diff options
| author | Deepak Gupta <debug@rivosinc.com> | 2026-01-25 21:09:53 -0700 |
|---|---|---|
| committer | Paul Walmsley <pjw@kernel.org> | 2026-01-25 21:09:53 -0700 |
| commit | f56ffb8ada46aae61580905d93c31e4006572240 (patch) | |
| tree | 798f4b49d3edae4af593fb5dbc89ca3824650e71 /arch/riscv/include | |
| parent | 6c7559f22b6fcb2d4b52c445434c71ade36b004c (diff) | |
riscv/mm: manufacture shadow stack ptes
This patch implements the creation of a shadow stack pte on
riscv. Creating shadow stack PTE on riscv means clearing RWX and then
setting W=1.
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6
Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com>
Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-7-b55691eacf4f@rivosinc.com
[pjw@kernel.org: cleaned up patch description]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Diffstat (limited to 'arch/riscv/include')
| -rw-r--r-- | arch/riscv/include/asm/pgtable.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index b384a1a9327e..153a692a5640 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -456,6 +456,11 @@ static inline pte_t pte_mkwrite_novma(pte_t pte) return __pte(pte_val(pte) | _PAGE_WRITE); } +static inline pte_t pte_mkwrite_shstk(pte_t pte) +{ + return __pte((pte_val(pte) & ~(_PAGE_LEAF)) | _PAGE_WRITE); +} + /* static inline pte_t pte_mkexec(pte_t pte) */ static inline pte_t pte_mkdirty(pte_t pte) @@ -839,6 +844,11 @@ static inline pmd_t pmd_mkwrite_novma(pmd_t pmd) return pte_pmd(pte_mkwrite_novma(pmd_pte(pmd))); } +static inline pmd_t pmd_mkwrite_shstk(pmd_t pte) +{ + return __pmd((pmd_val(pte) & ~(_PAGE_LEAF)) | _PAGE_WRITE); +} + static inline pmd_t pmd_wrprotect(pmd_t pmd) { return pte_pmd(pte_wrprotect(pmd_pte(pmd))); |