allowed mmap of /dev/kmem?

[grsecuser]

I am using grsecurity-2.1.6-2.4.31-200506141150. Over a year ago I downloaded a regression test from grsec cvs that tested writing to /dev/kmem, etc (it seems to have been removed from CVS in the meantime). I noticed after I upgraded that it says

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Testing denied write of /dev/mem... : PASSED
Testing denied mmap write of /dev/kmem... : FAILED
Testing denied open of /dev/port... : PASSED
Testing denied write of /dev/kmem... : PASSED
Testing denied mmap write of /dev/kmem... : FAILED


I think the first "Testing denied mmap write of /dev/kmem" should say "Testing denied mmap write of /dev/mem". The mmap testing code is

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fd = open("/dev/kmem", O_RDWR);

retp = mmap(NULL, 1000, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);

close(fd);
       
if (retp == MAP_FAILED)
    printf("PASSED\n");
else
    printf("FAILED\n");


On a machine running 2.1.5-2.4.30-200504082027, all the tests pass as expected.

Is this something I should be concerned about? I saw mention of kmem changes related to ATI video cards in the announcement, but this machine has an S3 card in it.

Thanks!

[spender]

The regression test was wrong. It tested by writing to an area of physical memory not involved with the kernel image which needs to be written to by some video cards. I've fixed the regression test.

-Brad