diff options
| author | Juergen Gross <jgross@suse.com> | 2024-04-12 17:12:56 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2024-04-14 22:16:27 +0200 |
| commit | d29dc5177b7d011377ecf648551027c94d2b1386 (patch) | |
| tree | 6cb7e4e4b6b34292032b5e1292504a2efa7398ce /arch/x86 | |
| parent | x86/pat: Introduce lookup_address_in_pgd_attr() (diff) | |
| download | linux-d29dc5177b7d011377ecf648551027c94d2b1386.tar.xz linux-d29dc5177b7d011377ecf648551027c94d2b1386.zip | |
x86/mm: Use lookup_address_in_pgd_attr() in show_fault_oops()
Fix show_fault_oops() to not only look at the leaf PTE for detecting
NX violations, but to use the effective NX value returned by
lookup_address_in_pgd_attr() instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240412151258.9171-3-jgross@suse.com
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/mm/fault.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 622d12ec7f08..6b2ca8ba75b8 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -514,18 +514,19 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad if (error_code & X86_PF_INSTR) { unsigned int level; + bool nx, rw; pgd_t *pgd; pte_t *pte; pgd = __va(read_cr3_pa()); pgd += pgd_index(address); - pte = lookup_address_in_pgd(pgd, address, &level); + pte = lookup_address_in_pgd_attr(pgd, address, &level, &nx, &rw); - if (pte && pte_present(*pte) && !pte_exec(*pte)) + if (pte && pte_present(*pte) && (!pte_exec(*pte) || nx)) pr_crit("kernel tried to execute NX-protected page - exploit attempt? (uid: %d)\n", from_kuid(&init_user_ns, current_uid())); - if (pte && pte_present(*pte) && pte_exec(*pte) && + if (pte && pte_present(*pte) && pte_exec(*pte) && !nx && (pgd_flags(*pgd) & _PAGE_USER) && (__read_cr4() & X86_CR4_SMEP)) pr_crit("unable to execute userspace code (SMEP?) (uid: %d)\n", |