When loading an invalid module which uses a declaration ID 0, semodule_package crashes in policydb_index_decls(): p->decl_val_to_struct[decl->decl_id - 1] = decl; gdb shows the following stack trace: #0 0x00007ffff7aa1bbd in policydb_index_decls (p=p@entry=0x605360) at policydb.c:1034 #1 0x00007ffff7aaa9fc in policydb_read (p=<optimized out>, fp=fp@entry=0x605090, verbose=verbose@entry=0) at policydb.c:3958 #2 0x00007ffff7ab4764 in sepol_policydb_read (p=<optimized out>, pf=pf@entry=0x605090) at policydb_public.c:174 #3 0x0000000000401d33 in main (argc=<optimized out>, argv=0x7fffffffdc88) at semodule_package.c:220 Change policydb_index_decls() to report an error instead: libsepol.policydb_index_decls: invalid decl ID 0 Signed-off-by: Nicolas Iooss <nicolas.iooss@xxxxxxx> --- libsepol/src/policydb.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/libsepol/src/policydb.c b/libsepol/src/policydb.c index f9b2ec379c33..38c38f42cd2d 100644 --- a/libsepol/src/policydb.c +++ b/libsepol/src/policydb.c @@ -1011,7 +1011,7 @@ int policydb_index_decls(policydb_t * p) { avrule_block_t *curblock; avrule_decl_t *decl; - int num_decls = 0; + unsigned int num_decls = 0; free(p->decl_val_to_struct); @@ -1031,6 +1031,10 @@ int policydb_index_decls(policydb_t * p) for (curblock = p->global; curblock != NULL; curblock = curblock->next) { for (decl = curblock->branch_list; decl != NULL; decl = decl->next) { + if (decl->decl_id < 1 || decl->decl_id > num_decls) { + ERR(NULL, "invalid decl ID %u", decl->decl_id); + return -1; + } p->decl_val_to_struct[decl->decl_id - 1] = decl; } } -- 2.10.2 _______________________________________________ Selinux mailing list Selinux@xxxxxxxxxxxxx To unsubscribe, send email to Selinux-leave@xxxxxxxxxxxxx. To get help, send an email containing "help" to Selinux-request@xxxxxxxxxxxxx.