1. 07 Jun, 2016 31 commits
  2. 05 Jun, 2016 7 commits
    • Linus Torvalds's avatar
      Linux 4.7-rc2 · af8c34ce
      Linus Torvalds authored
      af8c34ce
    • Linus Torvalds's avatar
      Merge branch 'parisc-4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux · 5975b2c0
      Linus Torvalds authored
      Pull parisc fixes from Helge Deller:
      
       - Fix printk time stamps on SMP systems which got wrong due to a patch
         which was added during the merge window
      
       - Fix two bugs in the stack backtrace code: Races in module unloading
         and possible invalid accesses to memory due to wrong instruction
         decoding (Mikulas Patocka)
      
       - Fix userspace crash when syscalls access invalid unaligned userspace
         addresses.  Those syscalls will now return EFAULT as expected.
         (tagged for stable kernel series)
      
      * 'parisc-4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
        parisc: Move die_if_kernel() prototype into traps.h header
        parisc: Fix pagefault crash in unaligned __get_user() call
        parisc: Fix printk time during boot
        parisc: Fix backtrace on PA-RISC
      5975b2c0
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security · d834502e
      Linus Torvalds authored
      Pull key handling update from James Morris:
       "This alters a new keyctl function added in the current merge window to
        allow for a future extension planned for the next merge window"
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
        KEYS: Add placeholder for KDF usage with DH
      d834502e
    • Eric W. Biederman's avatar
      devpts: Make each mount of devpts an independent filesystem. · eedf265a
      Eric W. Biederman authored
      
      
      The /dev/ptmx device node is changed to lookup the directory entry "pts"
      in the same directory as the /dev/ptmx device node was opened in.  If
      there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx
      uses that filesystem.  Otherwise the open of /dev/ptmx fails.
      
      The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that
      userspace can now safely depend on each mount of devpts creating a new
      instance of the filesystem.
      
      Each mount of devpts is now a separate and equal filesystem.
      
      Reserved ttys are now available to all instances of devpts where the
      mounter is in the initial mount namespace.
      
      A new vfs helper path_pts is introduced that finds a directory entry
      named "pts" in the directory of the passed in path, and changes the
      passed in path to point to it.  The helper path_pts uses a function
      path_parent_directory that was factored out of follow_dotdot.
      
      In the implementation of devpts:
       - devpts_mnt is killed as it is no longer meaningful if all mounts of
         devpts are equal.
       - pts_sb_from_inode is replaced by just inode->i_sb as all cached
         inodes in the tty layer are now from the devpts filesystem.
       - devpts_add_ref is rolled into the new function devpts_ptmx.  And the
         unnecessary inode hold is removed.
       - devpts_del_ref is renamed devpts_release and reduced to just a
         deacrivate_super.
       - The newinstance mount option continues to be accepted but is now
         ignored.
      
      In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as
      they are never used.
      
      Documentation/filesystems/devices.txt is updated to describe the current
      situation.
      
      This has been verified to work properly on openwrt-15.05, centos5,
      centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3,
      ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1,
      slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01.  With the
      caveat that on centos6 and on slackware-14.1 that there wind up being
      two instances of the devpts filesystem mounted on /dev/pts, the lower
      copy does not end up getting used.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Greg KH <greg@kroah.com>
      Cc: Peter Hurley <peter@hurleysoftware.com>
      Cc: Peter Anvin <hpa@zytor.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
      Cc: Willy Tarreau <w@1wt.eu>
      Cc: Aurelien Jarno <aurelien@aurel32.net>
      Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
      Cc: Jann Horn <jann@thejh.net>
      Cc: Jiri Slaby <jslaby@suse.com>
      Cc: Florian Weimer <fw@deneb.enyo.de>
      Cc: Konstantin Khlebnikov <koct9i@gmail.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      eedf265a
    • Helge Deller's avatar
      58f1c654
    • Helge Deller's avatar
      parisc: Fix pagefault crash in unaligned __get_user() call · 8b78f260
      Helge Deller authored
      
      
      One of the debian buildd servers had this crash in the syslog without
      any other information:
      
       Unaligned handler failed, ret = -2
       clock_adjtime (pid 22578): Unaligned data reference (code 28)
       CPU: 1 PID: 22578 Comm: clock_adjtime Tainted: G  E  4.5.0-2-parisc64-smp #1 Debian 4.5.4-1
       task: 000000007d9960f8 ti: 00000001bde7c000 task.ti: 00000001bde7c000
      
            YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
       PSW: 00001000000001001111100000001111 Tainted: G            E
       r00-03  000000ff0804f80f 00000001bde7c2b0 00000000402d2be8 00000001bde7c2b0
       r04-07  00000000409e1fd0 00000000fa6f7fff 00000001bde7c148 00000000fa6f7fff
       r08-11  0000000000000000 00000000ffffffff 00000000fac9bb7b 000000000002b4d4
       r12-15  000000000015241c 000000000015242c 000000000000002d 00000000fac9bb7b
       r16-19  0000000000028800 0000000000000001 0000000000000070 00000001bde7c218
       r20-23  0000000000000000 00000001bde7c210 0000000000000002 0000000000000000
       r24-27  0000000000000000 0000000000000000 00000001bde7c148 00000000409e1fd0
       r28-31  0000000000000001 00000001bde7c320 00000001bde7c350 00000001bde7c218
       sr00-03  0000000001200000 0000000001200000 0000000000000000 0000000001200000
       sr04-07  0000000000000000 0000000000000000 0000000000000000 0000000000000000
      
       IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000402d2e84 00000000402d2e88
        IIR: 0ca0d089    ISR: 0000000001200000  IOR: 00000000fa6f7fff
        CPU:        1   CR30: 00000001bde7c000 CR31: ffffffffffffffff
        ORIG_R28: 00000002369fe628
        IAOQ[0]: compat_get_timex+0x2dc/0x3c0
        IAOQ[1]: compat_get_timex+0x2e0/0x3c0
        RP(r2): compat_get_timex+0x40/0x3c0
       Backtrace:
        [<00000000402d4608>] compat_SyS_clock_adjtime+0x40/0xc0
        [<0000000040205024>] syscall_exit+0x0/0x14
      
      This means the userspace program clock_adjtime called the clock_adjtime()
      syscall and then crashed inside the compat_get_timex() function.
      Syscalls should never crash programs, but instead return EFAULT.
      
