From: Amit Cohen amcohen@nvidia.com
stable inclusion from stable-v4.19.320 commit e061713d466b9be56b66dd6fb50538ad2c5564ac category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IACSAA CVE: CVE-2024-39501
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
--------------------------------
[ Upstream commit f67a90a0c8f5b3d0acc18f10650d90fec44775f9 ]
Lately, an additional locking was added by commit c0a40097f0bc ("drivers: core: synchronize really_probe() and dev_uevent()"). The locking protects dev_uevent() calling. This function is used to send messages from the kernel to user space. Uevent messages notify user space about changes in device states, such as when a device is added, removed, or changed. These messages are used by udev (or other similar user-space tools) to apply device-specific rules.
After reloading devlink instance, udev events should be processed. This locking causes a short delay of udev events handling.
One example for useful udev rule is renaming ports. 'forwading.config' can be configured to use names after udev rules are applied. Some tests run devlink_reload() and immediately use the updated names. This worked before the above mentioned commit was pushed, but now the delay of uevent messages causes that devlink_reload() returns before udev events are handled and tests fail.
Adjust devlink_reload() to not assume that udev events are already processed when devlink reload is done, instead, wait for udev events to ensure they are processed before returning from the function.
Without this patch: TESTS='rif_mac_profile' ./resource_scale.sh TEST: 'rif_mac_profile' 4 [ OK ] sysctl: cannot stat /proc/sys/net/ipv6/conf/swp1/disable_ipv6: No such file or directory sysctl: cannot stat /proc/sys/net/ipv6/conf/swp1/disable_ipv6: No such file or directory sysctl: cannot stat /proc/sys/net/ipv6/conf/swp2/disable_ipv6: No such file or directory sysctl: cannot stat /proc/sys/net/ipv6/conf/swp2/disable_ipv6: No such file or directory Cannot find device "swp1" Cannot find device "swp2" TEST: setup_wait_dev (: Interface swp1 does not come up.) [FAIL]
With this patch: $ TESTS='rif_mac_profile' ./resource_scale.sh TEST: 'rif_mac_profile' 4 [ OK ] TEST: 'rif_mac_profile' overflow 5 [ OK ]
This is relevant not only for this test.
Fixes: bc7cbb1e9f4c ("selftests: forwarding: Add devlink_lib.sh") Signed-off-by: Amit Cohen amcohen@nvidia.com Reviewed-by: Ido Schimmel idosch@nvidia.com Signed-off-by: Petr Machata petrm@nvidia.com Link: https://patch.msgid.link/89367666e04b38a8993027f1526801ca327ab96a.1720709333... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Chen Jun chenjun102@huawei.com --- tools/testing/selftests/net/forwarding/devlink_lib.sh | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/tools/testing/selftests/net/forwarding/devlink_lib.sh b/tools/testing/selftests/net/forwarding/devlink_lib.sh index 5ab1e5f43022..ea708b6c1e00 100644 --- a/tools/testing/selftests/net/forwarding/devlink_lib.sh +++ b/tools/testing/selftests/net/forwarding/devlink_lib.sh @@ -105,4 +105,6 @@ devlink_reload() still_pending=$(devlink resource show "$DEVLINK_DEV" | \ grep -c "size_new") check_err $still_pending "Failed reload - There are still unset sizes" + + udevadm settle }