tipc: fix infinite loop in __tipc_nl_compat_dumpit

cmd->dumpit callback can return a negative errno, causing an infinite
loop due to the while(len) condition. As the loop never terminates,
genl_mutex is never released, and other tasks waiting on it starve in D
state.

Check dumpit's return value, propagate it and jump to err_out on error.

Reported-by: syzbot+85d0bec020d805014a3a@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=85d0bec020d805014a3a
Fixes: d0796d1ef6 ("tipc: convert legacy nl bearer dump to nl compat")
Signed-off-by: Helen Koike <koike@igalia.com>
Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech
Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech>
Link: https://patch.msgid.link/20260713204940.647668-1-koike@igalia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Helen Koike 2026-07-13 17:49:35 -03:00 committed by Jakub Kicinski
parent 6347c5314c
commit 22f8aa3596

View File

@ -221,6 +221,10 @@ static int __tipc_nl_compat_dumpit(struct tipc_nl_compat_cmd_dump *cmd,
int rem;
len = (*cmd->dumpit)(buf, &cb);
if (len < 0) {
err = len;
goto err_out;
}
nlmsg_for_each_msg(nlmsg, nlmsg_hdr(buf), len, rem) {
err = nlmsg_parse_deprecated(nlmsg, GENL_HDRLEN,