From: He Fengqing hefengqing@huawei.com
hulk inclusion category: bugfix bugzilla: NA CVE: CVE-2021-3444
-------------------------------------------------
This reverts commit 62684a24cd00250d44605b9aded87b13d3b5ec68.
Signed-off-by: He Fengqing hefengqing@huawei.com Reviewed-by: Kuohai Xu xukuohai@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- Documentation/networking/filter.txt | 15 +++++++-------- include/uapi/linux/bpf.h | 1 - tools/include/uapi/linux/bpf.h | 1 - 3 files changed, 7 insertions(+), 10 deletions(-)
diff --git a/Documentation/networking/filter.txt b/Documentation/networking/filter.txt index a6caadf243725..e6b4ebb2b2438 100644 --- a/Documentation/networking/filter.txt +++ b/Documentation/networking/filter.txt @@ -863,7 +863,7 @@ Three LSB bits store instruction class which is one of: BPF_STX 0x03 BPF_STX 0x03 BPF_ALU 0x04 BPF_ALU 0x04 BPF_JMP 0x05 BPF_JMP 0x05 - BPF_RET 0x06 BPF_JMP32 0x06 + BPF_RET 0x06 [ class 6 unused, for future if needed ] BPF_MISC 0x07 BPF_ALU64 0x07
When BPF_CLASS(code) == BPF_ALU or BPF_JMP, 4th bit encodes source operand ... @@ -900,9 +900,9 @@ If BPF_CLASS(code) == BPF_ALU or BPF_ALU64 [ in eBPF ], BPF_OP(code) is one of: BPF_ARSH 0xc0 /* eBPF only: sign extending shift right */ BPF_END 0xd0 /* eBPF only: endianness conversion */
-If BPF_CLASS(code) == BPF_JMP or BPF_JMP32 [ in eBPF ], BPF_OP(code) is one of: +If BPF_CLASS(code) == BPF_JMP, BPF_OP(code) is one of:
- BPF_JA 0x00 /* BPF_JMP only */ + BPF_JA 0x00 BPF_JEQ 0x10 BPF_JGT 0x20 BPF_JGE 0x30 @@ -910,8 +910,8 @@ If BPF_CLASS(code) == BPF_JMP or BPF_JMP32 [ in eBPF ], BPF_OP(code) is one of: BPF_JNE 0x50 /* eBPF only: jump != */ BPF_JSGT 0x60 /* eBPF only: signed '>' */ BPF_JSGE 0x70 /* eBPF only: signed '>=' */ - BPF_CALL 0x80 /* eBPF BPF_JMP only: function call */ - BPF_EXIT 0x90 /* eBPF BPF_JMP only: function return */ + BPF_CALL 0x80 /* eBPF only: function call */ + BPF_EXIT 0x90 /* eBPF only: function return */ BPF_JLT 0xa0 /* eBPF only: unsigned '<' */ BPF_JLE 0xb0 /* eBPF only: unsigned '<=' */ BPF_JSLT 0xc0 /* eBPF only: signed '<' */ @@ -934,9 +934,8 @@ Classic BPF wastes the whole BPF_RET class to represent a single 'ret' operation. Classic BPF_RET | BPF_K means copy imm32 into return register and perform function exit. eBPF is modeled to match CPU, so BPF_JMP | BPF_EXIT in eBPF means function exit only. The eBPF program needs to store return -value into register R0 before doing a BPF_EXIT. Class 6 in eBPF is used as -BPF_JMP32 to mean exactly the same operations as BPF_JMP, but with 32-bit wide -operands for the comparisons instead. +value into register R0 before doing a BPF_EXIT. Class 6 in eBPF is currently +unused and reserved for future use.
For load and store instructions the 8-bit 'code' field is divided as:
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index b11a42eb56e97..9a347aefbb40a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -14,7 +14,6 @@ /* Extended instruction set based on top of classic BPF */
/* instruction classes */ -#define BPF_JMP32 0x06 /* jmp mode in word width */ #define BPF_ALU64 0x07 /* alu mode in double word width */
/* ld/ldx fields */ diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 45b08d90cd674..58454e7693f43 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -14,7 +14,6 @@ /* Extended instruction set based on top of classic BPF */
/* instruction classes */ -#define BPF_JMP32 0x06 /* jmp mode in word width */ #define BPF_ALU64 0x07 /* alu mode in double word width */
/* ld/ldx fields */