1. 13 Feb, 2014 2 commits
    • Alex Williamson's avatar
      intel-iommu: fix off-by-one in pagetable freeing · 55931654
      Alex Williamson authored
      commit 08336fd2 upstream.
      
      dma_pte_free_level() has an off-by-one error when checking whether a pte
      is completely covered by a range.  Take for example the case of
      attempting to free pfn 0x0 - 0x1ff, ie.  512 entries covering the first
      2M superpage.
      
      The level_size() is 0x200 and we test:
      
        static void dma_pte_free_level(...
      	...
      
      	if (!(0 > 0 || 0x1ff < 0 + 0x200)) {
      		...
      	}
      
      Clearly the 2nd test is true, which means we fail to take the branch to
      clear and free the pagetable entry.  As a result, we're leaking
      pagetables and failing to install new pages over the range.
      
      This was found with a PCI device assigned to a QEMU guest using vfio-pci
      without a VGA device present.  The first 1M of guest address space is
      mapped with various combinations of 4K pages, but eventually the range
      is entirely freed and replaced with a 2M contiguous mapping.
      intel-iommu errors out with something like:
      
        ERROR: DMA PTE for vPFN 0x0 already set (to 5c2b8003 not 849c00083)
      
      In this case 5c2b8003 is the pointer to the previous leaf page that was
      neither freed nor cleared and 849c00083 is the superpage entry that
      we're trying to replace it with.
      Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Joerg Roedel <joro@8bytes.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      55931654
    • Tetsuo Handa's avatar
      SELinux: Fix memory leak upon loading policy · ef609edc
      Tetsuo Handa authored
      commit 8ed81460 upstream.
      
      Hello.
      
      I got below leak with linux-3.10.0-54.0.1.el7.x86_64 .
      
      [  681.903890] kmemleak: 5538 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
      
      Below is a patch, but I don't know whether we need special handing for undoing
      ebitmap_set_bit() call.
      ----------
      >>From fe97527a90fe95e2239dfbaa7558f0ed559c0992 Mon Sep 17 00:00:00 2001
      From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Date: Mon, 6 Jan 2014 16:30:21 +0900
      Subject: SELinux: Fix memory leak upon loading policy
      
      Commit 2463c26d "SELinux: put name based create rules in a hashtable" did not
      check return value from hashtab_insert() in filename_trans_read(). It leaks
      memory if hashtab_insert() returns error.
      
        unreferenced object 0xffff88005c9160d0 (size 8):
          comm "systemd", pid 1, jiffies 4294688674 (age 235.265s)
          hex dump (first 8 bytes):
            57 0b 00 00 6b 6b 6b a5                          W...kkk.
          backtrace:
            [<ffffffff816604ae>] kmemleak_alloc+0x4e/0xb0
            [<ffffffff811cba5e>] kmem_cache_alloc_trace+0x12e/0x360
            [<ffffffff812aec5d>] policydb_read+0xd1d/0xf70
            [<ffffffff812b345c>] security_load_policy+0x6c/0x500
            [<ffffffff812a623c>] sel_write_load+0xac/0x750
            [<ffffffff811eb680>] vfs_write+0xc0/0x1f0
            [<ffffffff811ec08c>] SyS_write+0x4c/0xa0
            [<ffffffff81690419>] system_call_fastpath+0x16/0x1b
            [<ffffffffffffffff>] 0xffffffffffffffff
      
      However, we should not return EEXIST error to the caller, or the systemd will
      show below message and the boot sequence freezes.
      
        systemd[1]: Failed to load SELinux policy. Freezing.
      Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Acked-by: default avatarEric Paris <eparis@redhat.com>
      Signed-off-by: default avatarPaul Moore <pmoore@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      ef609edc
  2. 06 Feb, 2014 37 commits
  3. 29 Jan, 2014 1 commit