[PATCH 8/8] initramfs: poison freed initrd memory

From: Christoph Hellwig
Date: Wed Feb 13 2019 - 12:47:04 EST


Various architectures including x86 poison the freed initrd memory.
Do the same in the generic free_initrd_mem implementation and switch
a few more architectures that are identical to the generic code over
to it now.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/mips/mm/init.c | 8 --------
arch/s390/mm/init.c | 8 --------
arch/sparc/mm/init_32.c | 8 --------
arch/sparc/mm/init_64.c | 8 --------
init/initramfs.c | 3 ++-
5 files changed, 2 insertions(+), 33 deletions(-)

diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index b521d8e2d359..a9a977d75838 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -492,14 +492,6 @@ void free_init_pages(const char *what, unsigned long begin, unsigned long end)
printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
}

-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
- free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
- "initrd");
-}
-#endif
-
void (*free_init_pages_eva)(void *begin, void *end) = NULL;

void __ref free_initmem(void)
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 3e82f66d5c61..25e3113091ea 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -154,14 +154,6 @@ void free_initmem(void)
free_initmem_default(POISON_FREE_INITMEM);
}

-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
- free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
- "initrd");
-}
-#endif
-
unsigned long memory_block_size_bytes(void)
{
/*
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index d900952bfc5f..f0dbc0bde70f 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -299,14 +299,6 @@ void free_initmem (void)
free_initmem_default(POISON_FREE_INITMEM);
}

-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
- free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
- "initrd");
-}
-#endif
-
void sparc_flush_page_to_ram(struct page *page)
{
unsigned long vaddr = (unsigned long)page_address(page);
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index b4221d3727d0..4179f0e11fd5 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2602,14 +2602,6 @@ void free_initmem(void)
}
}

-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
- free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
- "initrd");
-}
-#endif
-
pgprot_t PAGE_KERNEL __read_mostly;
EXPORT_SYMBOL(PAGE_KERNEL);

diff --git a/init/initramfs.c b/init/initramfs.c
index f3aaa58ac63d..4a42ff3a2bd1 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -529,7 +529,8 @@ extern unsigned long __initramfs_size;

void __weak free_initrd_mem(unsigned long start, unsigned long end)
{
- free_reserved_area((void *)start, (void *)end, -1, "initrd");
+ free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
+ "initrd");
}

#ifdef CONFIG_KEXEC_CORE
--
2.20.1