diff --git a/CHANGELOG b/CHANGELOG index 2c9aebbb..3bf40441 100644 --- a/CHANGELOG +++ b/CHANGELOG @@ -152,6 +152,9 @@ HISTORY ++ Bugfixes: + 2015-01-17: Simon Goldschmidt + * sockets.c: fixed bug #43361 select() crashes with stale FDs + 2015-01-17: Simon Goldschmidt * sockets.c/.h, memp_std.h: fixed bug #40788 "lwip_setsockopt_internal() crashes" by rewriting set/getsockopt functions to combine checks with the actual code diff --git a/src/api/sockets.c b/src/api/sockets.c index 3369c6d1..4109cee4 100644 --- a/src/api/sockets.c +++ b/src/api/sockets.c @@ -1209,6 +1209,7 @@ lwip_select(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset, u32_t msectimeout; struct lwip_select_cb select_cb; int i; + int maxfdp2; SYS_ARCH_DECL_PROTECT(lev); LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select(%d, %p, %p, %p, tvsec=%"S32_F" tvusec=%"S32_F")\n", @@ -1266,47 +1267,69 @@ lwip_select(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset, SYS_ARCH_UNPROTECT(lev); /* Increase select_waiting for each socket we are interested in */ - for(i = 0; i < maxfdp1; i++) { + maxfdp2 = maxfdp1; + for (i = 0; i < maxfdp1; i++) { if ((readset && FD_ISSET(i, readset)) || (writeset && FD_ISSET(i, writeset)) || (exceptset && FD_ISSET(i, exceptset))) { - struct lwip_sock *sock = tryget_socket(i); - LWIP_ASSERT("sock != NULL", sock != NULL); + struct lwip_sock *sock; SYS_ARCH_PROTECT(lev); - sock->select_waiting++; - LWIP_ASSERT("sock->select_waiting overflow", sock->select_waiting > 0); + sock = tryget_socket(i); + if (sock != NULL) { + sock->select_waiting++; + LWIP_ASSERT("sock->select_waiting > 0", sock->select_waiting > 0); + } else { + /* Not a valid socket */ + nready = -1; + maxfdp2 = i; + SYS_ARCH_UNPROTECT(lev); + break; + } SYS_ARCH_UNPROTECT(lev); } } - /* Call lwip_selscan again: there could have been events between - the last scan (without us on the list) and putting us on the list! */ - nready = lwip_selscan(maxfdp1, readset, writeset, exceptset, &lreadset, &lwriteset, &lexceptset); - if (!nready) { - /* Still none ready, just wait to be woken */ - if (timeout == 0) { - /* Wait forever */ - msectimeout = 0; - } else { - msectimeout = ((timeout->tv_sec * 1000) + ((timeout->tv_usec + 500)/1000)); - if (msectimeout == 0) { - /* Wait 1ms at least (0 means wait forever) */ - msectimeout = 1; + if (nready >= 0) { + /* Call lwip_selscan again: there could have been events between + the last scan (without us on the list) and putting us on the list! */ + nready = lwip_selscan(maxfdp1, readset, writeset, exceptset, &lreadset, &lwriteset, &lexceptset); + if (!nready) { + /* Still none ready, just wait to be woken */ + if (timeout == 0) { + /* Wait forever */ + msectimeout = 0; + } else { + msectimeout = ((timeout->tv_sec * 1000) + ((timeout->tv_usec + 500)/1000)); + if (msectimeout == 0) { + /* Wait 1ms at least (0 means wait forever) */ + msectimeout = 1; + } } - } - waitres = sys_arch_sem_wait(SELECT_SEM_PTR(select_cb.sem), msectimeout); + waitres = sys_arch_sem_wait(SELECT_SEM_PTR(select_cb.sem), msectimeout); + } } - /* Increase select_waiting for each socket we are interested in */ - for(i = 0; i < maxfdp1; i++) { + + /* Decrease select_waiting for each socket we are interested in */ + for (i = 0; i < maxfdp2; i++) { if ((readset && FD_ISSET(i, readset)) || (writeset && FD_ISSET(i, writeset)) || (exceptset && FD_ISSET(i, exceptset))) { - struct lwip_sock *sock = tryget_socket(i); - LWIP_ASSERT("sock != NULL", sock != NULL); + struct lwip_sock *sock; SYS_ARCH_PROTECT(lev); - LWIP_ASSERT("sock->select_waiting > 0", sock->select_waiting > 0); - sock->select_waiting--; + sock = tryget_socket(i); + if (sock != NULL) { + /* @todo: what if this is a new socket (reallocated?) in this case, + select_waiting-- would be wrong (a global 'sockalloc' counter, + stored per socket could help) */ + LWIP_ASSERT("sock->select_waiting > 0", sock->select_waiting > 0); + if (sock->select_waiting > 0) { + sock->select_waiting--; + } + } else { + /* Not a valid socket */ + nready = -1; + } SYS_ARCH_UNPROTECT(lev); } } @@ -1330,6 +1353,12 @@ lwip_select(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset, sys_sem_free(&select_cb.sem); #endif /* LWIP_NETCONN_SEM_PER_THREAD */ + if (nready < 0) { + /* This happens when a socket got closed while waiting */ + set_errno(EBADF); + return -1; + } + if (waitres == SYS_ARCH_TIMEOUT) { /* Timeout */ LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select: timeout expired\n"));