1e46ef1762
__tcf_ipt_init() can fail after the idr has been successfully reserved.
When this happens, subsequent attempts to configure xt/ipt rules using
the same idr value systematically fail with -ENOSPC:
# tc action add action xt -j LOG --log-prefix test1 index 100
tablename: mangle hook: NF_IP_POST_ROUTING
target: LOG level warning prefix "test1" index 100
RTNETLINK answers: Cannot allocate memory
We have an error talking to the kernel
Command "(null)" is unknown, try "tc actions help".
# tc action add action xt -j LOG --log-prefix test1 index 100
tablename: mangle hook: NF_IP_POST_ROUTING
target: LOG level warning prefix "test1" index 100
RTNETLINK answers: No space left on device
We have an error talking to the kernel
Command "(null)" is unknown, try "tc actions help".
# tc action add action xt -j LOG --log-prefix test1 index 100
tablename: mangle hook: NF_IP_POST_ROUTING
target: LOG level warning prefix "test1" index 100
RTNETLINK answers: No space left on device
We have an error talking to the kernel
...
Fix this in the error path of __tcf_ipt_init(), calling tcf_idr_release()
in place of tcf_idr_cleanup(). Since tcf_ipt_release() can now be called
when tcfi_t is NULL, we also need to protect calls to ipt_destroy_target()
to avoid NULL pointer dereference.
Fixes: 65a206c01e8e ("net/sched: Change act_api and act_xxx modules to use IDR")
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.