lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Sat, 16 Dec 2017 01:59:17 +0100 (CET) From: Thomas Gleixner <tglx@...utronix.de> To: LKML <linux-kernel@...r.kernel.org> cc: x86@...nel.org, Peter Zijlstra <peterz@...radead.org>, Dave Hansen <dave.hansen@...ux.intel.com>, keescook@...gle.com Subject: [PATCH] x86/mm/dump_pagetables: Check PAGE_PRESENT for real The check for a present page in printk_prot(): if (!pgprot_val(prot)) { /* Not present */ is bogus. If a PTE is set to PAGE_NONE then the pgprot_val is not zero and the entry is decoded in bogus ways, e.g. as RX GLB. That is confusing when analyzing mapping correctness. Check for the present bit to make an informed decision. Signed-off-by: Thomas Gleixner <tglx@...utronix.de> --- arch/x86/mm/dump_pagetables.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -140,7 +140,7 @@ static void printk_prot(struct seq_file static const char * const level_name[] = { "cr3", "pgd", "p4d", "pud", "pmd", "pte" }; - if (!pgprot_val(prot)) { + if (!(pgprot_val(prot) & _PAGE_PRESENT)) { /* Not present */ pt_dump_cont_printf(m, dmsg, " "); } else {
Powered by blists - more mailing lists