After commit de7d2b567d040e3b67fe7121945982f14343213d (mm/vmalloc.c: report
more vmalloc failures) users will get a warning if vmalloc_node_range() is
called with size 0. This happens if module's init size equals to 0. This
patch changes ARM, MIPS and x86 module_alloc() to return NULL before calling
vmalloc_node_range() that would also return NULL and print a warning.
Signed-off-by: Veli-Pekka Peltola <veli-pekka.peltola@xxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: x86@xxxxxxxxxx
---
I found this with ARM but after checking out various implementations of
module_alloc() I thought it would be better to fix all at once.
One way to replicate the warning:
compile kernel with CONFIG_KALLSYMS=n
insmod module without init, I used usb-common.ko
arch/arm/kernel/module.c | 4 ++--
arch/mips/kernel/module.c | 4 ++--
arch/x86/kernel/module.c | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index 1e9be5d..d44d212 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -39,8 +39,8 @@
#ifdef CONFIG_MMU
void *module_alloc(unsigned long size)
{
- return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
- GFP_KERNEL, PAGE_KERNEL_EXEC, -1,
+ return size == 0 ? NULL : __vmalloc_node_range(size, 1, MODULES_VADDR,
+ MODULES_END, GFP_KERNEL, PAGE_KERNEL_EXEC, -1,
__builtin_return_address(0));
}
#endif
diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c
index a5066b1..cd768e9 100644
--- a/arch/mips/kernel/module.c
+++ b/arch/mips/kernel/module.c
@@ -47,8 +47,8 @@ static DEFINE_SPINLOCK(dbe_lock);
#ifdef MODULE_START
void *module_alloc(unsigned long size)
{
- return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
- GFP_KERNEL, PAGE_KERNEL, -1,
+ return size == 0 ? NULL : __vmalloc_node_range(size, 1, MODULE_START,
+ MODULE_END, GFP_KERNEL, PAGE_KERNEL, -1,
__builtin_return_address(0));
}
#endif
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 925179f..bff6118 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -38,7 +38,7 @@
void *module_alloc(unsigned long size)
{
- if (PAGE_ALIGN(size) > MODULES_LEN)
+ if (size == 0 || PAGE_ALIGN(size) > MODULES_LEN)
return NULL;
return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC,
--
1.7.5.4
