/* * netsniff-ng - the packet sniffing beast * Copyright 2011 Daniel Borkmann. * Subject to the GPL, version 2. */ #include #include #include #include #include #include #include "die.h" #include "str.h" #include "built_in.h" #include "locking.h" #include "xmalloc.h" #include "curvetun.h" #include "curve.h" #include "curvetun_mgmt_servers.h" #include "crypto.h" struct server_store { int udp; char alias[256]; char host[256]; char port[6]; /* 5 + \0 */ unsigned char publickey[crypto_box_pub_key_size]; struct curve25519_proto proto_inf; unsigned char auth_token[crypto_auth_hmacsha512256_KEYBYTES]; struct server_store *next; }; static struct server_store *store = NULL; static struct server_store *selected = NULL; static struct rwlock store_lock; static struct server_store *server_store_alloc(void) { return xzmalloc(sizeof(struct server_store)); } static void server_store_free(struct server_store *ss) { if (!ss) return; memset(ss, 0, sizeof(struct server_store)); xfree(ss); } enum parse_states { PARSE_ALIAS, PARSE_SERVER, PARSE_PORT, PARSE_CARRIER, PARSE_PUBKEY, PARSE_DONE, }; static int parse_line(char *line, char *homedir) { char *str; enum parse_states s = PARSE_ALIAS; struct server_store *elem; unsigned char pkey[crypto_box_pub_key_size]; elem = server_store_alloc(); elem->next = store; str = strtok(line, ";"); for (; str != NULL;) { switch (s) { case PARSE_ALIAS: strlcpy(elem->alias, str, sizeof(elem->alias)); s = PARSE_SERVER; break; case PARSE_SERVER: strlcpy(elem->host, str, sizeof(elem->host)); s = PARSE_PORT; break; case PARSE_PORT: strlcpy(elem->port, str, sizeof(elem->port)); s = PARSE_CARRIER; break; case PARSE_CARRIER: if (!strncmp("udp", str, strlen("udp"))) elem->udp = 1; else if (!strncmp("tcp", str, strlen("tcp"))) elem->udp = 0; else { syslog(LOG_ERR, "Incorrect carrier type !(udp|tcp) in server spec.\n"); return -EIO; } s = PARSE_PUBKEY; break; case PARSE_PUBKEY: if (!curve25519_pubkey_hexparse_32(pkey, sizeof(pkey), str, strlen(str))) return -EINVAL; memcpy(elem->publickey, pkey, sizeof(elem->publickey)); memcpy(elem->auth_token, pkey, sizeof(elem->auth_token)); curve25519_proto_init(&elem->proto_inf, elem->publickey, sizeof(elem->publickey)); s = PARSE_DONE; break; case PARSE_DONE: break; default: return -EIO; } str = strtok(NULL, ";"); } store = elem; return s == PARSE_DONE ? 0 : -EIO; } void parse_userfile_and_generate_serv_store_or_die(char *homedir) { FILE *fp; char path[PATH_MAX], buff[1024]; int line = 1, ret; memset(path, 0, sizeof(path)); slprintf(path, sizeof(path), "%s/%s", homedir, FILE_SERVERS); rwlock_init(&store_lock); rwlock_wr_lock(&store_lock); fp = fopen(path, "r"); if (!fp) panic("Cannot open server file!\n"); memset(buff, 0, sizeof(buff)); while (fgets(buff, sizeof(buff), fp) != NULL) { buff[sizeof(buff) - 1] = 0; /* A comment. Skip this line */ if (buff[0] == '#' || buff[0] == '\n') { memset(buff, 0, sizeof(buff)); line++; continue; } ret = parse_line(buff, homedir); if (ret < 0) panic("Cannot parse line %d from clients!\n", line); line++; memset(buff, 0, sizeof(buff)); } fclose(fp); if (store == NULL) panic("No registered servers found!\n"); rwlock_unlock(&store_lock); } void dump_serv_store(void) { int i; struct server_store *elem; rwlock_rd_lock(&store_lock); elem = store; while (elem) { printf("[%s] -> %s:%s via %s -> ", elem->alias, elem->host, elem->port, elem->udp ? "udp" : "tcp"); for (i = 0; i < sizeof(elem->publickey); ++i) if (i == (sizeof(elem->publickey) - 1)) printf("%02x\n", (unsigned char) elem->publickey[i]); else printf("%02x:", (unsigned char) elem->publickey[i]); elem = elem->next; } rwlock_unlock(&store_lock); } void destroy_serv_store(void) { struct server_store *elem, *nelem = NULL; rwlock_wr_lock(&store_lock); selected = NULL; elem = store; while (elem) { nelem = elem->next; elem->next = NULL; server_store_free(elem); elem = nelem; } rwlock_unlock(&store_lock); rwlock_destroy(&store_lock); } void get_serv_store_entry_by_alias(char *alias, size_t len, char **host, char **port, int *udp) { struct server_store *elem; rwlock_rd_lock(&store_lock); elem = store; if (!alias) { while (elem && elem->next) elem = elem->next; if (elem) { (*host) = elem->host; (*port) = elem->port; (*udp) = elem->udp; selected = elem; } else { rwlock_unlock(&store_lock); goto nothing; } } else { while (elem) { if (!strncmp(elem->alias, alias, min(len, strlen(elem->alias) + 1))) break; elem = elem->next; } if (elem) { (*host) = elem->host; (*port) = elem->port; (*udp) = elem->udp; selected = elem; } else { rwlock_unlock(&store_lock); goto nothing; } } rwlock_unlock(&store_lock); return; nothing: (*host) = NULL; (*port) = NULL; (*udp) = -1; } struct curve25519_proto *get_serv_store_entry_proto_inf(void) { struct curve25519_proto *ret = NULL; rwlock_rd_lock(&store_lock); if (selected) ret = &selected->proto_inf; rwlock_unlock(&store_lock); return ret; } unsigned char *get_serv_store_entry_auth_token(void) { unsigned char *ret = NULL; rwlock_rd_lock(&store_lock); if (selected) ret = selected->auth_token; rwlock_unlock(&store_lock); return ret; } 6c543e55b6672d5a37e'>patch) tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /tools/build/Documentation 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/build/Documentation')