On (07/09/17 11:49), Linus Torvalds wrote: > > On Sat, Jul 8, 2017 at 3:36 AM, David Miller <da...@davemloft.net> wrote: > > > > 8) Fix socket leak on accept() in RDS, from Sowmini Varadhan. Also > > add a WARN_ON() to sock_graft() so other protocol stacks don't trip > > over this as well. > > Hmm. This one triggers for me on both my desktop and laptop at bootup. > Bog-standard machines, running F25 and F24 respectively. > > The warning doesn't seem particularly useful, although maybe that > "alg_accept()" gives people who know this code enough of a clue.
My initial question was whether sock_graft() should do a sock_put() before cutting loose the existing parent->sk and assigning a new parent->sk (https://www.spinics.net/lists/netdev/msg442191.html) It look like PF_ALG sets up a ->sk in alg_create() (but this would get over-written in alg_accept()?) Cc'ing Herbert to see if this is expected behavior (and PF_ALG somehow does the right thing with the refcount for the ->sk set up in alg_create) in which case I suppose we should drop the WARN_ON. --Sowmini > ------------[ cut here ]------------ > WARNING: CPU: 1 PID: 492 at ./include/net/sock.h:1700 > af_alg_accept+0x1bf/0x1f0 > CPU: 1 PID: 492 Comm: systemd-cryptse Not tainted 4.12.0-09010-g2b976203417c > #1 > Hardware name: System manufacturer System Product Name/Z170-K, BIOS > 1803 05/06/2016 > RIP: 0010:af_alg_accept+0x1bf/0x1f0 > Call Trace: > alg_accept+0x15/0x20 > SYSC_accept4+0x105/0x210 > ? getnstimeofday64+0xe/0x20 > ? __audit_syscall_entry+0xb1/0xf0 > ? syscall_trace_enter+0x1bd/0x2d0 > ? __audit_syscall_exit+0x1a5/0x2a0 > SyS_accept+0x10/0x20 > do_syscall_64+0x61/0x140 > entry_SYSCALL64_slow_path+0x25/0x25 > ---[ end trace a35e5baea85df269 ]---
