1. 27 Feb, 2020 13 commits
    • Christian Brauner's avatar
      net-sysfs: add netdev_change_owner() · e6dee9f3
      Christian Brauner authored
      Add a function to change the owner of a network device when it is moved
      between network namespaces.
      
      Currently, when moving network devices between network namespaces the
      ownership of the corresponding sysfs entries is not changed. This leads
      to problems when tools try to operate on the corresponding sysfs files.
      This leads to a bug whereby a network device that is created in a
      network namespaces owned by a user namespace will have its corresponding
      sysfs entry owned by the root user of the corresponding user namespace.
      If such a network device has to be moved back to the host network
      namespace the permissions will still be set to the user namespaces. This
      means unprivileged users can e.g. trigger uevents for such incorrectly
      owned devices. They can also modify the settings of the device itself.
      Both of these things are unwanted.
      
      For example, workloads will create network devices in the host network
      namespace. Other tools will then proceed to move such devices between
      network namespaces owner by other user namespaces. While the ownership
      of the device itself is updated in
      net/core/net-sysfs.c:dev_change_net_namespace() the corresponding sysfs
      entry for the device is not:
      
      drwxr-xr-x 5 nobody nobody    0 Jan 25 18:08 .
      drwxr-xr-x 9 nobody nobody    0 Jan 25 18:08 ..
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 addr_assign_type
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 addr_len
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 address
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 broadcast
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier_changes
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier_down_count
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier_up_count
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 dev_id
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 dev_port
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 dormant
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 duplex
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 flags
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 gro_flush_timeout
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 ifalias
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 ifindex
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 iflink
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 link_mode
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 mtu
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 name_assign_type
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 netdev_group
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 operstate
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 phys_port_id
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 phys_port_name
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 phys_switch_id
      drwxr-xr-x 2 nobody nobody    0 Jan 25 18:09 power
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 proto_down
      drwxr-xr-x 4 nobody nobody    0 Jan 25 18:09 queues
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 speed
      drwxr-xr-x 2 nobody nobody    0 Jan 25 18:09 statistics
      lrwxrwxrwx 1 nobody nobody    0 Jan 25 18:08 subsystem -> ../../../../class/net
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 tx_queue_len
      -r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 type
      -rw-r--r-- 1 nobody nobody 4096 Jan 25 18:08 uevent
      
      However, if a device is created directly in the network namespace then
      the device's sysfs permissions will be correctly updated:
      
      drwxr-xr-x 5 root   root      0 Jan 25 18:12 .
      drwxr-xr-x 9 nobody nobody    0 Jan 25 18:08 ..
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 addr_assign_type
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 addr_len
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 address
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 broadcast
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 carrier
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 carrier_changes
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 carrier_down_count
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 carrier_up_count
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 dev_id
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 dev_port
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 dormant
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 duplex
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 flags
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 gro_flush_timeout
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 ifalias
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 ifindex
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 iflink
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 link_mode
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 mtu
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 name_assign_type
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 netdev_group
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 operstate
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 phys_port_id
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 phys_port_name
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 phys_switch_id
      drwxr-xr-x 2 root   root      0 Jan 25 18:12 power
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 proto_down
      drwxr-xr-x 4 root   root      0 Jan 25 18:12 queues
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 speed
      drwxr-xr-x 2 root   root      0 Jan 25 18:12 statistics
      lrwxrwxrwx 1 nobody nobody    0 Jan 25 18:12 subsystem -> ../../../../class/net
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 tx_queue_len
      -r--r--r-- 1 root   root   4096 Jan 25 18:12 type
      -rw-r--r-- 1 root   root   4096 Jan 25 18:12 uevent
      
      Now, when creating a network device in a network namespace owned by a
      user namespace and moving it to the host the permissions will be set to
      the id that the user namespace root user has been mapped to on the host
      leading to all sorts of permission issues:
      
