On Tue, Feb 13, 2018 at 12:15 PM, Dmitry Vyukov <dvyu...@google.com> wrote: > > On Thu, Jan 4, 2018 at 8:36 PM, Tom Herbert <t...@quantonium.net> wrote: > > On Thu, Jan 4, 2018 at 4:10 AM, syzbot > > <syzbot+3c6c745b0d2f341bb...@syzkaller.appspotmail.com> wrote: > >> Hello, > >> > >> syzkaller hit the following crash on > >> 6bb8824732f69de0f233ae6b1a8158e149627b38 > >> git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/master > >> compiler: gcc (GCC) 7.1.1 20170620 > >> .config is attached > >> Raw console output is attached. > >> Unfortunately, I don't have any reproducer for this bug yet. > >> > >> > >> IMPORTANT: if you fix the bug, please add the following tag to the commit: > >> Reported-by: syzbot+3c6c745b0d2f341bb...@syzkaller.appspotmail.com > >> It will help syzbot understand when the bug is fixed. See footer for > >> details. > >> If you forward the report, please keep this part and the footer. > >> > >> Use struct sctp_assoc_value instead > >> sctp: [Deprecated]: syz-executor4 (pid 12483) Use of int in maxseg socket > >> option. > >> Use struct sctp_assoc_value instead > >> ------------[ cut here ]------------ > >> ODEBUG: free active (active state 0) object type: work_struct hint: > >> strp_work+0x0/0xf0 net/strparser/strparser.c:381 > >> WARNING: CPU: 1 PID: 3502 at lib/debugobjects.c:291 > >> debug_print_object+0x166/0x220 lib/debugobjects.c:288 > >> Kernel panic - not syncing: panic_on_warn set ... > >> > >> CPU: 1 PID: 3502 Comm: kworker/u4:4 Not tainted 4.15.0-rc5+ #170 > >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > >> Google 01/01/2011 > >> Workqueue: kkcmd kcm_tx_work > >> Call Trace: > >> __dump_stack lib/dump_stack.c:17 [inline] > >> dump_stack+0x194/0x257 lib/dump_stack.c:53 > >> panic+0x1e4/0x41c kernel/panic.c:183 > >> __warn+0x1dc/0x200 kernel/panic.c:547 > >> report_bug+0x211/0x2d0 lib/bug.c:184 > >> fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178 > >> fixup_bug arch/x86/kernel/traps.c:247 [inline] > >> do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296 > >> do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 > >> invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1061 > >> RIP: 0010:debug_print_object+0x166/0x220 lib/debugobjects.c:288 > >> RSP: 0018:ffff8801c0ee7068 EFLAGS: 00010086 > >> RAX: dffffc0000000008 RBX: 0000000000000003 RCX: ffffffff8159bc3e > >> RDX: 0000000000000000 RSI: 1ffff100381dcdc8 RDI: ffff8801db317dd0 > >> RBP: ffff8801c0ee70a8 R08: 0000000000000000 R09: 1ffff100381dcd9a > >> R10: ffffed00381dce3c R11: ffffffff86137ad8 R12: 0000000000000001 > >> R13: ffffffff86113480 R14: ffffffff8560dc40 R15: ffffffff8146e5f0 > >> __debug_check_no_obj_freed lib/debugobjects.c:745 [inline] > >> debug_check_no_obj_freed+0x662/0xf1f lib/debugobjects.c:774 > >> kmem_cache_free+0x253/0x2a0 mm/slab.c:3745 > > > > I believe we just need to defer kmem_cache_free to call_rcu. > > > Hi Tom, > > Was this ever submitted? I don't any such change in net/kcm/kcmsock.c.
Hi Dmitry, I am looking at it. Not yet convinced that call_rcu is right fix. Tom
