Fix errors during gsn_restart file path composition: - possible buffer overflow because the wrong remaining length was fed to strncat(). - missing path separator: put restart file in dir/gsn_restart instead of ../dirgsn_restart. This assumes that the path separator is '/'. Use talloc_asprintf() to fix all filename length problems and shorten the code. In order to free the allocated path, add a free_filename label, and jump there instead of returning from the fopen("w") failure branch. Also don't return from "fclose failed" branch in order to free the path, remove the if {} braces. Remove the NAMESIZE constant that is now unused. --- gtp/gtp.c | 18 ++++++++---------- gtp/gtp.h | 1 - 2 files changed, 8 insertions(+), 11 deletions(-) diff --git a/gtp/gtp.c b/gtp/gtp.c index 12cb492..161a6f0 100644 --- a/gtp/gtp.c +++ b/gtp/gtp.c @@ -646,13 +646,11 @@ static void log_restart(struct gsn_t *gsn) FILE *f; int i, rc; int counter = 0; - char filename[NAMESIZE]; - - filename[NAMESIZE - 1] = 0; /* No null term. guarantee by strncpy */ - strncpy(filename, gsn->statedir, NAMESIZE - 1); - strncat(filename, RESTART_FILE, NAMESIZE - 1 - sizeof(RESTART_FILE)); - + char *filename; + i = umask(022); + filename = talloc_asprintf(NULL, "%s/%s", gsn->statedir, RESTART_FILE); + OSMO_ASSERT(filename); /* We try to open file. On failure we will later try to create file */ if (!(f = fopen(filename, "r"))) { @@ -680,17 +678,17 @@ static void log_restart(struct gsn_t *gsn) LOGP(DLGTP, LOGL_ERROR, "fopen(path=%s, mode=%s) failed: Error = %s\n", filename, "w", strerror(errno)); - return; + goto free_filename; } umask(i); fprintf(f, "%d\n", gsn->restart_counter); close_file: - if (fclose(f)) { + if (fclose(f)) LOGP(DLGTP, LOGL_ERROR, "fclose failed: Error = %s\n", strerror(errno)); - return; - } +free_filename: + talloc_free(filename); } int gtp_new(struct gsn_t **gsn, char *statedir, struct in_addr *listen, diff --git a/gtp/gtp.h b/gtp/gtp.h index 539e255..1434e1e 100644 --- a/gtp/gtp.h +++ b/gtp/gtp.h @@ -29,7 +29,6 @@ #define ERRMSG_SIZE 255 #define RESTART_FILE "gsn_restart" -#define NAMESIZE 1024 /* GTP version 1 extension header type definitions. */ #define GTP_EXT_PDCP_PDU 0xC0 /* PDCP PDU Number */ -- 2.1.4