On 05/03/2018 10:32 PM, Davidlohr Bueso wrote: > Hi, > > These patches fix two issues reported[1] a while back by Joe and Andrea > around how shmat(2) behaves with nil-page. > > The first reverts a commit that it was incorrectly thought that mapping > nil-page (address=0) was a no no with MAP_FIXED. This is not the case, > with the exception of SHM_REMAP; which is address in the second patch. Can you add appropriate Fixes: tags if possible? I guess patch 1 is clear, dunno about patch 2... > I chose two patches because it is easier to backport and it explicitly > reverts bogus behaviour. Both patches ought to be in -stable and ltp > testcases need updated (the added testcase around the cve can be modified > to just test for SHM_RND|SHM_REMAP). CC'd ltp so they know :) Thanks, Vlastimil > > [1] lkml.kernel.org/r/20180430172152.nfa564pvgpk3ut7p@linux-n805 > > Thanks! > > Davidlohr Bueso (2): > Revert "ipc/shm: Fix shmat mmap nil-page protection" > ipc/shm: fix shmat() nil address after round-down when remapping > > ipc/shm.c | 19 +++++++++++-------- > 1 file changed, 11 insertions(+), 8 deletions(-) >
