/* * sctp_probe - Observe the SCTP flow with kprobes. * * The idea for this came from Werner Almesberger's umlsim * Copyright (C) 2004, Stephen Hemminger * * Modified for SCTP from Stephen Hemminger's code * Copyright (C) 2010, Wei Yongjun * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include MODULE_SOFTDEP("pre: sctp"); MODULE_AUTHOR("Wei Yongjun "); MODULE_DESCRIPTION("SCTP snooper"); MODULE_LICENSE("GPL"); static int port __read_mostly = 0; MODULE_PARM_DESC(port, "Port to match (0=all)"); module_param(port, int, 0); static unsigned int fwmark __read_mostly = 0; MODULE_PARM_DESC(fwmark, "skb mark to match (0=no mark)"); module_param(fwmark, uint, 0); static int bufsize __read_mostly = 64 * 1024; MODULE_PARM_DESC(bufsize, "Log buffer size (default 64k)"); module_param(bufsize, int, 0); static int full __read_mostly = 1; MODULE_PARM_DESC(full, "Full log (1=every ack packet received, 0=only cwnd changes)"); module_param(full, int, 0); static const char procname[] = "sctpprobe"; static struct { struct kfifo fifo; spinlock_t lock; wait_queue_head_t wait; struct timespec64 tstart; } sctpw; static __printf(1, 2) void printl(const char *fmt, ...) { va_list args; int len; char tbuf[256]; va_start(args, fmt); len = vscnprintf(tbuf, sizeof(tbuf), fmt, args); va_end(args); kfifo_in_locked(&sctpw.fifo, tbuf, len, &sctpw.lock); wake_up(&sctpw.wait); } static int sctpprobe_open(struct inode *inode, struct file *file) { kfifo_reset(&sctpw.fifo); ktime_get_ts64(&sctpw.tstart); return 0; } static ssize_t sctpprobe_read(struct file *file, char __user *buf, size_t len, loff_t *ppos) { int error = 0, cnt = 0; unsigned char *tbuf; if (!buf) return -EINVAL; if (len == 0) return 0; tbuf = vmalloc(len); if (!tbuf) return -ENOMEM; error = wait_event_interruptible(sctpw.wait, kfifo_len(&sctpw.fifo) != 0); if (error) goto out_free; cnt = kfifo_out_locked(&sctpw.fifo, tbuf, len, &sctpw.lock); error = copy_to_user(buf, tbuf, cnt) ? -EFAULT : 0; out_free: vfree(tbuf); return error ? error : cnt; } static const struct file_operations sctpprobe_fops = { .owner = THIS_MODULE, .open = sctpprobe_open, .read = sctpprobe_read, .llseek = noop_llseek, }; static sctp_disposition_t jsctp_sf_eat_sack(struct net *net, const struct sctp_endpoint *ep, const struct sctp_association *asoc, const sctp_subtype_t type, void *arg, sctp_cmd_seq_t *commands) { struct sctp_chunk *chunk = arg; struct sk_buff *skb = chunk->skb; struct sctp_transport *sp; static __u32 lcwnd = 0; struct timespec64 now; sp = asoc->peer.primary_path; if (((port == 0 && fwmark == 0) || asoc->peer.port == port || ep->base.bind_addr.port == port || (fwmark > 0 && skb->mark == fwmark)) && (full || sp->cwnd != lcwnd)) { lcwnd = sp->cwnd; ktime_get_ts64(&now); now = timespec64_sub(now, sctpw.tstart); printl("%lu.%06lu ", (unsigned long) now.tv_sec, (unsigned long) now.tv_nsec / NSEC_PER_USEC); printl("%p %5d %5d %5d %8d %5d ", asoc, ep->base.bind_addr.port, asoc->peer.port, asoc->pathmtu, asoc->peer.rwnd, asoc->unack_data); list_for_each_entry(sp, &asoc->peer.transport_addr_list, transports) { if (sp == asoc->peer.primary_path) printl("*"); printl("%pISc %2u %8u %8u %8u %8u %8u ", &sp->ipaddr, sp->state, sp->cwnd, sp->ssthresh, sp->flight_size, sp->partial_bytes_acked, sp->pathmtu); } printl("\n"); } jprobe_return(); return 0; } static struct jprobe sctp_recv_probe = { .kp = { .symbol_name = "sctp_sf_eat_sack_6_2", }, .entry = jsctp_sf_eat_sack, }; static __init int sctp_setup_jprobe(void) { int ret = register_jprobe(&sctp_recv_probe); if (ret) { if (request_module("sctp")) goto out; ret = register_jprobe(&sctp_recv_probe); } out: return ret; } static __init int sctpprobe_init(void) { int ret = -ENOMEM; /* Warning: if the function signature of sctp_sf_eat_sack_6_2, * has been changed, you also have to change the signature of * jsctp_sf_eat_sack, otherwise you end up right here! */ BUILD_BUG_ON(__same_type(sctp_sf_eat_sack_6_2, jsctp_sf_eat_sack) == 0); init_waitqueue_head(&sctpw.wait); spin_lock_init(&sctpw.lock); if (kfifo_alloc(&sctpw.fifo, bufsize, GFP_KERNEL)) return ret; if (!proc_create(procname, S_IRUSR, init_net.proc_net, &sctpprobe_fops)) goto free_kfifo; ret = sctp_setup_jprobe(); if (ret) goto remove_proc; pr_info("probe registered (port=%d/fwmark=%u) bufsize=%u\n", port, fwmark, bufsize); return 0; remove_proc: remove_proc_entry(procname, init_net.proc_net); free_kfifo: kfifo_free(&sctpw.fifo); return ret; } static __exit void sctpprobe_exit(void) { kfifo_free(&sctpw.fifo); remove_proc_entry(procname, init_net.proc_net); unregister_jprobe(&sctp_recv_probe); } module_init(sctpprobe_init); module_exit(sctpprobe_exit); eb5804d295203c302d496d8ee91'>a0615a16f7d0ceb5804d295203c302d496d8ee91 (diff)
powerpc/mm: Fix spurrious segfaults on radix with autonuma
When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'net/ipv4/af_inet.c')