/* * netsniff-ng - the packet sniffing beast * Copyright 2011 - 2013 Daniel Borkmann. * Subject to the GPL, version 2. */ #include #include #include #include #include #include #include "pcap_io.h" #include "xmalloc.h" #include "built_in.h" #include "iosched.h" #include "ioops.h" static struct iovec iov[1024] __cacheline_aligned; static off_t iov_off_rd = 0, iov_slot = 0; static ssize_t pcap_sg_write(int fd, pcap_pkthdr_t *phdr, enum pcap_type type, const uint8_t *packet, size_t len) { ssize_t ret, hdrsize = pcap_get_hdr_length(phdr, type); if (unlikely(iov_slot == array_size(iov))) { ret = writev(fd, iov, array_size(iov)); if (ret < 0) panic("Writev I/O error: %s!\n", strerror(errno)); iov_slot = 0; } memcpy(iov[iov_slot].iov_base, &phdr->raw, hdrsize); iov[iov_slot].iov_len = hdrsize; memcpy(iov[iov_slot].iov_base + iov[iov_slot].iov_len, packet, len); ret = (iov[iov_slot].iov_len += len); iov_slot++; return ret; } static ssize_t __pcap_sg_inter_iov_hdr_read(int fd, pcap_pkthdr_t *phdr, size_t hdrsize) { int ret; size_t offset = 0; ssize_t remainder; offset = iov[iov_slot].iov_len - iov_off_rd; remainder = hdrsize - offset; if (remainder < 0) remainder = 0; bug_on(offset + remainder != hdrsize); memcpy(&phdr->raw, iov[iov_slot].iov_base + iov_off_rd, offset); iov_off_rd = 0; iov_slot++; if (iov_slot == array_size(iov)) { iov_slot = 0; ret = readv(fd, iov, array_size(iov)); if (unlikely(ret <= 0)) return -EIO; } memcpy(&phdr->raw + offset, iov[iov_slot].iov_base + iov_off_rd, remainder); iov_off_rd += remainder; return hdrsize; } static ssize_t __pcap_sg_inter_iov_data_read(int fd, uint8_t *packet, size_t hdrlen) { int ret; size_t offset = 0; ssize_t remainder; offset = iov[iov_slot].iov_len - iov_off_rd; remainder = hdrlen - offset; if (remainder < 0) remainder = 0; bug_on(offset + remainder != hdrlen); memcpy(packet, iov[iov_slot].iov_base + iov_off_rd, offset); iov_off_rd = 0; iov_slot++; if (iov_slot == array_size(iov)) { iov_slot = 0; ret = readv(fd, iov, array_size(iov)); if (unlikely(ret <= 0)) return -EIO; } memcpy(packet + offset, iov[iov_slot].iov_base + iov_off_rd, remainder); iov_off_rd += remainder; return hdrlen; } static ssize_t pcap_sg_read(int fd, pcap_pkthdr_t *phdr, enum pcap_type type, uint8_t *packet, size_t len) { ssize_t ret = 0; size_t hdrsize = pcap_get_hdr_length(phdr, type), hdrlen; if (likely(iov[iov_slot].iov_len - iov_off_rd >= hdrsize)) { memcpy(&phdr->raw, iov[iov_slot].iov_base + iov_off_rd, hdrsize); iov_off_rd += hdrsize; } else { ret = __pcap_sg_inter_iov_hdr_read(fd, phdr, hdrsize); if (unlikely(ret < 0)) return ret; } hdrlen = pcap_get_length(phdr, type); if (unlikely(hdrlen == 0 || hdrlen > len)) return -EINVAL; if (likely(iov[iov_slot].iov_len - iov_off_rd >= hdrlen)) { memcpy(packet, iov[iov_slot].iov_base + iov_off_rd, hdrlen); iov_off_rd += hdrlen; } else { ret = __pcap_sg_inter_iov_data_read(fd, packet, hdrlen); if (unlikely(ret < 0)) return ret; } return hdrsize + hdrlen; } static void pcap_sg_fsync(int fd) { ssize_t ret = writev(fd, iov, iov_slot); if (ret < 0) panic("Writev I/O error: %s!\n", strerror(errno)); iov_slot = 0; fdatasync(fd); } static void pcap_sg_init_once(bool enforce_prio) { if (enforce_prio) set_ioprio_rt(); } static int pcap_sg_prepare_access(int fd, enum pcap_mode mode, bool jumbo) { int ret; size_t i, len = 0; iov_slot = 0; len = jumbo ? (RUNTIME_PAGE_SIZE * 16) /* 64k max */ : (RUNTIME_PAGE_SIZE * 3) /* 12k max */; for (i = 0; i < array_size(iov); ++i) { iov[i].iov_base = xzmalloc_aligned(len, 64); iov[i].iov_len = len; } if (mode == PCAP_MODE_RD) { ret = readv(fd, iov, array_size(iov)); if (ret <= 0) return -EIO; iov_off_rd = 0; iov_slot = 0; } return 0; } static void pcap_sg_prepare_close(int fd __maybe_unused, enum pcap_mode mode __maybe_unused) { size_t i; for (i = 0; i < array_size(iov); ++i) xfree(iov[i].iov_base); } const struct pcap_file_ops pcap_sg_ops = { .init_once_pcap = pcap_sg_init_once, .pull_fhdr_pcap = pcap_generic_pull_fhdr, .push_fhdr_pcap = pcap_generic_push_fhdr, .prepare_access_pcap = pcap_sg_prepare_access, .prepare_close_pcap = pcap_sg_prepare_close, .read_pcap = pcap_sg_read, .write_pcap = pcap_sg_write, .fsync_pcap = pcap_sg_fsync, }; lue='35'>35space:mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800
commit39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch)
tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /tools/testing/selftests/futex/functional/.gitignore
parent2c5d9555d6d937966d79d4c6529a5f7b9206e405 (diff)
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'tools/testing/selftests/futex/functional/.gitignore')