      458752
      drwxr-xr-x 5 458752 458752      0 Jan 25 18:12 .
      drwxr-xr-x 9 root   root        0 Jan 25 18:08 ..
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 addr_assign_type
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 addr_len
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 address
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 broadcast
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier_changes
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier_down_count
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier_up_count
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 dev_id
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 dev_port
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 dormant
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 duplex
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 flags
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 gro_flush_timeout
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 ifalias
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 ifindex
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 iflink
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 link_mode
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 mtu
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 name_assign_type
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 netdev_group
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 operstate
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 phys_port_id
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 phys_port_name
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 phys_switch_id
      drwxr-xr-x 2 458752 458752      0 Jan 25 18:12 power
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 proto_down
      drwxr-xr-x 4 458752 458752      0 Jan 25 18:12 queues
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 speed
      drwxr-xr-x 2 458752 458752      0 Jan 25 18:12 statistics
      lrwxrwxrwx 1 root   root        0 Jan 25 18:12 subsystem -> ../../../../class/net
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 tx_queue_len
      -r--r--r-- 1 458752 458752   4096 Jan 25 18:12 type
      -rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 uevent
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e6dee9f3
    • Christian Brauner's avatar
      drivers/base/power: add dpm_sysfs_change_owner() · 3b52fc5d
      Christian Brauner authored
      Add a helper to change the owner of a device's power entries. This
      needs to happen when the ownership of a device is changed, e.g. when
      moving network devices between network namespaces.
      This function will be used to correctly account for ownership changes,
      e.g. when moving network devices between network namespaces.
      Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Reviewed-by: default avatar"Rafael J. Wysocki" <rafael@kernel.org>
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3b52fc5d
    • Christian Brauner's avatar
      device: add device_change_owner() · b8f33e5d
      Christian Brauner authored
      Add a helper to change the owner of a device's sysfs entries. This
      needs to happen when the ownership of a device is changed, e.g. when
      moving network devices between network namespaces.
      This function will be used to correctly account for ownership changes,
      e.g. when moving network devices between network namespaces.
      Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b8f33e5d
    • Christian Brauner's avatar
      sysfs: add sysfs_change_owner() · 2c4f9401
      Christian Brauner authored
      Add a helper to change the owner of sysfs objects.
      This function will be used to correctly account for kobject ownership
      changes, e.g. when moving network devices between network namespaces.
      
      This mirrors how a kobject is added through driver core which in its guts is
      done via kobject_add_internal() which in summary creates the main directory via
      create_dir(), populates that directory with the groups associated with the
      ktype of the kobject (if any) and populates the directory with the basic
      attributes associated with the ktype of the kobject (if any). These are the
      basic steps that are associated with adding a kobject in sysfs.
      Any additional properties are added by the specific subsystem itself (not by
      driver core) after it has registered the device. So for the example of network
      devices, a network device will e.g. register a queue subdirectory under the
      basic sysfs directory for the network device and than further subdirectories
      within that queues subdirectory.  But that is all specific to network devices
      and they call the corresponding sysfs functions to do that directly when they
      create those queue objects. So anything that a subsystem adds outside of what
      driver core does must also be changed by it (That's already true for removal of
      files it created outside of driver core.) and it's the same for ownership
      changes.
      Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2c4f9401
    • Christian Brauner's avatar
      sysfs: add sysfs_group{s}_change_owner() · 303a4276
      Christian Brauner authored
      Add helpers to change the owner of sysfs groups.
      This function will be used to correctly account for kobject ownership
      changes, e.g. when moving network devices between network namespaces.
      Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      303a4276
    • Christian Brauner's avatar
      sysfs: add sysfs_link_change_owner() · 0666a3ae
      Christian Brauner authored
      Add a helper to change the owner of a sysfs link.
      This function will be used to correctly account for kobject ownership
      changes, e.g. when moving network devices between network namespaces.
      Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0666a3ae
    • Christian Brauner's avatar
      sysfs: add sysfs_file_change_owner() · f70ce185
      Christian Brauner authored
      Add helpers to change the owner of a sysfs files.
      This function will be used to correctly account for kobject ownership
      changes, e.g. when moving network devices between network namespaces.
      Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f70ce185
    • Gustavo A. R. Silva's avatar
      net: cisco: Replace zero-length array with flexible-array member · d1c73cbd
      Gustavo A. R. Silva authored
      The current codebase makes use of the zero-length array language
      extension to the C90 standard, but the preferred mechanism to declare
      variable-length types such as these ones is a flexible array member[1][2],
      introduced in C99:
      
      struct foo {
              int stuff;
              struct boo array[];
      };
      
      By making use of the mechanism above, we will get a compiler warning
      in case the flexible array does not occur last in the structure, which
      will help us prevent some kind of undefined behavior bugs from being
      inadvertently introduced[3] to the codebase from now on.
      
      Also, notice that, dynamic memory allocations won't be affected by
      this change:
      
      "Flexible array members have incomplete type, and so the sizeof operator
      may not be applied. As a quirk of the original implementation of
      zero-length arrays, sizeof evaluates to zero."[1]
      
      Lastly, fix the following checkpatch warning:
      CHECK: Prefer kernel type 'u32' over 'u_int32_t'
      #61: FILE: drivers/net/ethernet/cisco/enic/vnic_devcmd.h:653:
      +	u_int32_t val[];
      
      This issue was found with the help of Coccinelle.
      
      [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
      [2] https://github.com/KSPP/linux/issues/21
      [3] commit 76497732 ("cxgb3/l2t: Fix undefined behaviour")
      Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d1c73cbd
    • Gustavo A. R. Silva's avatar
      net: marvell: Replace zero-length array with flexible-array member · 274ac283
      Gustavo A. R. Silva authored
      The current codebase makes use of the zero-length array language
      extension to the C90 standard, but the preferred mechanism to declare
      variable-length types such as these ones is a flexible array member[1][2],
      introduced in C99:
      
      struct foo {
              int stuff;
              struct boo array[];
      };
      
      By making use of the mechanism above, we will get a compiler warning
      in case the flexible array does not occur last in the structure, which
      will help us prevent some kind of undefined behavior bugs from being
      inadvertently introduced[3] to the codebase from now on.
      
