Messages in this thread | | | Date | Mon, 20 Jun 2022 12:17:56 +0200 | From | Greg KH <> | Subject | Re: [PATCH 5.15] mm: validate buddy page before using |
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On Fri, Jun 17, 2022 at 12:17:45AM +0800, Xianting Tian wrote: > Commit 787af64d05cd ("mm: page_alloc: validate buddy before check its migratetype.") > fixes a bug in 1dd214b8f21c and there is a similar bug in d9dddbf55667 that > can be fixed in a similar way too. > > In unset_migratetype_isolate(), we also need the fix, so move page_is_buddy() > from mm/page_alloc.c to mm/internal.h > > In addition, for RISC-V arch the first 2MB RAM could be reserved for opensbi, > so it would have pfn_base=512 and mem_map began with 512th PFN when > CONFIG_FLATMEM=y. > But __find_buddy_pfn algorithm thinks the start pfn 0, it could get 0 pfn or > less than the pfn_base value. We need page_is_buddy() to verify the buddy to > prevent accessing an invalid buddy. > > Fixes: d9dddbf55667 ("mm/page_alloc: prevent merging between isolated and other pageblocks") > Cc: stable@vger.kernel.org > Reported-by: zjb194813@alibaba-inc.com > Reported-by: tianhu.hh@alibaba-inc.com > Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com> > --- > mm/internal.h | 34 ++++++++++++++++++++++++++++++++++ > mm/page_alloc.c | 37 +++---------------------------------- > mm/page_isolation.c | 3 ++- > 3 files changed, 39 insertions(+), 35 deletions(-)
What is the commit id of this in Linus's tree?
thanks,
greg k-h
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