RDMA/IPoIB: Fix format truncation compilation errors

[ Upstream commit 49ca2b2ef3d003402584c68ae7b3055ba72e750a ]

Truncate the device name to store IPoIB VLAN name.

[leonro@5b4e8fba4ddd kernel]$ make -s -j 20 allmodconfig
[leonro@5b4e8fba4ddd kernel]$ make -s -j 20 W=1 drivers/infiniband/ulp/ipoib/
drivers/infiniband/ulp/ipoib/ipoib_vlan.c: In function ‘ipoib_vlan_add’:
drivers/infiniband/ulp/ipoib/ipoib_vlan.c:187:52: error: ‘%04x’
directive output may be truncated writing 4 bytes into a region of size
between 0 and 15 [-Werror=format-truncation=]
  187 |         snprintf(intf_name, sizeof(intf_name), "%s.%04x",
      |                                                    ^~~~
drivers/infiniband/ulp/ipoib/ipoib_vlan.c:187:48: note: directive
argument in the range [0, 65535]
  187 |         snprintf(intf_name, sizeof(intf_name), "%s.%04x",
      |                                                ^~~~~~~~~
drivers/infiniband/ulp/ipoib/ipoib_vlan.c:187:9: note: ‘snprintf’ output
between 6 and 21 bytes into a destination of size 16
  187 |         snprintf(intf_name, sizeof(intf_name), "%s.%04x",
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  188 |                  ppriv->dev->name, pkey);
      |                  ~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[6]: *** [scripts/Makefile.build:244: drivers/infiniband/ulp/ipoib/ipoib_vlan.o] Error 1
make[6]: *** Waiting for unfinished jobs....

Fixes: 9baa0b036410 ("IB/ipoib: Add rtnl_link_ops support")
Link: https://lore.kernel.org/r/e9d3e1fef69df4c9beaf402cc3ac342bad680791.1715240029.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit b469345f1fca84bed4dea3cae85faa401cf9bf3e)
[Vegard: fix conflict in context due to missing commit
 577e07ffbad9960551a6821b74af90a216ac10e2 ("IB/ipoib: Get rid of
 IPOIB_FLAG_GOING_DOWN").]
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
1 file changed