| Message ID | 156538726702.16201.13552536596121161945.stgit@warthog.procyon.org.uk |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net] rxrpc: Fix local refcounting | expand |
David, Looks good to me. You can add a Reviewed-by line. Thanks. Jeffrey Altman On 8/9/2019 5:47 PM, David Howells wrote: > Fix rxrpc_unuse_local() to handle a NULL local pointer as it can be called > on an unbound socket on which rx->local is not yet set. > > The following reproduced (includes omitted): > > int main(void) > { > socket(AF_RXRPC, SOCK_DGRAM, AF_INET); > return 0; > } > > causes the following oops to occur: > > BUG: kernel NULL pointer dereference, address: 0000000000000010 > ... > RIP: 0010:rxrpc_unuse_local+0x8/0x1b > ... > Call Trace: > rxrpc_release+0x2b5/0x338 > __sock_release+0x37/0xa1 > sock_close+0x14/0x17 > __fput+0x115/0x1e9 > task_work_run+0x72/0x98 > do_exit+0x51b/0xa7a > ? __context_tracking_exit+0x4e/0x10e > do_group_exit+0xab/0xab > __x64_sys_exit_group+0x14/0x17 > do_syscall_64+0x89/0x1d4 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > Reported-by: syzbot+20dee719a2e090427b5f@syzkaller.appspotmail.com > Fixes: 730c5fd42c1e ("rxrpc: Fix local endpoint refcounting") > Signed-off-by: David Howells <dhowells@redhat.com> > cc: Jeffrey Altman <jaltman@auristor.com> > --- > > net/rxrpc/local_object.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c > index 9798159ee65f..c9db3e762d8d 100644 > --- a/net/rxrpc/local_object.c > +++ b/net/rxrpc/local_object.c > @@ -402,11 +402,13 @@ void rxrpc_unuse_local(struct rxrpc_local *local) > { > unsigned int au; > > - au = atomic_dec_return(&local->active_users); > - if (au == 0) > - rxrpc_queue_local(local); > - else > - rxrpc_put_local(local); > + if (local) { > + au = atomic_dec_return(&local->active_users); > + if (au == 0) > + rxrpc_queue_local(local); > + else > + rxrpc_put_local(local); > + } > } > > /* >
From: David Howells <dhowells@redhat.com> Date: Fri, 09 Aug 2019 22:47:47 +0100 > Fix rxrpc_unuse_local() to handle a NULL local pointer as it can be called > on an unbound socket on which rx->local is not yet set. > > The following reproduced (includes omitted): > > int main(void) > { > socket(AF_RXRPC, SOCK_DGRAM, AF_INET); > return 0; > } > > causes the following oops to occur: > > BUG: kernel NULL pointer dereference, address: 0000000000000010 > ... > RIP: 0010:rxrpc_unuse_local+0x8/0x1b > ... > Call Trace: > rxrpc_release+0x2b5/0x338 > __sock_release+0x37/0xa1 > sock_close+0x14/0x17 > __fput+0x115/0x1e9 > task_work_run+0x72/0x98 > do_exit+0x51b/0xa7a > ? __context_tracking_exit+0x4e/0x10e > do_group_exit+0xab/0xab > __x64_sys_exit_group+0x14/0x17 > do_syscall_64+0x89/0x1d4 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > Reported-by: syzbot+20dee719a2e090427b5f@syzkaller.appspotmail.com > Fixes: 730c5fd42c1e ("rxrpc: Fix local endpoint refcounting") > Signed-off-by: David Howells <dhowells@redhat.com> > cc: Jeffrey Altman <jaltman@auristor.com> Applied.
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c index 9798159ee65f..c9db3e762d8d 100644 --- a/net/rxrpc/local_object.c +++ b/net/rxrpc/local_object.c @@ -402,11 +402,13 @@ void rxrpc_unuse_local(struct rxrpc_local *local) { unsigned int au; - au = atomic_dec_return(&local->active_users); - if (au == 0) - rxrpc_queue_local(local); - else - rxrpc_put_local(local); + if (local) { + au = atomic_dec_return(&local->active_users); + if (au == 0) + rxrpc_queue_local(local); + else + rxrpc_put_local(local); + } } /*
Fix rxrpc_unuse_local() to handle a NULL local pointer as it can be called on an unbound socket on which rx->local is not yet set. The following reproduced (includes omitted): int main(void) { socket(AF_RXRPC, SOCK_DGRAM, AF_INET); return 0; } causes the following oops to occur: BUG: kernel NULL pointer dereference, address: 0000000000000010 ... RIP: 0010:rxrpc_unuse_local+0x8/0x1b ... Call Trace: rxrpc_release+0x2b5/0x338 __sock_release+0x37/0xa1 sock_close+0x14/0x17 __fput+0x115/0x1e9 task_work_run+0x72/0x98 do_exit+0x51b/0xa7a ? __context_tracking_exit+0x4e/0x10e do_group_exit+0xab/0xab __x64_sys_exit_group+0x14/0x17 do_syscall_64+0x89/0x1d4 entry_SYSCALL_64_after_hwframe+0x49/0xbe Reported-by: syzbot+20dee719a2e090427b5f@syzkaller.appspotmail.com Fixes: 730c5fd42c1e ("rxrpc: Fix local endpoint refcounting") Signed-off-by: David Howells <dhowells@redhat.com> cc: Jeffrey Altman <jaltman@auristor.com> --- net/rxrpc/local_object.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)