| Message ID | 20220528014132.91052-1-heinrich.schuchardt@canonical.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | riscv: read-only pages should not be writable | expand |
On Sat, 28 May 2022 at 03:41, Heinrich Schuchardt <heinrich.schuchardt@canonical.com> wrote: > > If EFI pages are marked as read-only, > we should remove the _PAGE_WRITE flag. > > The current code overwrites an unused value. > > Fixes: b91540d52a08b ("RISC-V: Add EFI runtime services") > Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com> > --- > arch/riscv/kernel/efi.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/riscv/kernel/efi.c b/arch/riscv/kernel/efi.c > index 024159298231..1aa540350abd 100644 > --- a/arch/riscv/kernel/efi.c > +++ b/arch/riscv/kernel/efi.c > @@ -65,7 +65,7 @@ static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data) > > if (md->attribute & EFI_MEMORY_RO) { > val = pte_val(pte) & ~_PAGE_WRITE; > - val = pte_val(pte) | _PAGE_READ; > + val |= _PAGE_READ; > pte = __pte(val); > } > if (md->attribute & EFI_MEMORY_XP) { > -- > 2.36.1 > Thanks Heinrich Queued in efi/urgent.
On 5/28/22 11:13, Ard Biesheuvel wrote: > On Sat, 28 May 2022 at 03:41, Heinrich Schuchardt > <heinrich.schuchardt@canonical.com> wrote: >> >> If EFI pages are marked as read-only, >> we should remove the _PAGE_WRITE flag. >> >> The current code overwrites an unused value. >> >> Fixes: b91540d52a08b ("RISC-V: Add EFI runtime services") >> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com> >> --- >> arch/riscv/kernel/efi.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/riscv/kernel/efi.c b/arch/riscv/kernel/efi.c >> index 024159298231..1aa540350abd 100644 >> --- a/arch/riscv/kernel/efi.c >> +++ b/arch/riscv/kernel/efi.c >> @@ -65,7 +65,7 @@ static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data) >> >> if (md->attribute & EFI_MEMORY_RO) { >> val = pte_val(pte) & ~_PAGE_WRITE; >> - val = pte_val(pte) | _PAGE_READ; >> + val |= _PAGE_READ; >> pte = __pte(val); >> } >> if (md->attribute & EFI_MEMORY_XP) { >> -- >> 2.36.1 >> > > Thanks Heinrich > > Queued in efi/urgent. I guess this should also be down-ported to 5.15 and 5.10. Best regards Heinrich
diff --git a/arch/riscv/kernel/efi.c b/arch/riscv/kernel/efi.c index 024159298231..1aa540350abd 100644 --- a/arch/riscv/kernel/efi.c +++ b/arch/riscv/kernel/efi.c @@ -65,7 +65,7 @@ static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data) if (md->attribute & EFI_MEMORY_RO) { val = pte_val(pte) & ~_PAGE_WRITE; - val = pte_val(pte) | _PAGE_READ; + val |= _PAGE_READ; pte = __pte(val); } if (md->attribute & EFI_MEMORY_XP) {
If EFI pages are marked as read-only, we should remove the _PAGE_WRITE flag. The current code overwrites an unused value. Fixes: b91540d52a08b ("RISC-V: Add EFI runtime services") Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com> --- arch/riscv/kernel/efi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)