X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fjournal%2Fjournald-native.c;h=d3735ec73c598706516355aae48239c81afc7bb4;hp=f878dfc911a719a0501f961264a2e9b228f5d905;hb=73843b52585d42cc1a970a1c664818ece6942e9e;hpb=f6422def2c10aa0dea1b872d2f187853e61bd015 diff --git a/src/journal/journald-native.c b/src/journal/journald-native.c index f878dfc91..d3735ec73 100644 --- a/src/journal/journald-native.c +++ b/src/journal/journald-native.c @@ -22,21 +22,20 @@ #include #include #include +#include #include "socket-util.h" #include "path-util.h" +#include "selinux-util.h" #include "journald-server.h" #include "journald-native.h" #include "journald-kmsg.h" #include "journald-console.h" #include "journald-syslog.h" +#include "journald-wall.h" +#include "memfd.h" -/* Make sure not to make this smaller than the maximum coredump - * size. See COREDUMP_MAX in coredump.c */ -#define ENTRY_SIZE_MAX (1024*1024*768) -#define DATA_SIZE_MAX (1024*1024*768) - -static bool valid_user_field(const char *p, size_t l) { +bool valid_user_field(const char *p, size_t l, bool allow_protected) { const char *a; /* We kinda enforce POSIX syntax recommendations for @@ -54,7 +53,7 @@ static bool valid_user_field(const char *p, size_t l) { return false; /* Variables starting with an underscore are protected */ - if (p[0] == '_') + if (!allow_protected && p[0] == '_') return false; /* Don't allow digits as first character */ @@ -63,14 +62,18 @@ static bool valid_user_field(const char *p, size_t l) { /* Only allow A-Z0-9 and '_' */ for (a = p; a < p + l; a++) - if (!((*a >= 'A' && *a <= 'Z') || - (*a >= '0' && *a <= '9') || - *a == '_')) + if ((*a < 'A' || *a > 'Z') && + (*a < '0' || *a > '9') && + *a != '_') return false; return true; } +static bool allow_object_pid(struct ucred *ucred) { + return ucred && ucred->uid == 0; +} + void server_process_native_message( Server *s, const void *buffer, size_t buffer_size, @@ -79,11 +82,12 @@ void server_process_native_message( const char *label, size_t label_len) { struct iovec *iovec = NULL; - unsigned n = 0, m = 0, j, tn = (unsigned) -1; + unsigned n = 0, j, tn = (unsigned) -1; const char *p; - size_t remaining; + size_t remaining, m = 0, entry_size = 0; int priority = LOG_INFO; char *identifier = NULL, *message = NULL; + pid_t object_pid = 0; assert(s); assert(buffer || buffer_size == 0); @@ -104,9 +108,16 @@ void server_process_native_message( if (e == p) { /* Entry separator */ - server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority); + + if (entry_size + n + 1 > ENTRY_SIZE_MAX) { /* data + separators + trailer */ + log_debug("Entry is too big with %u properties and %zu bytes, ignoring.", n, entry_size); + continue; + } + + server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid); n = 0; priority = LOG_INFO; + entry_size = 0; p++; remaining--; @@ -124,24 +135,14 @@ void server_process_native_message( /* A property follows */ /* n received properties, +1 for _TRANSPORT */ - if (n + 1 + N_IOVEC_META_FIELDS >= m) { - struct iovec *c; - unsigned u; - - u = MAX((n + 1 + N_IOVEC_META_FIELDS) * 2U, 4U); - c = realloc(iovec, u * sizeof(struct iovec)); - if (!c) { - log_oom(); - break; - } - - iovec = c; - m = u; + if (!GREEDY_REALLOC(iovec, m, n + 1 + N_IOVEC_META_FIELDS + !!object_pid * N_IOVEC_OBJECT_FIELDS)) { + log_oom(); + break; } q = memchr(p, '=', e - p); if (q) { - if (valid_user_field(p, q - p)) { + if (valid_user_field(p, q - p, false)) { size_t l; l = e - p; @@ -152,29 +153,30 @@ void server_process_native_message( * field */ iovec[n].iov_base = (char*) p; iovec[n].iov_len = l; + entry_size += iovec[n].iov_len; n++; /* We need to determine the priority * of this entry for the rate limiting * logic */ if (l == 10 && - memcmp(p, "PRIORITY=", 9) == 0 && + startswith(p, "PRIORITY=") && p[9] >= '0' && p[9] <= '9') priority = (priority & LOG_FACMASK) | (p[9] - '0'); else if (l == 17 && - memcmp(p, "SYSLOG_FACILITY=", 16) == 0 && + startswith(p, "SYSLOG_FACILITY=") && p[16] >= '0' && p[16] <= '9') priority = (priority & LOG_PRIMASK) | ((p[16] - '0') << 3); else if (l == 18 && - memcmp(p, "SYSLOG_FACILITY=", 16) == 0 && + startswith(p, "SYSLOG_FACILITY=") && p[16] >= '0' && p[16] <= '9' && p[17] >= '0' && p[17] <= '9') priority = (priority & LOG_PRIMASK) | (((p[16] - '0')*10 + (p[17] - '0')) << 3); else if (l >= 19 && - memcmp(p, "SYSLOG_IDENTIFIER=", 18) == 0) { + startswith(p, "SYSLOG_IDENTIFIER=")) { char *t; t = strndup(p + 18, l - 18); @@ -183,7 +185,7 @@ void server_process_native_message( identifier = t; } } else if (l >= 8 && - memcmp(p, "MESSAGE=", 8) == 0) { + startswith(p, "MESSAGE=")) { char *t; t = strndup(p + 8, l - 8); @@ -191,6 +193,16 @@ void server_process_native_message( free(message); message = t; } + } else if (l > strlen("OBJECT_PID=") && + l < strlen("OBJECT_PID=") + DECIMAL_STR_MAX(pid_t) && + startswith(p, "OBJECT_PID=") && + allow_object_pid(ucred)) { + char buf[DECIMAL_STR_MAX(pid_t)]; + memcpy(buf, p + strlen("OBJECT_PID="), l - strlen("OBJECT_PID=")); + char_array_0(buf); + + /* ignore error */ + parse_pid(buf, &object_pid); } } @@ -211,7 +223,7 @@ void server_process_native_message( l = le64toh(l_le); if (l > DATA_SIZE_MAX) { - log_debug("Received binary data block too large, ignoring."); + log_debug("Received binary data block of %"PRIu64" bytes is too large, ignoring.", l); break; } @@ -231,9 +243,10 @@ void server_process_native_message( k[e - p] = '='; memcpy(k + (e - p) + 1, e + 1 + sizeof(uint64_t), l); - if (valid_user_field(p, e - p)) { + if (valid_user_field(p, e - p, false)) { iovec[n].iov_base = k; iovec[n].iov_len = (e - p) + 1 + l; + entry_size += iovec[n].iov_len; n++; } else free(k); @@ -248,6 +261,13 @@ void server_process_native_message( tn = n++; IOVEC_SET_STRING(iovec[tn], "_TRANSPORT=journal"); + entry_size += strlen("_TRANSPORT=journal"); + + if (entry_size + n + 1 > ENTRY_SIZE_MAX) { /* data + separators + trailer */ + log_debug("Entry is too big with %u properties and %zu bytes, ignoring.", + n, entry_size); + goto finish; + } if (message) { if (s->forward_to_syslog) @@ -258,9 +278,12 @@ void server_process_native_message( if (s->forward_to_console) server_forward_console(s, priority, identifier, message, ucred); + + if (s->forward_to_wall) + server_forward_wall(s, priority, identifier, message, ucred); } - server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority); + server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid); finish: for (j = 0; j < n; j++) { @@ -285,17 +308,27 @@ void server_process_native_file( const char *label, size_t label_len) { struct stat st; - _cleanup_free_ void *p = NULL; - ssize_t n; + bool sealed; int r; + /* Data is in the passed fd, since it didn't fit in a + * datagram. */ + assert(s); assert(fd >= 0); - if (!ucred || ucred->uid != 0) { + /* If it's a memfd, check if it is sealed. If so, we can just + * use map it and use it, and do not need to copy the data + * out. */ + sealed = memfd_get_sealed(fd) > 0; + + if (!sealed && (!ucred || ucred->uid != 0)) { _cleanup_free_ char *sl = NULL, *k = NULL; const char *e; + /* If this is not a sealed memfd, and the peer is unknown or + * unprivileged, then verify the path. */ + if (asprintf(&sl, "/proc/self/fd/%i", fd) < 0) { log_oom(); return; @@ -323,11 +356,6 @@ void server_process_native_file( } } - /* Data is in the passed file, since it didn't fit in a - * datagram. We can't map the file here, since clients might - * then truncate it and trigger a SIGBUS for us. So let's - * stupidly read it */ - if (fstat(fd, &st) < 0) { log_error("Failed to stat passed file, ignoring: %m"); return; @@ -346,27 +374,53 @@ void server_process_native_file( return; } - p = malloc(st.st_size); - if (!p) { - log_oom(); - return; - } + if (sealed) { + void *p; + size_t ps; + + /* The file is sealed, we can just map it and use it. */ + + ps = PAGE_ALIGN(st.st_size); + p = mmap(NULL, ps, PROT_READ, MAP_PRIVATE, fd, 0); + if (p == MAP_FAILED) { + log_error("Failed to map memfd, ignoring: %m"); + return; + } + + server_process_native_message(s, p, st.st_size, ucred, tv, label, label_len); + assert_se(munmap(p, ps) >= 0); + } else { + _cleanup_free_ void *p = NULL; + ssize_t n; - n = pread(fd, p, st.st_size, 0); - if (n < 0) - log_error("Failed to read file, ignoring: %s", strerror(-n)); - else if (n > 0) - server_process_native_message(s, p, n, ucred, tv, label, label_len); + /* The file is not sealed, we can't map the file here, since + * clients might then truncate it and trigger a SIGBUS for + * us. So let's stupidly read it */ + + p = malloc(st.st_size); + if (!p) { + log_oom(); + return; + } + + n = pread(fd, p, st.st_size, 0); + if (n < 0) + log_error("Failed to read file, ignoring: %s", strerror(-n)); + else if (n > 0) + server_process_native_message(s, p, n, ucred, tv, label, label_len); + } } int server_open_native_socket(Server*s) { - union sockaddr_union sa; int one, r; - struct epoll_event ev; assert(s); if (s->native_fd < 0) { + union sockaddr_union sa = { + .un.sun_family = AF_UNIX, + .un.sun_path = "/run/systemd/journal/socket", + }; s->native_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); if (s->native_fd < 0) { @@ -374,15 +428,11 @@ int server_open_native_socket(Server*s) { return -errno; } - zero(sa); - sa.un.sun_family = AF_UNIX; - strncpy(sa.un.sun_path, "/run/systemd/journal/socket", sizeof(sa.un.sun_path)); - unlink(sa.un.sun_path); r = bind(s->native_fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path)); if (r < 0) { - log_error("bind() failed: %m"); + log_error("bind(%s) failed: %m", sa.un.sun_path); return -errno; } @@ -398,10 +448,12 @@ int server_open_native_socket(Server*s) { } #ifdef HAVE_SELINUX - one = 1; - r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one)); - if (r < 0) - log_warning("SO_PASSSEC failed: %m"); + if (mac_selinux_use()) { + one = 1; + r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one)); + if (r < 0) + log_warning("SO_PASSSEC failed: %m"); + } #endif one = 1; @@ -411,12 +463,10 @@ int server_open_native_socket(Server*s) { return -errno; } - zero(ev); - ev.events = EPOLLIN; - ev.data.fd = s->native_fd; - if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, s->native_fd, &ev) < 0) { - log_error("Failed to add native server fd to epoll object: %m"); - return -errno; + r = sd_event_add_io(s->event, &s->native_event_source, s->native_fd, EPOLLIN, process_datagram, s); + if (r < 0) { + log_error("Failed to add native server fd to event loop: %s", strerror(-r)); + return r; } return 0;