This is a note to let you know that I've just added the patch titled s390/bpf: fix recache skb->data/hlen for skb_vlan_push/pop to the 4.6-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: s390-bpf-fix-recache-skb-data-hlen-for-skb_vlan_push-pop.patch and it can be found in the queue-4.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 6edf0aa4f8bbdfbb4d6d786892fa02728d05dc36 Mon Sep 17 00:00:00 2001 From: Michael Holzheu <holzheu@xxxxxxxxxxxxxxxxxx> Date: Wed, 11 May 2016 21:13:13 +0200 Subject: s390/bpf: fix recache skb->data/hlen for skb_vlan_push/pop From: Michael Holzheu <holzheu@xxxxxxxxxxxxxxxxxx> commit 6edf0aa4f8bbdfbb4d6d786892fa02728d05dc36 upstream. In case of usage of skb_vlan_push/pop, in the prologue we store the SKB pointer on the stack and restore it after BPF_JMP_CALL to skb_vlan_push/pop. Unfortunately currently there are two bugs in the code: 1) The wrong stack slot (offset 170 instead of 176) is used 2) The wrong register (W1 instead of B1) is saved So fix this and use correct stack slot and register. Fixes: 9db7f2b81880 ("s390/bpf: recache skb->data/hlen for skb_vlan_push/pop") Signed-off-by: Michael Holzheu <holzheu@xxxxxxxxxxxxxxxxxx> Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/net/bpf_jit.h | 4 ++-- arch/s390/net/bpf_jit_comp.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) --- a/arch/s390/net/bpf_jit.h +++ b/arch/s390/net/bpf_jit.h @@ -37,7 +37,7 @@ extern u8 sk_load_word[], sk_load_half[] * | | | * +---------------+ | * | 8 byte skbp | | - * R15+170 -> +---------------+ | + * R15+176 -> +---------------+ | * | 8 byte hlen | | * R15+168 -> +---------------+ | * | 4 byte align | | @@ -58,7 +58,7 @@ extern u8 sk_load_word[], sk_load_half[] #define STK_OFF (STK_SPACE - STK_160_UNUSED) #define STK_OFF_TMP 160 /* Offset of tmp buffer on stack */ #define STK_OFF_HLEN 168 /* Offset of SKB header length on stack */ -#define STK_OFF_SKBP 170 /* Offset of SKB pointer on stack */ +#define STK_OFF_SKBP 176 /* Offset of SKB pointer on stack */ #define STK_OFF_R6 (160 - 11 * 8) /* Offset of r6 on stack */ #define STK_OFF_TCCNT (160 - 12 * 8) /* Offset of tail_call_cnt on stack */ --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -446,7 +446,7 @@ static void bpf_jit_prologue(struct bpf_ emit_load_skb_data_hlen(jit); if (jit->seen & SEEN_SKB_CHANGE) /* stg %b1,ST_OFF_SKBP(%r0,%r15) */ - EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0, REG_15, + EMIT6_DISP_LH(0xe3000000, 0x0024, BPF_REG_1, REG_0, REG_15, STK_OFF_SKBP); } Patches currently in stable-queue which might be from holzheu@xxxxxxxxxxxxxxxxxx are queue-4.6/s390-bpf-fix-recache-skb-data-hlen-for-skb_vlan_push-pop.patch queue-4.6/s390-bpf-reduce-maximum-program-size-to-64-kb.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html