      Also, notice that, dynamic memory allocations won't be affected by
      this change:
      
      "Flexible array members have incomplete type, and so the sizeof operator
      may not be applied. As a quirk of the original implementation of
      zero-length arrays, sizeof evaluates to zero."[1]
      
      This issue was found with the help of Coccinelle.
      
      [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
      [2] https://github.com/KSPP/linux/issues/21
      [3] commit 76497732 ("cxgb3/l2t: Fix undefined behaviour")
      Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      274ac283
    • Gustavo A. R. Silva's avatar
      net: hns: Replace zero-length array with flexible-array member · c5d6cf90
      Gustavo A. R. Silva authored
      The current codebase makes use of the zero-length array language
      extension to the C90 standard, but the preferred mechanism to declare
      variable-length types such as these ones is a flexible array member[1][2],
      introduced in C99:
      
      struct foo {
              int stuff;
              struct boo array[];
      };
      
      By making use of the mechanism above, we will get a compiler warning
      in case the flexible array does not occur last in the structure, which
      will help us prevent some kind of undefined behavior bugs from being
      inadvertently introduced[3] to the codebase from now on.
      
      Also, notice that, dynamic memory allocations won't be affected by
      this change:
      
      "Flexible array members have incomplete type, and so the sizeof operator
      may not be applied. As a quirk of the original implementation of
      zero-length arrays, sizeof evaluates to zero."[1]
      
      This issue was found with the help of Coccinelle.
      
      [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
      [2] https://github.com/KSPP/linux/issues/21
      [3] commit 76497732 ("cxgb3/l2t: Fix undefined behaviour")
      Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c5d6cf90
    • Gustavo A. R. Silva's avatar
      sfc: Replace zero-length array with flexible-array member · 62f19142
      Gustavo A. R. Silva authored
      The current codebase makes use of the zero-length array language
      extension to the C90 standard, but the preferred mechanism to declare
      variable-length types such as these ones is a flexible array member[1][2],
      introduced in C99:
      
      struct foo {
              int stuff;
              struct boo array[];
      };
      
      By making use of the mechanism above, we will get a compiler warning
      in case the flexible array does not occur last in the structure, which
      will help us prevent some kind of undefined behavior bugs from being
      inadvertently introduced[3] to the codebase from now on.
      
      Also, notice that, dynamic memory allocations won't be affected by
      this change:
      
      "Flexible array members have incomplete type, and so the sizeof operator
      may not be applied. As a quirk of the original implementation of
      zero-length arrays, sizeof evaluates to zero."[1]
      
      This issue was found with the help of Coccinelle.
      
      [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
      [2] https://github.com/KSPP/linux/issues/21
      [3] commit 76497732 ("cxgb3/l2t: Fix undefined behaviour")
      Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Acked-by: default avatarMartin Habets <mhabets@solarflare.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      62f19142
    • Gustavo A. R. Silva's avatar
      qlogic: Replace zero-length array with flexible-array member · 4a34d825
      Gustavo A. R. Silva authored
      The current codebase makes use of the zero-length array language
      extension to the C90 standard, but the preferred mechanism to declare
      variable-length types such as these ones is a flexible array member[1][2],
      introduced in C99:
      
      struct foo {
              int stuff;
              struct boo array[];
      };
      
      By making use of the mechanism above, we will get a compiler warning
      in case the flexible array does not occur last in the structure, which
      will help us prevent some kind of undefined behavior bugs from being
      inadvertently introduced[3] to the codebase from now on.
      
      Also, notice that, dynamic memory allocations won't be affected by
      this change:
      
      "Flexible array members have incomplete type, and so the sizeof operator
      may not be applied. As a quirk of the original implementation of
      zero-length arrays, sizeof evaluates to zero."[1]
      
      This issue was detected with the help of Coccinelle.
      
      [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
      [2] https://github.com/KSPP/linux/issues/21
      [3] commit 76497732 ("cxgb3/l2t: Fix undefined behaviour")
      Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4a34d825
    • Florian Fainelli's avatar
      Revert "net: dsa: bcm_sf2: Also configure Port 5 for 2Gb/sec on 7278" · 3f02735e
      Florian Fainelli authored
      This reverts commit 7458bd54 ("net: dsa:
      bcm_sf2: Also configure Port 5 for 2Gb/sec on 7278") as it causes
      advanced congestion buffering issues with 7278 switch devices when using
      their internal Giabit PHY. While this is being debugged, continue with
      conservative defaults that work and do not cause packet loss.
      
      Fixes: 7458bd54 ("net: dsa: bcm_sf2: Also configure Port 5 for 2Gb/sec on 7278")
      Signed-off-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
      Reviewed-by: default avatarVivien Didelot <vivien.didelot@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3f02735e
  2. 26 Feb, 2020 1 commit
  3. 25 Feb, 2020 11 commits
  4. 24 Feb, 2020 15 commits