arch/arc/kernel/unwind.c | 15 ++++------ kernel/module/main.c | 61 +++++++++++----------------------------- 2 files changed, 22 insertions(+), 54 deletions(-)
Three changes here:
1. Shorter variable names in arch/arc/kernel/unwind.c:unwind_add_table, to
make it easier to read.
2. Rewrite free_mod_mem() so it is more obvious that MOD_DATA need to be
freed last.
3. Clean up the use of CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC.
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Song Liu <song@kernel.org>
---
This is the follow up patch on top of [1]. I would recommend fold this
into [1].
[1] https://lore.kernel.org/linux-modules/20230207002802.2514802-1-song@kernel.org/T/#u
---
arch/arc/kernel/unwind.c | 15 ++++------
kernel/module/main.c | 61 +++++++++++-----------------------------
2 files changed, 22 insertions(+), 54 deletions(-)
diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c
index 933451f4494f..9270d0a713c3 100644
--- a/arch/arc/kernel/unwind.c
+++ b/arch/arc/kernel/unwind.c
@@ -369,8 +369,8 @@ void *unwind_add_table(struct module *module, const void *table_start,
unsigned long table_size)
{
struct unwind_table *table;
- struct module_memory *mod_mem_core_text;
- struct module_memory *mod_mem_init_text;
+ struct module_memory *core_text;
+ struct module_memory *init_text;
if (table_size <= 0)
return NULL;
@@ -379,14 +379,11 @@ void *unwind_add_table(struct module *module, const void *table_start,
if (!table)
return NULL;
- mod_mem_core_text = &module->mem[MOD_TEXT];
- mod_mem_init_text = &module->mem[MOD_INIT_TEXT];
+ core_text = &module->mem[MOD_TEXT];
+ init_text = &module->mem[MOD_INIT_TEXT];
- init_unwind_table(table, module->name,
- mod_mem_core_text->base, mod_mem_core_text->size,
- mod_mem_init_text->base, mod_mem_init_text->size,
- table_start, table_size,
- NULL, 0);
+ init_unwind_table(table, module->name, core_text->base, core_text->size,
+ init_text->base, init_text->size, table_start, table_size, NULL, 0);
init_unwind_hdr(table, unw_hdr_alloc);
diff --git a/kernel/module/main.c b/kernel/module/main.c
index c598f11e7016..2724bc1b9a90 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -927,26 +927,17 @@ static ssize_t store_uevent(struct module_attribute *mattr,
struct module_attribute module_uevent =
__ATTR(uevent, 0200, NULL, store_uevent);
-#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
-
-static ssize_t show_coresize(struct module_attribute *mattr,
- struct module_kobject *mk, char *buffer)
-{
- return sprintf(buffer, "%u\n", mk->mod->mem[MOD_TEXT].size);
-}
-
-#else
-
static ssize_t show_coresize(struct module_attribute *mattr,
struct module_kobject *mk, char *buffer)
{
- unsigned int size = 0;
+ unsigned int size = mk->mod->mem[MOD_TEXT].size;
- for_class_mod_mem_type(type, core)
- size += mk->mod->mem[type].size;
+ if (!IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC)) {
+ for_class_mod_mem_type(type, core_data)
+ size += mk->mod->mem[type].size;
+ }
return sprintf(buffer, "%u\n", size);
}
-#endif
static struct module_attribute modinfo_coresize =
__ATTR(coresize, 0444, show_coresize, NULL);
@@ -1170,17 +1161,11 @@ void __weak module_arch_freeing_init(struct module *mod)
{
}
-#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
static bool mod_mem_use_vmalloc(enum mod_mem_type type)
{
- return mod_mem_type_is_core_data(type);
-}
-#else
-static bool mod_mem_use_vmalloc(enum mod_mem_type type)
-{
- return false;
+ return IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC) &&
+ mod_mem_type_is_core_data(type);
}
-#endif
static void *module_memory_alloc(unsigned int size, enum mod_mem_type type)
{
@@ -1199,34 +1184,21 @@ static void module_memory_free(void *ptr, enum mod_mem_type type)
static void free_mod_mem(struct module *mod)
{
- /* free the memory in the right order to avoid use-after-free */
- static enum mod_mem_type mod_mem_free_order[MOD_MEM_NUM_TYPES] = {
- /* first free init sections */
- MOD_INIT_TEXT,
- MOD_INIT_DATA,
- MOD_INIT_RODATA,
-
- /* then core sections, except rw data */
