ipv6: fix error handling in disable_ipv6 sysctl

When writing to the disable_ipv6 sysctl, if proc_dointvec() fails to
parse the input, it returns a negative error code. The current
implementation is overwriting that error for write operations.

This results in a silent failure, it returns a successful write although
the configuration was not modified at all. When modifying the "all"
variant it can also modify the configuration of existing interfaces to
the wrong value.

Fix this by checking the return value of proc_dointvec() and returning
early on failure.

Fixes: 56d417b12e57 ("IPv6: Add 'autoconf' and 'disable_ipv6' module parameters")
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260622130857.5115-2-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions