summaryrefslogtreecommitdiff
path: root/arch/powerpc/include
diff options
context:
space:
mode:
authorChristophe Leroy <christophe.leroy@c-s.fr>2020-03-07 10:09:15 +0000
committerMichael Ellerman <mpe@ellerman.id.au>2020-03-13 21:13:05 +1100
commitcc6f0e39000900e5dd1448103a9571f0eccd7d4e (patch)
tree09f51e44728fe42929e2fd9e6aeff1a62890c4fb /arch/powerpc/include
parent819723a8a2fb66678fe15d177ae56af38163f364 (diff)
powerpc/32: Fix missing NULL pmd check in virt_to_kpte()
Commit 2efc7c085f05 ("powerpc/32: drop get_pteptr()"), replaced get_pteptr() by virt_to_kpte(). But virt_to_kpte() lacks a NULL pmd check and returns an invalid non NULL pointer when there is no page table. Reported-by: Nick Desaulniers <ndesaulniers@google.com> Fixes: 2efc7c085f05 ("powerpc/32: drop get_pteptr()") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b1177cdfc6af74a3e277bba5d9e708c4b3315ebe.1583575707.git.christophe.leroy@c-s.fr
Diffstat (limited to 'arch/powerpc/include')
-rw-r--r--arch/powerpc/include/asm/pgtable.h4
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
index b80bfd41828d..b1f1d5339735 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h
@@ -54,7 +54,9 @@ static inline pmd_t *pmd_ptr_k(unsigned long va)
static inline pte_t *virt_to_kpte(unsigned long vaddr)
{
- return pte_offset_kernel(pmd_ptr_k(vaddr), vaddr);
+ pmd_t *pmd = pmd_ptr_k(vaddr);
+
+ return pmd_none(*pmd) ? NULL : pte_offset_kernel(pmd, vaddr);
}
#endif