From 13776bf7362b14dc3a5abdb19be7d6adafba7326 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Fri, 5 Jun 2020 18:44:14 +0000 Subject: [PATCH] librtld_db: Handle anonymous mappings below the first file mapping. r360979 erroneously assumed that the lowest mapping in an address space would be a file mapping, but of course this is not true in general. Reported and tested by: Frederic Chardon MFC after: 3 days --- lib/librtld_db/rtld_db.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/lib/librtld_db/rtld_db.c b/lib/librtld_db/rtld_db.c index fc4ad8f4834b..9edeecfb95c5 100644 --- a/lib/librtld_db/rtld_db.c +++ b/lib/librtld_db/rtld_db.c @@ -186,11 +186,15 @@ rd_loadobj_iter(rd_agent_t *rdap, rl_iter_f *cb, void *clnt_data) * file, but we want the mapping offset relative to the base * mapping. */ - if (kve->kve_type == KVME_TYPE_VNODE && - kve->kve_vn_fileid != fileid) { - base = kve->kve_start; - fileid = kve->kve_vn_fileid; - path = kve->kve_path; + if (kve->kve_type == KVME_TYPE_VNODE) { + if (kve->kve_vn_fileid != fileid) { + base = kve->kve_start; + fileid = kve->kve_vn_fileid; + path = kve->kve_path; + } + } else { + base = 0; + path = NULL; } memset(&rdl, 0, sizeof(rdl)); /* @@ -205,7 +209,8 @@ rd_loadobj_iter(rd_agent_t *rdap, rl_iter_f *cb, void *clnt_data) rdl.rdl_prot |= RD_RDL_W; if (kve->kve_protection & KVME_PROT_EXEC) rdl.rdl_prot |= RD_RDL_X; - strlcpy(rdl.rdl_path, path, sizeof(rdl.rdl_path)); + if (path != NULL) + strlcpy(rdl.rdl_path, path, sizeof(rdl.rdl_path)); if ((*cb)(&rdl, clnt_data) != 0) { ret = RD_ERR; break;