From: David Daney <[email protected]>
As reported:
This problem was discovered when doing BGP traffic with the TCP MD5 option
activated, where the following call chain caused a crash:
* tcp_v4_rcv
* tcp_v4_timewait_ack
* tcp_v4_send_ack -> follow stack variable rep.th
* tcp_v4_md5_hash_hdr
* tcp_md5_hash_header
* sg_init_one
* sg_set_buf
* virt_to_page
I noticed that tcp_v4_send_reset uses a similar stack variable and
also calls tcp_v4_md5_hash_hdr, so it has the same problem.
The networking core can indirectly call virt_to_phys() on stack
addresses, if this is done from PID 0, the stack will usually be in
CKSEG0, so virt_to_phys() needs to work there as well
Signed-off-by: David Daney <[email protected]>
---
Not tested against kernel.org kernel, but it may still apply
This could also fix problems noted by Eunbong Song with the
free_initmem_default() call.
arch/mips/include/asm/io.h | 2 +-
arch/mips/include/asm/page.h | 5 +++--
2 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h
index a58f229..37fa957 100644
--- a/arch/mips/include/asm/io.h
+++ b/arch/mips/include/asm/io.h
@@ -116,7 +116,7 @@ static inline void set_io_port_base(unsigned long base)
*/
static inline unsigned long virt_to_phys(volatile const void *address)
{
- return (unsigned long)address - PAGE_OFFSET + PHYS_OFFSET;
+ return __pa(address);
}
/*
diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
index cee3893..e09bff9 100644
--- a/arch/mips/include/asm/page.h
+++ b/arch/mips/include/asm/page.h
@@ -48,7 +48,6 @@
#ifndef __ASSEMBLY__
#include <linux/pfn.h>
-#include <asm/io.h>
extern void build_clear_page(void);
extern void build_copy_page(void);
@@ -139,7 +138,6 @@ typedef struct { unsigned long pgprot; } pgprot_t;
*/
#define ptep_buddy(x) ((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
-#endif /* !__ASSEMBLY__ */
/*
* __pa()/__va() should be used only during mem init.
@@ -156,6 +154,9 @@ typedef struct { unsigned long pgprot; } pgprot_t;
#endif
#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
+#include <asm/io.h>
+#endif /* !__ASSEMBLY__ */
+
/*
* RELOC_HIDE was originally added by 6007b903dfe5f1d13e0c711ac2894bdd4a61b1ad
* (lmo) rsp. 8431fd094d625b94d364fe393076ccef88e6ce18 (kernel.org). The
--
1.7.11.7
It doesn't apply anymore. It was against v3.4.
I will send one against Linus' tree soon.
David Daney
On 05/07/2013 10:23 AM, David Daney wrote:
> From: David Daney <[email protected]>
>
> As reported:
> This problem was discovered when doing BGP traffic with the TCP MD5 option
> activated, where the following call chain caused a crash:
>
> * tcp_v4_rcv
> * tcp_v4_timewait_ack
> * tcp_v4_send_ack -> follow stack variable rep.th
> * tcp_v4_md5_hash_hdr
> * tcp_md5_hash_header
> * sg_init_one
> * sg_set_buf
> * virt_to_page
>
> I noticed that tcp_v4_send_reset uses a similar stack variable and
> also calls tcp_v4_md5_hash_hdr, so it has the same problem.
>
> The networking core can indirectly call virt_to_phys() on stack
> addresses, if this is done from PID 0, the stack will usually be in
> CKSEG0, so virt_to_phys() needs to work there as well
>
> Signed-off-by: David Daney <[email protected]>
> ---
>
> Not tested against kernel.org kernel, but it may still apply
>
> This could also fix problems noted by Eunbong Song with the
> free_initmem_default() call.
>
> arch/mips/include/asm/io.h | 2 +-
> arch/mips/include/asm/page.h | 5 +++--
> 2 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h
> index a58f229..37fa957 100644
> --- a/arch/mips/include/asm/io.h
> +++ b/arch/mips/include/asm/io.h
> @@ -116,7 +116,7 @@ static inline void set_io_port_base(unsigned long base)
> */
> static inline unsigned long virt_to_phys(volatile const void *address)
> {
> - return (unsigned long)address - PAGE_OFFSET + PHYS_OFFSET;
> + return __pa(address);
> }
>
> /*
> diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
> index cee3893..e09bff9 100644
> --- a/arch/mips/include/asm/page.h
> +++ b/arch/mips/include/asm/page.h
> @@ -48,7 +48,6 @@
> #ifndef __ASSEMBLY__
>
> #include <linux/pfn.h>
> -#include <asm/io.h>
>
> extern void build_clear_page(void);
> extern void build_copy_page(void);
> @@ -139,7 +138,6 @@ typedef struct { unsigned long pgprot; } pgprot_t;
> */
> #define ptep_buddy(x) ((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
>
> -#endif /* !__ASSEMBLY__ */
>
> /*
> * __pa()/__va() should be used only during mem init.
> @@ -156,6 +154,9 @@ typedef struct { unsigned long pgprot; } pgprot_t;
> #endif
> #define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
>
> +#include <asm/io.h>
> +#endif /* !__ASSEMBLY__ */
> +
> /*
> * RELOC_HIDE was originally added by 6007b903dfe5f1d13e0c711ac2894bdd4a61b1ad
> * (lmo) rsp. 8431fd094d625b94d364fe393076ccef88e6ce18 (kernel.org). The
>