[ Upstream commit 6c015a2256801597fadcbc11d287774c9c512fa5 ]
__dev_alloc_name(), when supplied with a name containing '%d',
will search for the first available device number to generate a
unique device name.
Since commit ff92741270 ("net:
introduce name_node struct to be used in hashlist") network
devices may have alternate names. __dev_alloc_name() does take
these alternate names into account, possibly generating a name
that is already taken and failing with -ENFILE as a result.
This demonstrates the bug:
# rmmod dummy 2>/dev/null
# ip link property add dev lo altname dummy0
# modprobe dummy numdummies=1
modprobe: ERROR: could not insert 'dummy': Too many open files in system
Instead of creating a device named dummy1, modprobe fails.
Fix this by checking all the names in the d->name_node list, not just d->name.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Fixes: ff92741270 ("net: introduce name_node struct to be used in hashlist")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
943e1583bf