3.0-stable patches

added patches:
	3.0-mm-Hold-a-file-reference-in-madvise_remove.patch

diff --git a/queue-3.0/3.0-mm-Hold-a-file-reference-in-madvise_remove.patch b/queue-3.0/3.0-mm-Hold-a-file-reference-in-madvise_remove.patch
new file mode 100644 (file)
index 0000000..f75dbce
--- /dev/null
+++ b/queue-3.0/3.0-mm-Hold-a-file-reference-in-madvise_remove.patch
@@ -0,0 +1,80 @@
+From a88e489ab2bd7d0b50a8782b948a58b38d4d239a Mon Sep 17 00:00:00 2001
+Message-Id: <a88e489ab2bd7d0b50a8782b948a58b38d4d239a.1342049669.git.luto@amacapital.net>
+From: Andy Lutomirski <luto@amacapital.net>
+Date: Thu, 5 Jul 2012 16:00:11 -0700
+Subject: mm: Hold a file reference in madvise_remove
+
+From: Andy Lutomirski <luto@amacapital.net>
+
+commit 9ab4233dd08036fe34a89c7dc6f47a8bf2eb29eb upstream.
+
+Otherwise the code races with munmap (causing a use-after-free
+of the vma) or with close (causing a use-after-free of the struct
+file).
+
+The bug was introduced by commit 90ed52ebe481 ("[PATCH] holepunch: fix
+mmap_sem i_mutex deadlock")
+
+[bwh: Backported to 3.2:
+ - Adjust context
+ - madvise_remove() calls vmtruncate_range(), not do_fallocate()]
+[luto: Backported to 3.0: Adjust context]
+
+Cc: Hugh Dickins <hugh@veritas.com>
+Cc: Miklos Szeredi <mszeredi@suse.cz>
+Cc: Badari Pulavarty <pbadari@us.ibm.com>
+Cc: Nick Piggin <npiggin@suse.de>
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+Signed-off-by: Andy Lutomirski <luto@amacapital.net>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ mm/madvise.c |   16 +++++++++++++---
+ 1 file changed, 13 insertions(+), 3 deletions(-)
+
+--- a/mm/madvise.c
++++ b/mm/madvise.c
+@@ -13,6 +13,7 @@
+ #include <linux/hugetlb.h>
+ #include <linux/sched.h>
+ #include <linux/ksm.h>
++#include <linux/file.h>
+ 
+ /*
+  * Any behaviour which results in changes to the vma->vm_flags needs to
+@@ -197,14 +198,16 @@ static long madvise_remove(struct vm_are
+       struct address_space *mapping;
+       loff_t offset, endoff;
+       int error;
++      struct file *f;
+ 
+       *prev = NULL;   /* tell sys_madvise we drop mmap_sem */
+ 
+       if (vma->vm_flags & (VM_LOCKED|VM_NONLINEAR|VM_HUGETLB))
+               return -EINVAL;
+ 
+-      if (!vma->vm_file || !vma->vm_file->f_mapping
+-              || !vma->vm_file->f_mapping->host) {
++      f = vma->vm_file;
++
++      if (!f || !f->f_mapping || !f->f_mapping->host) {
+                       return -EINVAL;
+       }
+ 
+@@ -218,9 +221,16 @@ static long madvise_remove(struct vm_are
+       endoff = (loff_t)(end - vma->vm_start - 1)
+                       + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+ 
+-      /* vmtruncate_range needs to take i_mutex and i_alloc_sem */
++      /*
++       * vmtruncate_range may need to take i_mutex and i_alloc_sem.
++       * We need to explicitly grab a reference because the vma (and
++       * hence the vma's reference to the file) can go away as soon as
++       * we drop mmap_sem.
++       */
++      get_file(f);
+       up_read(&current->mm->mmap_sem);
+       error = vmtruncate_range(mapping->host, offset, endoff);
++      fput(f);
+       down_read(&current->mm->mmap_sem);
+       return error;
+ }

diff --git a/queue-3.0/series b/queue-3.0/series
index 5610ce510339c0a35b585585c7fe557c3c4d5c4c..d4a413a9501a8a148e912ba50cfb5d6f82524c58 100644 (file)
--- a/queue-3.0/series
+++ b/queue-3.0/series
@@ -63,3 +63,4 @@ memory-hotplug-fix-invalid-memory-access-caused-by-stale-kswapd-pointer.patch
 drivers-rtc-rtc-mxc.c-fix-irq-enabled-interrupts-warning.patch
 mm-thp-abort-compaction-if-migration-page-cannot-be-charged-to-memcg.patch
 fs-ramfs-file-nommu-add-setpageuptodate.patch
+3.0-mm-Hold-a-file-reference-in-madvise_remove.patch