Messages in this thread | | | Date | Sat, 7 Oct 2023 13:37:59 +0200 | From | Greg KH <> | Subject | Re: [PATCH] binder: add mutex_lock for mmap and NULL when free |
| |
On Sat, Oct 07, 2023 at 07:34:05PM +0800, Kassey Li wrote: > > > On 2023/10/7 19:18, Greg KH wrote: > > On Sat, Oct 07, 2023 at 07:07:40PM +0800, Kassey Li wrote: > > > > > > > > > On 2023/10/7 14:44, Greg KH wrote: > > > > On Sat, Oct 07, 2023 at 11:40:46AM +0800, Kassey Li wrote: > > > > > Enforce alloc->mutex in binder_alloc_mmap_handler when add > > > > > the entry to list. > > > > > > > > > > Assign the freed pages/page_ptr to NULL to catch possible > > > > > use after free with NULL pointer access. > > > > > > > > > > Signed-off-by: Kassey Li <quic_yingangl@quicinc.com> > > > > > --- > > > > > drivers/android/binder_alloc.c | 5 ++++- > > > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > > > What commit id does this fix? > > > > > > there is no specific commit id this change going to fix. > > > > > > it is a follow up for commit > > > 19c987241ca1216a51118b2bd0185b8bc5081783 binder: separate out binder_alloc > > > functions (mutex lock added for list access in alloc/free) > > > f2517eb76f1f2f7f89761f9db2b202e89931738c android: binder: Add global lru > > > shrinker to binder (set page->page_ptr = NULL;) > > > > > > the background to raise this change that we are easy hit below crash in > > > monkey test: > > > > > > where a wrong end is passing to > > > binder_update_page_range, thus calculate a weird index > > > for > > > page = &alloc->pages[index] > > > > Obviously it is a fix for some commit, please list that here. > > ok, please kindly review this patch description according your suggest, i > can re-send v2 patch again. > > commit 16aaeb8556ff4eb75823c56773ee82b06bac44a0 (HEAD -> master) > Author: Kassey Li <quic_yingangl@quicinc.com> > Date: Thu Sep 28 10:42:52 2023 +0800 > > binder: add mutex_lock for mmap and NULL when free > > -Enforce alloc->mutex in binder_alloc_mmap_handler when add > the entry to list. > > -Assign the freed pages/page_ptr to NULL to catch possible > use after free with NULL pointer access.
Odd indentation :(
> Fixes: 19c987241ca1 ("binder: separate out binder_alloc functions") > Fixes: f2517eb76f1f ("android: binder: Add global lru shrinker to > binder") > Signed-off-by: Kassey Li <quic_yingangl@quicinc.com>
Looks better than before, thanks.
greg k-h
| |