From FEDORA_PATCHES Mon Sep 17 00:00:00 2001 From: Fedora GDB patches Date: Fri, 27 Oct 2017 21:07:50 +0200 Subject: Add a check to ensure that a type may fit into host memory FileName: gdb-rhbz795424-bitpos-21of25.patch ;; Fix `GDB cannot access struct member whose offset is larger than 256MB' ;; (RH BZ 795424). ;;=push http://sourceware.org/ml/gdb-patches/2012-09/msg00632.html --MP_/PnL6l3LUsXWpZ/olqawWlzb Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Disposition: inline Hi, This is part two of the bitpos expansion patch. This implements checks in some places in the code to ensure that a type size in ULONGEST is small enough to fit into host memory. Tested for regressions on x86_64 Fedora 16. Regards, Siddhesh --MP_/PnL6l3LUsXWpZ/olqawWlzb Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Content-Disposition: attachment; filename=ChangeLog-ensure_sizet gdb/ChangeLog * alpha-tdep.c (alpha_push_dummy_call) Check for underflow in SP. * cp-valprint (cp_print_value): Ensure BASECLASS fits into size_t. * dwarf2loc.c (read_pieced_value): Ensure that THIS_SIZE fits into size_t. (write_pieced_value): Likewise. * findcmd.c (parse_find_args): Ensure PATTERN_BUF_SIZE fits into size_t. * p-valprint (pascal_object_print_value): Ensure BASECLASS fits into size_t. * utils.c (ulongest_fits_host_or_error): New function to find if a ULONGEST number fits into size_t. * utils.h: Declare ulongest_fits_host_or_error. * valops.c (search_struct_method): Ensure BASECLASS fits into size_t. * value.c (allocate_value_lazy): Ensure TYPE fits into size_t. (allocate_value_contents): Likewise. (set_value_enclosing_type): Ensure NEW_ENCL_TYPE fits into size_t. * vax-tdep.c (vax_return_value): Ensure that TYPE fits into size_t. --MP_/PnL6l3LUsXWpZ/olqawWlzb Content-Type: text/x-patch Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=bitpos-ensure-size_t.patch diff --git a/gdb/alpha-tdep.c b/gdb/alpha-tdep.c index 78422faa6c..9b749559a1 100644 --- a/gdb/alpha-tdep.c +++ b/gdb/alpha-tdep.c @@ -413,6 +413,13 @@ alpha_push_dummy_call (struct gdbarch *gdbarch, struct value *function, accumulate_size = 0; else accumulate_size -= sizeof(arg_reg_buffer); + + /* Check for underflow. */ + if (sp - accumulate_size > sp) + error (_("Insufficient memory in GDB host for arguments, " + "need %s bytes, but less than %s bytes available."), + plongest (accumulate_size), plongest (CORE_ADDR_MAX - sp)); + sp -= accumulate_size; /* Keep sp aligned to a multiple of 16 as the ABI requires. */ diff --git a/gdb/cp-valprint.c b/gdb/cp-valprint.c index 25f1512857..823ac8fbd6 100644 --- a/gdb/cp-valprint.c +++ b/gdb/cp-valprint.c @@ -529,6 +529,7 @@ cp_print_value (struct type *type, struct type *real_type, if ((boffset + offset) < 0 || (boffset + offset) >= TYPE_LENGTH (real_type)) { + ulongest_fits_host_or_error (TYPE_LENGTH (baseclass)); gdb::byte_vector buf (TYPE_LENGTH (baseclass)); if (target_read_memory (address + boffset, buf.data (), diff --git a/gdb/defs.h b/gdb/defs.h index dc38a288c5..ce5fee3ba3 100644 --- a/gdb/defs.h +++ b/gdb/defs.h @@ -674,4 +674,6 @@ DEF_ENUM_FLAGS_TYPE (enum user_selected_what_flag, user_selected_what); #include "utils.h" +extern void ulongest_fits_host_or_error (ULONGEST num); + #endif /* #ifndef DEFS_H */ diff --git a/gdb/p-valprint.c b/gdb/p-valprint.c index e5c1b07040..06fb3b77c9 100644 --- a/gdb/p-valprint.c +++ b/gdb/p-valprint.c @@ -773,6 +773,7 @@ pascal_object_print_value (struct type *type, const gdb_byte *valaddr, if (boffset < 0 || boffset >= TYPE_LENGTH (type)) { + ulongest_fits_host_or_error (TYPE_LENGTH (baseclass)); buf.resize (TYPE_LENGTH (baseclass)); base_valaddr = buf.data (); diff --git a/gdb/utils.c b/gdb/utils.c index c69c01efc1..42d4225595 100644 --- a/gdb/utils.c +++ b/gdb/utils.c @@ -2816,6 +2816,17 @@ string_to_core_addr (const char *my_string) return addr; } +/* Ensure that the input NUM is not larger than the maximum capacity of the + host system. We choose SIZE_MAX / 8 as a conservative estimate of the size + of a resource that a system may allocate. */ +void +ulongest_fits_host_or_error (ULONGEST num) +{ + if (num > SIZE_MAX / 8) + error (_("Insufficient memory in host GDB for object of size %s bytes, " + "maximum allowed %s bytes."), pulongest (num), + pulongest (SIZE_MAX / 8)); +} #if GDB_SELF_TEST static void diff --git a/gdb/valops.c b/gdb/valops.c index 96b922dbef..a7f9be5f4e 100644 --- a/gdb/valops.c +++ b/gdb/valops.c @@ -2088,6 +2088,7 @@ search_struct_method (const char *name, struct value **arg1p, { CORE_ADDR address; + ulongest_fits_host_or_error (TYPE_LENGTH (baseclass)); gdb::byte_vector tmp (TYPE_LENGTH (baseclass)); address = value_address (*arg1p); diff --git a/gdb/value.c b/gdb/value.c index 33c28f2340..f1a98a8556 100644 --- a/gdb/value.c +++ b/gdb/value.c @@ -933,6 +933,7 @@ allocate_value_lazy (struct type *type) description correctly. */ check_typedef (type); + ulongest_fits_host_or_error (TYPE_LENGTH (type)); val = new struct value (type); /* Values start out on the all_values chain. */ @@ -1015,6 +1016,8 @@ check_type_length_before_alloc (const struct type *type) static void allocate_value_contents (struct value *val) { + ulongest_fits_host_or_error (TYPE_LENGTH (val->enclosing_type)); + if (!val->contents) { check_type_length_before_alloc (val->enclosing_type); @@ -2876,6 +2879,7 @@ set_value_enclosing_type (struct value *val, struct type *new_encl_type) if (TYPE_LENGTH (new_encl_type) > TYPE_LENGTH (value_enclosing_type (val))) { check_type_length_before_alloc (new_encl_type); + ulongest_fits_host_or_error (TYPE_LENGTH (new_encl_type)); val->contents .reset ((gdb_byte *) xrealloc (val->contents.release (), TYPE_LENGTH (new_encl_type))); diff --git a/gdb/vax-tdep.c b/gdb/vax-tdep.c index 4c1ab2e73e..bd69fd2f48 100644 --- a/gdb/vax-tdep.c +++ b/gdb/vax-tdep.c @@ -218,6 +218,7 @@ vax_return_value (struct gdbarch *gdbarch, struct value *function, ULONGEST addr; regcache_raw_read_unsigned (regcache, VAX_R0_REGNUM, &addr); + ulongest_fits_host_or_error (TYPE_LENGTH (type)); read_memory (addr, readbuf, len); }