path: root/mm
diff options
authorRick Edgecombe <rick.p.edgecombe@intel.com>2019-05-27 14:10:57 -0700
committerIngo Molnar <mingo@kernel.org>2019-06-03 11:47:25 +0200
commit8e41f8726dcf423621e2b6938d015b9796f6f676 (patch)
tree2f698e3037318c76be78720d0e533bcc12847a42 /mm
parentf2c7c76c5d0a443053e94adb9f0918fa2fb85c3a (diff)
mm/vmalloc: Fix calculation of direct map addr range
The calculation of the direct map address range to flush was wrong. This could cause the RO direct map alias to not get flushed. Today this shouldn't be a problem because this flush is only needed on x86 right now and the spurious fault handler will fix cached RO->RW translations. In the future though, it could cause the permissions to remain RO in the TLB for the direct map alias, and then the page would return from the page allocator to some other component as RO and cause a crash. So fix fix the address range calculation so the flush will include the direct map range. Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Meelis Roos <mroos@linux.ee> Cc: Nadav Amit <namit@vmware.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 868b104d7379 ("mm/vmalloc: Add flag for freeing of special permsissions") Link: https://lkml.kernel.org/r/20190527211058.2729-2-rick.p.edgecombe@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'mm')
1 files changed, 5 insertions, 5 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 7350a124524b..93b2dca2aadb 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2123,7 +2123,6 @@ static inline void set_area_direct_map(const struct vm_struct *area,
/* Handle removing and resetting vm mappings related to the vm_struct. */
static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
- unsigned long addr = (unsigned long)area->addr;
unsigned long start = ULONG_MAX, end = 0;
int flush_reset = area->flags & VM_FLUSH_RESET_PERMS;
int i;
@@ -2135,8 +2134,8 @@ static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
* execute permissions, without leaving a RW+X window.
- set_memory_nx(addr, area->nr_pages);
- set_memory_rw(addr, area->nr_pages);
+ set_memory_nx((unsigned long)area->addr, area->nr_pages);
+ set_memory_rw((unsigned long)area->addr, area->nr_pages);
@@ -2160,9 +2159,10 @@ static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
* the vm_unmap_aliases() flush includes the direct map.
for (i = 0; i < area->nr_pages; i++) {
- if (page_address(area->pages[i])) {
+ unsigned long addr = (unsigned long)page_address(area->pages[i]);
+ if (addr) {
start = min(addr, start);
- end = max(addr, end);
+ end = max(addr + PAGE_SIZE, end);