Hi,
Static analysis on linux-next has picked up a potential bug with commit:
commit 7b0db85737db3f4d76b2a412e4f19eae59b8b494
Author: Yuval Mintz <yuv...@mellanox.com>
Date: Wed Feb 28 23:29:39 2018 +0200
ipmr, ip6mr: Unite dumproute flows
in function mr_table_dump(), s_e is and never seems to change, so the
check if (e < s_e) is never true: See code below, as annotated by
CoverityScan:
317 }
assignment: Assigning: e = 0U.
318 e = 0;
assignment: Assigning: s_e = 0U.
319 s_e = 0;
320
321 spin_lock_bh(lock);
322 list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) {
at_least: At condition e < s_e, the value of e must be at least 0.
const: At condition e < s_e, the value of s_e must be equal to 0.
dead_error_condition: The condition e < s_e cannot be true.
323 if (e < s_e)
CID 1474511 (#1 of 1): Logically dead code (DEADCODE)
dead_error_line: Execution cannot reach this statement: goto next_entry2;.
324 goto next_entry2;
325 if (filter->dev &&
326 !mr_mfc_uses_dev(mrt, mfc, filter->dev))
327 goto next_entry2;
328
329 err = fill(mrt, skb, NETLINK_CB(cb->skb).portid,
330 cb->nlh->nlmsg_seq, mfc, RTM_NEWROUTE, flags);
331 if (err < 0) {
332 spin_unlock_bh(lock);
333 goto out;
334 }
335next_entry2:
incr: Incrementing e. The value of e is now 1.
incr: Incrementing e. The value of e is now 2.
336 e++;
Note that the zero'ing of e and s_e for ipmr and ip6mr was added in by
earlier commits:
commit 8fb472c09b9df478a062eacc7841448e40fc3c17
Author: Nikolay Aleksandrov <niko...@cumulusnetworks.com>
Date: Thu Jan 12 15:53:33 2017 +0100
ipmr: improve hash scalability
commit 87c418bf1323d57140f4b448715f64de3fbb7e91
Author: Yuval Mintz <yuv...@mellanox.com>
Date: Wed Feb 28 23:29:31 2018 +0200
ip6mr: Align hash implementation to ipmr
Anyhow, this looks incorrect, but I'm not familiar with this code to
suggest the correct fix.
Colin
