1. 26 Aug, 2017 2 commits
    • Ian Abbott's avatar
      staging: comedi: jr3_pci: fix possible null pointer dereference · e86ba264
      Ian Abbott authored
      commit 45292be0 upstream.
      
      For some reason, the driver does not consider allocation of the
      subdevice private data to be a fatal error when attaching the COMEDI
      device.  It tests the subdevice private data pointer for validity at
      certain points, but omits some crucial tests.  In particular,
      `jr3_pci_auto_attach()` calls `jr3_pci_alloc_spriv()` to allocate and
      initialize the subdevice private data, but the same function
      subsequently dereferences the pointer to access the `next_time_min` and
      `next_time_max` members without checking it first.  The other missing
      test is in the timer expiry routine `jr3_pci_poll_dev()`, but it will
      crash before it gets that far.
      
      Fix the bug by returning `-ENOMEM` from `jr3_pci_auto_attach()` as soon
      as one of the calls to `jr3_pci_alloc_spriv()` returns `NULL`.  The
      COMEDI core will subsequently call `jr3_pci_detach()` to clean up.
      Signed-off-by: default avatarIan Abbott <abbotti@mev.co.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      e86ba264
    • Arnd Bergmann's avatar
      pvrusb2: reduce stack usage pvr2_eeprom_analyze() · a6334ec1
      Arnd Bergmann authored
      commit 6830733d upstream.
      
      The driver uses a relatively large data structure on the stack, which
      showed up on my radar as we get a warning with the "latent entropy"
      GCC plugin:
      
      drivers/media/usb/pvrusb2/pvrusb2-eeprom.c:153:1: error: the frame size of 1376 bytes is larger than 1152 bytes [-Werror=frame-larger-than=]
      
      The warning is usually hidden as we raise the warning limit to 2048
      when the plugin is enabled, but I'd like to lower that again in the
      future, and making this function smaller helps to do that without
      build regressions.
      
      Further analysis shows that putting an 'i2c_client' structure on
      the stack is not really supported, as the embedded 'struct device'
      is not initialized here, and we are only saved by the fact that
      the function that is called here does not use the pointer at all.
      
      Fixes: d855497e ("V4L/DVB (4228a): pvrusb2 to kernel 2.6.18")
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
      Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      a6334ec1
  2. 18 Jul, 2017 38 commits