WARNING: refcount bug in p9_req_put
Status: fixed on 2020/11/16 12:12
Fix commit: a39c46067c84 net/9p: validate fds in p9_fd_open
First crash: 1283d, last: 728d

Cause bisection: the cause commit could be any of (bisect log):
  cbce4f444798 net/mlx5e: Enable adaptive-TX moderation
  623ad755226c net/dim: Support adaptive TX moderation
  8399743a5a67 Merge branch 'net-DIM-tx'
  026a807c2de3 net/dim: Rename *_get_profile() functions to *_get_rx_moderation()
  a06ac0d67d9f Revert "net: init sk_cookie for inet socket"
  8c2320e84c19 tcp: md5: only call tp->af_specific->md5_lookup() for md5 sockets
  db688c24eada vhost_net: use packet weight for rx handler, too
  0c6f69a5e364 rhashtable: remove outdated comments about grow_decision etc
  9c20b9372fba net: fib_rules: fix l3mdev netlink attr processing
  82266e98dd4d rhashtable: Revise incorrect comment on r{hl, hash}table_walk_enter()
  b300fcf883ac selftests: net: update .gitignore with missing test
  064223c1231c dca: make function dca_common_get_tag static
  b41cc04b662a rhashtable: reset iter when rhashtable_walk_start sees new table
  5d240a8936f6 rhashtable: improve rhashtable_walk stability when stop/start used.
  f7c3b12cec09 Merge branch 'ipv6-couple-of-fixes-for-rcu-change-to-from'
  5cb5ce336338 Merge branch 'rhash-cleanups'
  8a14e46f1402 net/ipv6: Fix missing rcu dereferences on from
  660de409e25b ipconfig: Document setting of NIS domain name
  c3c14da0288d net/ipv6: add rcu locking to ip6_negative_advice
  40cde8249a82 Merge branch 'qed-debug-data'
  e18bdc83aec4 ipconfig: Tidy up reporting of name servers
  1ac4329a1cff qed: Add configuration information to register dump and debug data
  4e1a8af28d56 ipconfig: BOOTP: Don't request IEN-116 name servers
  b60bfdfec5b8 qed: Delete unused parameter p_ptt from mcp APIs
  de1fa15b6642 ipconfig: BOOTP: Request CONF_NAMESERVERS_MAX name servers
  5f0456b43140 net: stmmac: Implement logic to automatically select HW Interface
  8b0b37c5644e ipconfig: Document /proc/net/pnp
  22148df0d0bd r8169: don't use netif_info et al before net_device has been registered
  300eec7c0a24 ipconfig: Correctly initialise ic_nameservers
  4d019b3f80dc ipconfig: Create /proc/net/ipconfig directory
  c6849a3ac17e net: init sk_cookie for inet socket
  c04d2cb2009f ipconfig: Write NTP server IPs to /proc/net/ipconfig/ntp_servers
  ec8c360a6ecd Merge branch 'fib-rules-extack-support'
  b16fb418b1bf net: fib_rules: add extack support
  bc0fbc66ad1b Merge branch 'ipconfig-NTP-server-support-bug-fixes-documentation-improvements'
  c7d852e301d8 qed: Fix copying 2 strings
  f9d4b0c1e969 fib_rules: move common handling of newrule delrule msgs into fib_nl2rule
  080aaddae5b3 fsl/fman_port: remove redundant check on port->rev_info.major
  a56e6bcd34b5 tc-testing: updated ife test cases
  6163849d289b net: introduce a new tracepoint for tcp_rcv_space_adjust
  95ad7544ad3f net/tls: remove redundant second null check on sgout
  091311debcf0 net/ipv6: fix LOCKDEP issue in rt6_remove_exception_rt()
  48d7a07ba355 hv_netvsc: select needed ucs2_string routine
  16f4faa4f06f liquidio: Swap VF representor Tx and Rx statistics
  e0ada51db907 Merge git://
  c749fa181bd5 Merge git://

Fix bisection: fixed by (bisect log) :
commit a39c46067c845a8a2d7144836e9468b7f072343e
Author: Christoph Hellwig <>
Date: Fri Jul 10 08:57:22 2020 +0000

  net/9p: validate fds in p9_fd_open

similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 WARNING: refcount bug in p9_req_put 2 931d 972d 0/1 auto-closed as invalid on 2020/02/28 21:29

Sample crash report:

Crashes (6):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-root 2019/05/02 02:37 upstream 459e3a21535a 7516d9fa .config log report syz
ci-upstream-kasan-gce-root 2019/07/02 00:50 upstream 6fbc7275c7a9 cccc4302 .config log report
ci-upstream-kasan-gce-root 2019/06/21 02:17 upstream abf02e2964b3 34bf9440 .config log report
ci-upstream-kasan-gce-root 2019/05/02 01:47 upstream 459e3a21535a 7516d9fa .config log report
ci-upstream-kasan-gce-selinux-root 2018/11/14 00:53 upstream ccda4af0f4b9 5f5f6d14 .config log report
ci-upstream-linux-next-kasan-gce-root 2019/03/09 03:36 linux-next cf08baa29613 12365b99 .config log report