for SW_TAGS and HW_TAGS > KASAN modes. > > The tree with patches is available here: > > https://github.com/xairy/linux/tree/up-kasan-vmalloc-tags-v2 > > About half of patches are cleanups I went for along the way. None of > them seem to be important enough to go through stable, so I decided > not to split them out into separate patches/series. > > I'll keep the patchset based on the mainline for now. Once the > high-level issues are resolved, I'll rebase onto mm - there might be > a few conflicts right now. > > The patchset is partially based on an early version of the HW_TAGS > patchset by Vincenzo that had vmalloc support. Thus, I added a > Co-developed-by tag into a few patches. > > SW_TAGS vmalloc tagging support is straightforward. It reuses all of > the generic KASAN machinery, but uses shadow memory to store tags > instead of magic values. Naturally, vmalloc tagging requires adding > a few kasan_reset_tag() annotations to the vmalloc code. > > HW_TAGS vmalloc tagging support stands out. HW_TAGS KASAN is based on > Arm MTE, which can only assigns tags to physical memory. As a result, > HW_TAGS KASAN only tags vmalloc() allocations, which are backed by > page_alloc memory. It ignores vmap() and others. > > Changes in v1->v2: > - Move memory init for vmalloc() into vmalloc code for HW_TAGS KASAN. > - Minor fixes and code reshuffling, see patches for lists of changes. > > Thanks! FTR, I found a few issues with a tag propagating to PC (in BPF JIT and a few other places). Will address them in v3.
