This is a note to let you know that I've just added the patch titled
MIPS: BPF: Fix multiple problems in JIT skb access helpers.
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mips-bpf-fix-multiple-problems-in-jit-skb-access-helpers.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon Mar 19 09:58:12 CET 2018
From: David Daney <david.daney@xxxxxxxxxx>
Date: Tue, 14 Mar 2017 14:21:44 -0700
Subject: MIPS: BPF: Fix multiple problems in JIT skb access helpers.
From: David Daney <david.daney@xxxxxxxxxx>
[ Upstream commit a81507c79f4ae9a0f9fb1054b59b62a090620dd9 ]
o Socket data is unsigned, so use unsigned accessors instructions.
o Fix path result pointer generation arithmetic.
o Fix half-word byte swapping code for unsigned semantics.
Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
Cc: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Steven J. Hill <steven.hill@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: netdev@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Patchwork: https://patchwork.linux-mips.org/patch/15747/
Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/mips/net/bpf_jit_asm.S | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
--- a/arch/mips/net/bpf_jit_asm.S
+++ b/arch/mips/net/bpf_jit_asm.S
@@ -90,18 +90,14 @@ FEXPORT(sk_load_half_positive)
is_offset_in_header(2, half)
/* Offset within header boundaries */
PTR_ADDU t1, $r_skb_data, offset
- .set reorder
- lh $r_A, 0(t1)
- .set noreorder
+ lhu $r_A, 0(t1)
#ifdef CONFIG_CPU_LITTLE_ENDIAN
# if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
- wsbh t0, $r_A
- seh $r_A, t0
+ wsbh $r_A, $r_A
# else
- sll t0, $r_A, 24
- andi t1, $r_A, 0xff00
- sra t0, t0, 16
- srl t1, t1, 8
+ sll t0, $r_A, 8
+ srl t1, $r_A, 8
+ andi t0, t0, 0xff00
or $r_A, t0, t1
# endif
#endif
@@ -115,7 +111,7 @@ FEXPORT(sk_load_byte_positive)
is_offset_in_header(1, byte)
/* Offset within header boundaries */
PTR_ADDU t1, $r_skb_data, offset
- lb $r_A, 0(t1)
+ lbu $r_A, 0(t1)
jr $r_ra
move $r_ret, zero
END(sk_load_byte)
@@ -139,6 +135,11 @@ FEXPORT(sk_load_byte_positive)
* (void *to) is returned in r_s0
*
*/
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+#define DS_OFFSET(SIZE) (4 * SZREG)
+#else
+#define DS_OFFSET(SIZE) ((4 * SZREG) + (4 - SIZE))
+#endif
#define bpf_slow_path_common(SIZE) \
/* Quick check. Are we within reasonable boundaries? */ \
LONG_ADDIU $r_s1, $r_skb_len, -SIZE; \
@@ -150,7 +151,7 @@ FEXPORT(sk_load_byte_positive)
PTR_LA t0, skb_copy_bits; \
PTR_S $r_ra, (5 * SZREG)($r_sp); \
/* Assign low slot to a2 */ \
- move a2, $r_sp; \
+ PTR_ADDIU a2, $r_sp, DS_OFFSET(SIZE); \
jalr t0; \
/* Reset our destination slot (DS but it's ok) */ \
INT_S zero, (4 * SZREG)($r_sp); \
Patches currently in stable-queue which might be from david.daney@xxxxxxxxxx are
queue-4.4/mips-bpf-quit-clobbering-callee-saved-registers-in-jit-code.patch
queue-4.4/mips-bpf-fix-multiple-problems-in-jit-skb-access-helpers.patch