On 2/23/22 00:33, Michal Hocko wrote: > On Tue 22-02-22 13:53:56, Mike Kravetz wrote: >> On 2/21/22 23:47, Michal Hocko wrote: >> How about adding this note to the commit message? >> >> Note: these routines take a user specified value used as an index ONCE >> during the boot process. As a result, they can not be used as a general >> method of exploitation. Code changes are being made to eliminate warnings. > > This would help but the question whether the change is worth remains. > Does this change have any other advantage than silencing the warning? > Silencing the warnings was the primary motivation for the change. If Dan has a plan to change smatch so that they are silenced for __init functions, then it would be better to not make the changes to use array_index_nospec. While making the changes, I shuffled the code a little and did not immediately notice that it also 'fixes' an overflow/truncation issue when assigning an unsigned long to int as addressed in [1]. We should probably make this change whether or not we use array_index_nospec to silence warnings. [1] https://lore.kernel.org/linux-mm/20220209134018.8242-1-liuyuntao10@xxxxxxxxxx/ Thanks for your comments and suggestions! -- Mike Kravetz
