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authorLinus Torvalds <torvalds@linux-foundation.org>2016-02-04 14:09:55 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-02-04 14:09:55 -0800
commitdf48ab3c2f5ffca88b7803ffbadd074bd5a0a2ef (patch)
tree515c7d05e99f21af284705f359b6d7bc442a6649 /arch
parent5787c25240c92df25f34c1abb7f76a96d8615034 (diff)
parent3e275c64a973ba1554ef87f76c9f0f5b5221ab14 (diff)
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon: "Nothing particularly interesting here, but all important fixes nonetheless: - Add missing PAN toggling in the futex code - Fix missing #include that briefly caused issues in -next - Allow changing of vmalloc permissions with set_memory_* (used by bpf)" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: asm: Explicitly include linux/personality.h in asm/page.h arm64: futex.h: Add missing PAN toggling arm64: allow vmalloc regions to be set with set_memory_*
Diffstat (limited to 'arch')
-rw-r--r--arch/arm64/include/asm/futex.h2
-rw-r--r--arch/arm64/include/asm/page.h1
-rw-r--r--arch/arm64/mm/pageattr.c23
3 files changed, 22 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/futex.h b/arch/arm64/include/asm/futex.h
index 007a69fc4f40..5f3ab8c1db55 100644
--- a/arch/arm64/include/asm/futex.h
+++ b/arch/arm64/include/asm/futex.h
@@ -121,6 +121,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
return -EFAULT;
asm volatile("// futex_atomic_cmpxchg_inatomic\n"
+ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN, CONFIG_ARM64_PAN)
" prfm pstl1strm, %2\n"
"1: ldxr %w1, %2\n"
" sub %w3, %w1, %w4\n"
@@ -137,6 +138,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
" .align 3\n"
" .quad 1b, 4b, 2b, 4b\n"
" .popsection\n"
+ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN)
: "+r" (ret), "=&r" (val), "+Q" (*uaddr), "=&r" (tmp)
: "r" (oldval), "r" (newval), "Ir" (-EFAULT)
: "memory");
diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h
index 9b2f5a9d019d..ae615b9d9a55 100644
--- a/arch/arm64/include/asm/page.h
+++ b/arch/arm64/include/asm/page.h
@@ -39,6 +39,7 @@
#ifndef __ASSEMBLY__
+#include <linux/personality.h> /* for READ_IMPLIES_EXEC */
#include <asm/pgtable-types.h>
extern void __cpu_clear_user_page(void *p, unsigned long user);
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index cf6240741134..0795c3a36d8f 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -14,6 +14,7 @@
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sched.h>
+#include <linux/vmalloc.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
@@ -44,6 +45,7 @@ static int change_memory_common(unsigned long addr, int numpages,
unsigned long end = start + size;
int ret;
struct page_change_data data;
+ struct vm_struct *area;
if (!PAGE_ALIGNED(addr)) {
start &= PAGE_MASK;
@@ -51,10 +53,23 @@ static int change_memory_common(unsigned long addr, int numpages,
WARN_ON_ONCE(1);
}
- if (start < MODULES_VADDR || start >= MODULES_END)
- return -EINVAL;
-
- if (end < MODULES_VADDR || end >= MODULES_END)
+ /*
+ * Kernel VA mappings are always live, and splitting live section
+ * mappings into page mappings may cause TLB conflicts. This means
+ * we have to ensure that changing the permission bits of the range
+ * we are operating on does not result in such splitting.
+ *
+ * Let's restrict ourselves to mappings created by vmalloc (or vmap).
+ * Those are guaranteed to consist entirely of page mappings, and
+ * splitting is never needed.
+ *
+ * So check whether the [addr, addr + size) interval is entirely
+ * covered by precisely one VM area that has the VM_ALLOC flag set.
+ */
+ area = find_vm_area((void *)addr);
+ if (!area ||
+ end > (unsigned long)area->addr + area->size ||
+ !(area->flags & VM_ALLOC))
return -EINVAL;
if (!numpages)