      The IIR register contains the executed instruction, which disassebles
      into "ldw 0(sr3,r5),r9".
      This load-word instruction is part of __get_user() which tried to read the word
      at %r5/IOR (0xfa6f7fff). This means the unaligned handler jumped in.  The
      unaligned handler is able to emulate all ldw instructions, but it fails if it
      fails to read the source e.g. because of page fault.
      
      The following program reproduces the problem:
      
      #define _GNU_SOURCE
      #include <unistd.h>
      #include <sys/syscall.h>
      #include <sys/mman.h>
      
      int main(void) {
              /* allocate 8k */
              char *ptr = mmap(NULL, 2*4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
              /* free second half (upper 4k) and make it invalid. */
              munmap(ptr+4096, 4096);
              /* syscall where first int is unaligned and clobbers into invalid memory region */
              /* syscall should return EFAULT */
              return syscall(__NR_clock_adjtime, 0, ptr+4095);
      }
      
      To fix this issue we simply need to check if the faulting instruction address
      is in the exception fixup table when the unaligned handler failed. If it
      is, call the fixup routine instead of crashing.
      
      While looking at the unaligned handler I found another issue as well: The
      target register should not be modified if the handler was unsuccessful.
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      Cc: stable@vger.kernel.org
      8b78f260
    • Helge Deller's avatar
      parisc: Fix printk time during boot · 0032c088
      Helge Deller authored
      
      
      Avoid showing invalid printk time stamps during boot.
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      Reviewed-by: default avatarAaro Koskinen <aaro.koskinen@iki.fi>
      0032c088
  3. 04 Jun, 2016 2 commits
    • Mikulas Patocka's avatar
      parisc: Fix backtrace on PA-RISC · be24a897
      Mikulas Patocka authored
      
      
      This patch fixes backtrace on PA-RISC
      
      There were several problems:
      
      1) The code that decodes instructions handles instructions that subtract
      from the stack pointer incorrectly. If the instruction subtracts the
      number X from the stack pointer the code increases the frame size by
      (0x100000000-X).  This results in invalid accesses to memory and
      recursive page faults.
      
      2) Because gcc reorders blocks, handling instructions that subtract from
      the frame pointer is incorrect. For example, this function
      	int f(int a)
      	{
      		if (__builtin_expect(a, 1))
      			return a;
      		g();
      		return a;
      	}
      is compiled in such a way, that the code that decreases the stack
      pointer for the first "return a" is placed before the code for "g" call.
      If we recognize this decrement, we mistakenly believe that the frame
      size for the "g" call is zero.
      
      To fix problems 1) and 2), the patch doesn't recognize instructions that
      decrease the stack pointer at all. To further safeguard the unwind code
      against nonsense values, we don't allow frame size larger than
      Total_frame_size.
      
      3) The backtrace is not locked. If stack dump races with module unload,
      invalid table can be accessed.
      
      This patch adds a spinlock when processing module tables.
      
      Note, that for correct backtrace, you need recent binutils.
      Binutils 2.18 from Debian 5 produce garbage unwind tables.
      Binutils 2.21 work better (it sometimes forgets function frames, but at
      least it doesn't generate garbage).
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      be24a897
    • Linus Torvalds's avatar
      Merge tag 'drm-fixes-for-v4.7-rc2' of git://people.freedesktop.org/~airlied/linux · 049ec1b5
      Linus Torvalds authored
      Pull drm fixes from Dave Airlie:
       "A bunch of ARM drivers got into the fixes vibe this time around, so
        this contains a bunch of fixes for imx, atmel hlcdc, arm hdlcd (only
        so many combos of hlcd), mediatek and omap drm.
      
        Other than that there is one mgag200 fix and a few core drm regression
        fixes"
      
      * tag 'drm-fixes-for-v4.7-rc2' of git://people.freedesktop.org/~airlied/linux: (34 commits)
        drm/omap: fix unused variable warning.
        drm: hdlcd: Add information about the underlying framebuffers in debugfs
        drm: hdlcd: Cleanup the atomic plane operations
        drm/hdlcd: Fix up crtc_state->event handling
        drm: hdlcd: Revamp runtime power management
        drm/mediatek: mtk_dsi: Remove spurious drm_connector_unregister
        drm/mediatek: mtk_dpi: remove invalid error message
        drm: atmel-hlcdc: fix a NULL check
        drm: atmel-hlcdc: fix atmel_hlcdc_crtc_reset() implementation
        drm/mgag200: Black screen fix for G200e rev 4
        drm: Wrap direct calls to driver->gem_free_object from CMA
        drm: fix fb refcount issue with atomic modesetting
        drm: make drm_atomic_set_mode_prop_for_crtc() more reliable
        drm/sti: remove extra mode fixup
        drm: add missing drm_mode_set_crtcinfo call
        drm/omap: include gpio/consumer.h where needed
        drm/omap: include linux/seq_file.h where needed
        Revert "drm/omap: no need to select OMAP2_DSS"
        drm/omap: Remove regulator API abuse
        OMAPDSS: HDMI5: Change DDC timings
        ...
      049ec1b5