From e5e35e754c28724d5c619f2ec805fd221f8d59ce Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Mon, 8 Mar 2021 15:59:18 +0100 Subject: bpf: BPF-helper for MTU checking add length input The FIB lookup example[1] show how the IP-header field tot_len (iph->tot_len) is used as input to perform the MTU check. This patch extend the BPF-helper bpf_check_mtu() with the same ability to provide the length as user parameter input, via mtu_len parameter. This still needs to be done before the bpf_check_mtu() helper API becomes frozen. [1] samples/bpf/xdp_fwd_kern.c Fixes: 34b2021cc616 ("bpf: Add BPF-helper for MTU checking") Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/161521555850.3515614.6533850861569774444.stgit@firesoul --- include/uapi/linux/bpf.h | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 79c893310492..4ba4ef0ff63a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3850,7 +3850,7 @@ union bpf_attr { * * long bpf_check_mtu(void *ctx, u32 ifindex, u32 *mtu_len, s32 len_diff, u64 flags) * Description - * Check ctx packet size against exceeding MTU of net device (based + * Check packet size against exceeding MTU of net device (based * on *ifindex*). This helper will likely be used in combination * with helpers that adjust/change the packet size. * @@ -3867,6 +3867,14 @@ union bpf_attr { * against the current net device. This is practical if this isn't * used prior to redirect. * + * On input *mtu_len* must be a valid pointer, else verifier will + * reject BPF program. If the value *mtu_len* is initialized to + * zero then the ctx packet size is use. When value *mtu_len* is + * provided as input this specify the L3 length that the MTU check + * is done against. Remember XDP and TC length operate at L2, but + * this value is L3 as this correlate to MTU and IP-header tot_len + * values which are L3 (similar behavior as bpf_fib_lookup). + * * The Linux kernel route table can configure MTUs on a more * specific per route level, which is not provided by this helper. * For route level MTU checks use the **bpf_fib_lookup**\ () @@ -3891,11 +3899,9 @@ union bpf_attr { * * On return *mtu_len* pointer contains the MTU value of the net * device. Remember the net device configured MTU is the L3 size, - * which is returned here and XDP and TX length operate at L2. + * which is returned here and XDP and TC length operate at L2. * Helper take this into account for you, but remember when using - * MTU value in your BPF-code. On input *mtu_len* must be a valid - * pointer and be initialized (to zero), else verifier will reject - * BPF program. + * MTU value in your BPF-code. * * Return * * 0 on success, and populate MTU value in *mtu_len* pointer. -- cgit v1.2.3 From f8425c9396639cc462bcce44b1051f8b4e62fddb Mon Sep 17 00:00:00 2001 From: Alessio Balsini Date: Mon, 25 Jan 2021 15:30:51 +0000 Subject: fuse: 32-bit user space ioctl compat for fuse device With a 64-bit kernel build the FUSE device cannot handle ioctl requests coming from 32-bit user space. This is due to the ioctl command translation that generates different command identifiers that thus cannot be used for direct comparisons without proper manipulation. Explicitly extract type and number from the ioctl command to enable 32-bit user space compatibility on 64-bit kernel builds. Signed-off-by: Alessio Balsini Signed-off-by: Miklos Szeredi --- include/uapi/linux/fuse.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/uapi') diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 98ca64d1beb6..54442612c48b 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -903,7 +903,8 @@ struct fuse_notify_retrieve_in { }; /* Device ioctls: */ -#define FUSE_DEV_IOC_CLONE _IOR(229, 0, uint32_t) +#define FUSE_DEV_IOC_MAGIC 229 +#define FUSE_DEV_IOC_CLONE _IOR(FUSE_DEV_IOC_MAGIC, 0, uint32_t) struct fuse_lseek_in { uint64_t fh; -- cgit v1.2.3 From e43accba9b071dcd106b5e7643b1b106a158cbb1 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Wed, 24 Mar 2021 21:43:32 +0200 Subject: psample: Fix user API breakage Cited commit added a new attribute before the existing group reference count attribute, thereby changing its value and breaking existing applications on new kernels. Before: # psample -l libpsample ERROR psample_group_foreach: failed to recv message: Operation not supported After: # psample -l Group Num Refcount Group Seq 1 1 0 Fix by restoring the value of the old attribute and remove the misleading comments from the enumerator to avoid future bugs. Cc: stable@vger.kernel.org Fixes: d8bed686ab96 ("net: psample: Add tunnel support") Signed-off-by: Ido Schimmel Reported-by: Adiel Bidani Reviewed-by: Jiri Pirko Reviewed-by: Petr Machata Signed-off-by: David S. Miller --- include/uapi/linux/psample.h | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'include/uapi') diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h index aea26ab1431c..bff5032c98df 100644 --- a/include/uapi/linux/psample.h +++ b/include/uapi/linux/psample.h @@ -3,7 +3,6 @@ #define __UAPI_PSAMPLE_H enum { - /* sampled packet metadata */ PSAMPLE_ATTR_IIFINDEX, PSAMPLE_ATTR_OIFINDEX, PSAMPLE_ATTR_ORIGSIZE, @@ -11,10 +10,8 @@ enum { PSAMPLE_ATTR_GROUP_SEQ, PSAMPLE_ATTR_SAMPLE_RATE, PSAMPLE_ATTR_DATA, - PSAMPLE_ATTR_TUNNEL, - - /* commands attributes */ PSAMPLE_ATTR_GROUP_REFCOUNT, + PSAMPLE_ATTR_TUNNEL, __PSAMPLE_ATTR_MAX }; -- cgit v1.2.3