- MOD_TEXT,
- MOD_RODATA,
- MOD_RO_AFTER_INIT,
-
- /* rw data need to be freed last, as it hosts mod */
- MOD_DATA,
- };
- int i;
-
- BUILD_BUG_ON(ARRAY_SIZE(mod_mem_free_order) != MOD_MEM_NUM_TYPES);
-
- for (i = 0; i < MOD_MEM_NUM_TYPES; i++) {
- enum mod_mem_type type = mod_mem_free_order[i];
+ for_each_mod_mem_type(type) {
struct module_memory *mod_mem = &mod->mem[type];
+ if (type == MOD_DATA)
+ continue;
+
/* Free lock-classes; relies on the preceding sync_rcu(). */
lockdep_free_key_range(mod_mem->base, mod_mem->size);
if (mod_mem->size)
module_memory_free(mod_mem->base, type);
}
+
+ /* MOD_DATA hosts mod, so free it at last */
+ lockdep_free_key_range(mod->mem[MOD_DATA].base, mod->mem[MOD_DATA].size);
+ module_memory_free(mod->mem[MOD_DATA].base, MOD_DATA);
}
/* Free a module, remove from lists, etc. */
@@ -2211,8 +2183,7 @@ static int move_module(struct module *mod, struct load_info *info)
if (!(shdr->sh_flags & SHF_ALLOC))
continue;
- dest = mod->mem[type].base +
- (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK);
+ dest = mod->mem[type].base + (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK);
if (shdr->sh_type != SHT_NOBITS)
memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
--
2.30.2
Le 09/02/2023 à 18:56, Song Liu a écrit : > Three changes here: > > 1. Shorter variable names in arch/arc/kernel/unwind.c:unwind_add_table, to > make it easier to read. > 2. Rewrite free_mod_mem() so it is more obvious that MOD_DATA need to be > freed last. > 3. Clean up the use of CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC. > > Cc: Luis Chamberlain <mcgrof@kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Guenter Roeck <linux@roeck-us.net> > Cc: Christophe Leroy <christophe.leroy@csgroup.eu> > Signed-off-by: Song Liu <song@kernel.org> > > --- > > This is the follow up patch on top of [1]. I would recommend fold this > into [1]. With this patch folded into [1], Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> > > [1] https://lore.kernel.org/linux-modules/20230207002802.2514802-1-song@kernel.org/T/#u > --- > arch/arc/kernel/unwind.c | 15 ++++------ > kernel/module/main.c | 61 +++++++++++----------------------------- > 2 files changed, 22 insertions(+), 54 deletions(-) > > diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c > index 933451f4494f..9270d0a713c3 100644 > --- a/arch/arc/kernel/unwind.c > +++ b/arch/arc/kernel/unwind.c > @@ -369,8 +369,8 @@ void *unwind_add_table(struct module *module, const void *table_start, > unsigned long table_size) > { > struct unwind_table *table; > - struct module_memory *mod_mem_core_text; > - struct module_memory *mod_mem_init_text; > + struct module_memory *core_text; > + struct module_memory *init_text; > > if (table_size <= 0) > return NULL; > @@ -379,14 +379,11 @@ void *unwind_add_table(struct module *module, const void *table_start, > if (!table) > return NULL; > > - mod_mem_core_text = &module->mem[MOD_TEXT]; > - mod_mem_init_text = &module->mem[MOD_INIT_TEXT]; > + core_text = &module->mem[MOD_TEXT]; > + init_text = &module->mem[MOD_INIT_TEXT]; > > - init_unwind_table(table, module->name, > - mod_mem_core_text->base, mod_mem_core_text->size, > - mod_mem_init_text->base, mod_mem_init_text->size, > - table_start, table_size, > - NULL, 0); > + init_unwind_table(table, module->name, core_text->base, core_text->size, > + init_text->base, init_text->size, table_start, table_size, NULL, 0); > > init_unwind_hdr(table, unw_hdr_alloc); > > diff --git a/kernel/module/main.c b/kernel/module/main.c > index c598f11e7016..2724bc1b9a90 100644 > --- a/kernel/module/main.c > +++ b/kernel/module/main.c > @@ -927,26 +927,17 @@ static ssize_t store_uevent(struct module_attribute *mattr, > struct module_attribute module_uevent = > __ATTR(uevent, 0200, NULL, store_uevent); > > -#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC > - > -static ssize_t show_coresize(struct module_attribute *mattr, > - struct module_kobject *mk, char *buffer) > -{ > - return sprintf(buffer, "%u\n", mk->mod->mem[MOD_TEXT].size); > -} > - > -#else > - > static ssize_t show_coresize(struct module_attribute *mattr, > struct module_kobject *mk, char *buffer) > { > - unsigned int size = 0; > + unsigned int size = mk->mod->mem[MOD_TEXT].size; > > - for_class_mod_mem_type(type, core) > - size += mk->mod->mem[type].size; > + if (!IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC)) { > + for_class_mod_mem_type(type, core_data) > + size += mk->mod->mem[type].size; > + } > return sprintf(buffer, "%u\n", size); > } > -#endif > > static struct module_attribute modinfo_coresize = > __ATTR(coresize, 0444, show_coresize, NULL); > @@ -1170,17 +1161,11 @@ void __weak module_arch_freeing_init(struct module *mod) > { > } > > -#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC > static bool mod_mem_use_vmalloc(enum mod_mem_type type) > { > - return mod_mem_type_is_core_data(type); > -} > -#else > -static bool mod_mem_use_vmalloc(enum mod_mem_type type) > -{ > - return false; > + return IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC) && > + mod_mem_type_is_core_data(type); > } > -#endif > > static void *module_memory_alloc(unsigned int size, enum mod_mem_type type) > { > @@ -1199,34 +1184,21 @@ static void module_memory_free(void *ptr, enum mod_mem_type type) > > static void free_mod_mem(struct module *mod) > { > - /* free the memory in the right order to avoid use-after-free */ > - static enum mod_mem_type mod_mem_free_order[MOD_MEM_NUM_TYPES] = { > - /* first free init sections */ > - MOD_INIT_TEXT, > - MOD_INIT_DATA, > - MOD_INIT_RODATA, > - > - /* then core sections, except rw data */ > - MOD_TEXT, > - MOD_RODATA, > - MOD_RO_AFTER_INIT, > - > - /* rw data need to be freed last, as it hosts mod */ > - MOD_DATA, > - }; > - int i; > - > - BUILD_BUG_ON(ARRAY_SIZE(mod_mem_free_order) != MOD_MEM_NUM_TYPES); > - > - for (i = 0; i < MOD_MEM_NUM_TYPES; i++) { > - enum mod_mem_type type = mod_mem_free_order[i]; > + for_each_mod_mem_type(type) { > struct module_memory *mod_mem = &mod->mem[type]; > > + if (type == MOD_DATA) > + continue; > + > /* Free lock-classes; relies on the preceding sync_rcu(). */ > lockdep_free_key_range(mod_mem->base, mod_mem->size); > if (mod_mem->size) > module_memory_free(mod_mem->base, type); > } > + > + /* MOD_DATA hosts mod, so free it at last */ > + lockdep_free_key_range(mod->mem[MOD_DATA].base, mod->mem[MOD_DATA].size); > + module_memory_free(mod->mem[MOD_DATA].base, MOD_DATA); > } > > /* Free a module, remove from lists, etc. */ > @@ -2211,8 +2183,7 @@ static int move_module(struct module *mod, struct load_info *info) > if (!(shdr->sh_flags & SHF_ALLOC)) > continue; > > - dest = mod->mem[type].base + > - (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK); > + dest = mod->mem[type].base + (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK); > > if (shdr->sh_type != SHT_NOBITS) > memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
On Thu, Feb 09, 2023 at 07:43:23PM +0000, Christophe Leroy wrote: > > > Le 09/02/2023 à 18:56, Song Liu a écrit : > > Three changes here: > > > > 1. Shorter variable names in arch/arc/kernel/unwind.c:unwind_add_table, to > > make it easier to read. > > 2. Rewrite free_mod_mem() so it is more obvious that MOD_DATA need to be > > freed last. > > 3. Clean up the use of CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC. > > > > Cc: Luis Chamberlain <mcgrof@kernel.org> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > Cc: Peter Zijlstra <peterz@infradead.org> > > Cc: Guenter Roeck <linux@roeck-us.net> > > Cc: Christophe Leroy <christophe.leroy@csgroup.eu> > > Signed-off-by: Song Liu <song@kernel.org> > > > > --- > > > > This is the follow up patch on top of [1]. I would recommend fold this > > into [1]. > > With this patch folded into [1], > > Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> I've squashed this into the last patch from Song and added your Reviewed-by tag, and pushed to modules-next. That'll sit there for a full cycle for testing. Luis
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