The stack frame size could grow too large when the plugin used long long
on 32-bit architectures when the given function had too many basic blocks.
The gcc warning was:
drivers/pci/hotplug/ibmphp_ebda.c: In function 'ibmphp_access_ebda':
drivers/pci/hotplug/ibmphp_ebda.c:409:1: warning: the frame size of 1108 bytes is larger than 1024 bytes [-Wframe-larger-than=]
This switches latent_entropy from u64 to unsigned long.
Thanks to PaX Team and Emese Revfy for the patch.
Signed-off-by: Kees Cook <keescook@chromium.org>
#endif
#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
#endif
#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
-volatile u64 latent_entropy __latent_entropy;
+volatile unsigned long latent_entropy __latent_entropy;
EXPORT_SYMBOL(latent_entropy);
#endif
EXPORT_SYMBOL(latent_entropy);
#endif
- *rhs = build_int_cstu(unsigned_intDI_type_node, random_const);
+ *rhs = build_int_cstu(long_unsigned_type_node, random_const);
enum tree_code op;
/* 1. create temporary copy of latent_entropy */
enum tree_code op;
/* 1. create temporary copy of latent_entropy */
- temp = create_var(unsigned_intDI_type_node, "tmp_latent_entropy");
+ temp = create_var(long_unsigned_type_node, "temp_latent_entropy");
/* 2. read... */
add_referenced_var(latent_entropy_decl);
/* 2. read... */
add_referenced_var(latent_entropy_decl);
gsi_insert_before(&gsi, call, GSI_NEW_STMT);
update_stmt(call);
gsi_insert_before(&gsi, call, GSI_NEW_STMT);
update_stmt(call);
- udi_frame_addr = fold_convert(unsigned_intDI_type_node, frame_addr);
+ udi_frame_addr = fold_convert(long_unsigned_type_node, frame_addr);
assign = gimple_build_assign(local_entropy, udi_frame_addr);
gsi_insert_after(&gsi, assign, GSI_NEW_STMT);
update_stmt(assign);
/* 3. create temporary copy of latent_entropy */
assign = gimple_build_assign(local_entropy, udi_frame_addr);
gsi_insert_after(&gsi, assign, GSI_NEW_STMT);
update_stmt(assign);
/* 3. create temporary copy of latent_entropy */
- tmp = create_var(unsigned_intDI_type_node, "tmp_latent_entropy");
+ tmp = create_var(long_unsigned_type_node, "temp_latent_entropy");
/* 4. read the global entropy variable into local entropy */
add_referenced_var(latent_entropy_decl);
/* 4. read the global entropy variable into local entropy */
add_referenced_var(latent_entropy_decl);
update_stmt(assign);
rand_cst = get_random_const();
update_stmt(assign);
rand_cst = get_random_const();
- rand_const = build_int_cstu(unsigned_intDI_type_node, rand_cst);
+ rand_const = build_int_cstu(long_unsigned_type_node, rand_cst);
op = get_op(NULL);
assign = create_assign(op, local_entropy, local_entropy, rand_const);
gsi_insert_after(&gsi, assign, GSI_NEW_STMT);
op = get_op(NULL);
assign = create_assign(op, local_entropy, local_entropy, rand_const);
gsi_insert_after(&gsi, assign, GSI_NEW_STMT);
}
/* 1. create the local entropy variable */
}
/* 1. create the local entropy variable */
- local_entropy = create_var(unsigned_intDI_type_node, "local_entropy");
+ local_entropy = create_var(long_unsigned_type_node, "local_entropy");
/* 2. initialize the local entropy variable */
init_local_entropy(bb, local_entropy);
/* 2. initialize the local entropy variable */
init_local_entropy(bb, local_entropy);
- /* extern volatile u64 latent_entropy */
- gcc_assert(TYPE_PRECISION(long_long_unsigned_type_node) == 64);
- quals = TYPE_QUALS(long_long_unsigned_type_node) | TYPE_QUAL_VOLATILE;
- type = build_qualified_type(long_long_unsigned_type_node, quals);
+ /* extern volatile unsigned long latent_entropy */
+ quals = TYPE_QUALS(long_unsigned_type_node) | TYPE_QUAL_VOLATILE;
+ type = build_qualified_type(long_unsigned_type_node, quals);
id = get_identifier("latent_entropy");
latent_entropy_decl = build_decl(UNKNOWN_LOCATION, VAR_DECL, id, type);
id = get_identifier("latent_entropy");
latent_entropy_decl = build_decl(UNKNOWN_LOCATION, VAR_DECL, id, type);