diff options
| author | Thomas Gleixner <[email protected]> | 2019-04-15 10:46:07 +0200 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2019-04-16 09:42:10 +0200 |
| commit | 510bb96fe5b3480b4b22d815786377e54cb701e7 (patch) | |
| tree | afdfca77448b5acac50a2fcfba1c2d2d77d6c73b | |
| parent | 6a03469a1edc94da52b65478f1e00837add869a3 (diff) | |
x86/mm: Prevent bogus warnings with "noexec=off"
Xose Vazquez Perez reported boot warnings when NX is disabled on the kernel command line.
__early_set_fixmap() triggers this warning:
attempted to set unsupported pgprot: 8000000000000163
bits: 8000000000000000
supported: 7fffffffffffffff
WARNING: CPU: 0 PID: 0 at arch/x86/include/asm/pgtable.h:537
__early_set_fixmap+0xa2/0xff
because it uses __default_kernel_pte_mask to mask out unsupported bits.
Use __supported_pte_mask instead.
Disabling NX on the command line also triggers the NX warning in the page
table mapping check:
WARNING: CPU: 1 PID: 1 at arch/x86/mm/dump_pagetables.c:262 note_page+0x2ae/0x650
....
Make the warning depend on NX set in __supported_pte_mask.
Reported-by: Xose Vazquez Perez <[email protected]>
Tested-by: Xose Vazquez Perez <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rik van Riel <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | arch/x86/mm/dump_pagetables.c | 3 | ||||
| -rw-r--r-- | arch/x86/mm/ioremap.c | 2 |
2 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index ee8f8ab46941..c0309ea9abee 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -259,7 +259,8 @@ static void note_wx(struct pg_state *st) #endif /* Account the WX pages */ st->wx_pages += npages; - WARN_ONCE(1, "x86/mm: Found insecure W+X mapping at address %pS\n", + WARN_ONCE(__supported_pte_mask & _PAGE_NX, + "x86/mm: Found insecure W+X mapping at address %pS\n", (void *)st->start_address); } diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 0029604af8a4..dd73d5d74393 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -825,7 +825,7 @@ void __init __early_set_fixmap(enum fixed_addresses idx, pte = early_ioremap_pte(addr); /* Sanitize 'prot' against any unsupported bits: */ - pgprot_val(flags) &= __default_kernel_pte_mask; + pgprot_val(flags) &= __supported_pte_mask; if (pgprot_val(flags)) set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags)); |