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authorLinus Torvalds <torvalds@linux-foundation.org>2019-10-26 15:17:54 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2019-10-26 15:17:54 -0400
commita03885d596a622e25f655e280a3fcd9e754a37bd (patch)
tree3f39e6949a3354e23c41facebb6304ed4739c889 /drivers
parent0ecdd78c75b76a38fdd3064157adb4a091e5bbee (diff)
parent45d02f79b539073b76077836871de6b674e36eb4 (diff)
Merge tag 'char-misc-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull binder fix from Greg KH: "This is a single binder fix to resolve a reported issue by Jann. It's been in linux-next for a while with no reported issues" * tag 'char-misc-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: binder: Don't modify VMA bounds in ->mmap handler
Diffstat (limited to 'drivers')
-rw-r--r--drivers/android/binder.c7
-rw-r--r--drivers/android/binder_alloc.c6
2 files changed, 4 insertions, 9 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 5b9ac2122e89..265d9dd46a5e 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -97,10 +97,6 @@ DEFINE_SHOW_ATTRIBUTE(proc);
#define SZ_1K 0x400
#endif
-#ifndef SZ_4M
-#define SZ_4M 0x400000
-#endif
-
#define FORBIDDEN_MMAP_FLAGS (VM_WRITE)
enum {
@@ -5177,9 +5173,6 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
if (proc->tsk != current->group_leader)
return -EINVAL;
- if ((vma->vm_end - vma->vm_start) > SZ_4M)
- vma->vm_end = vma->vm_start + SZ_4M;
-
binder_debug(BINDER_DEBUG_OPEN_CLOSE,
"%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n",
__func__, proc->pid, vma->vm_start, vma->vm_end,
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index d42a8b2f636a..eb76a823fbb2 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -22,6 +22,7 @@
#include <asm/cacheflush.h>
#include <linux/uaccess.h>
#include <linux/highmem.h>
+#include <linux/sizes.h>
#include "binder_alloc.h"
#include "binder_trace.h"
@@ -689,7 +690,9 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc,
alloc->buffer = (void __user *)vma->vm_start;
mutex_unlock(&binder_alloc_mmap_lock);
- alloc->pages = kcalloc((vma->vm_end - vma->vm_start) / PAGE_SIZE,
+ alloc->buffer_size = min_t(unsigned long, vma->vm_end - vma->vm_start,
+ SZ_4M);
+ alloc->pages = kcalloc(alloc->buffer_size / PAGE_SIZE,
sizeof(alloc->pages[0]),
GFP_KERNEL);
if (alloc->pages == NULL) {
@@ -697,7 +700,6 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc,
failure_string = "alloc page array";
goto err_alloc_pages_failed;
}
- alloc->buffer_size = vma->vm_end - vma->vm_start;
buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
if (!buffer) {