On Sat, Dec 04, 2021 at 08:54:08AM -0500, Nathaniel McCallum wrote:
> We are seeing a possible regression between 5.14.18 and 5.15.6. Our
> trace logging shows the following output:
>
> enclave location: 00007f3c00000000-00007f3c80000000
> creating enclave: Secs { size: 2147483648, baseaddr: 139895674765312,
> ssaframesize: 1, miscselect: (empty), attributes: Attributes {
> features: MODE64BIT, xfrm: X87 | SSE }, pid: 0, svn: 0 }
> adding pages: 00007f3c00000000-00007f3c00004000 R
> adding pages: 00007f3c00004000-00007f3c0000c000 RW
> adding pages: 00007f3c0000c000-00007f3c00039000 RX
> adding pages: 00007f3c00201000-00007f3c003fc000 RW
> adding pages: 00007f3c003fc000-00007f3c003fd000 T
> adding pages: 00007f3c003fd000-00007f3c00400000 RW
> adding pages: 00007f3c00400000-00007f3c00401000 R
> adding pages: 00007f3c00401000-00007f3c00402000 RX
> adding pages: 00007f3c00402000-00007f3c00403000 R
> adding pages: 00007f3c00403000-00007f3c00404000 RW
> enclave initialized
> remapping: 00007f3c00000000-00007f3c00004000 R
> remapping: 00007f3c00004000-00007f3c0000c000 RW
> remapping: 00007f3c0000c000-00007f3c00039000 RX
> Error: Operation not permitted (os error 1)
>
> Using strace shows this:
> ...
> mmap(0x7f6e80000000, 16384, PROT_READ, MAP_SHARED|MAP_FIXED, 3, 0) =
> 0x7f6e80000000
> mmap(0x7f6e80004000, 32768, PROT_READ|PROT_WRITE,
> MAP_SHARED|MAP_FIXED, 3, 0) = 0x7f6e80004000
> mmap(0x7f6e8000c000, 184320, PROT_READ|PROT_EXEC,
> MAP_SHARED|MAP_FIXED, 3, 0) = -1 EPERM (Operation not permitted)
>
> We've followed the selftest structure pretty closely. The first two
> remapping calls succeed, but the third one fails. This works on
> 5.14.18, but fails on 5.15.6.
What are the mount options of /dev?
/Jarkko
