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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
// SPDX-License-Identifier: GPL-2.0
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* The IP forwarding functionality.
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
*
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* Authors: see ip.c
*
* Fixes:
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
* Many : Split from ip.c , see ip_input.c for
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* history.
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
* Dave Gregorich : NULL ip_rt_put fix for multicast
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* routing.
* Jos Vos : Add call_out_firewall before sending,
* use output device for accounting.
* Jos Vos : Call forward firewall after routing
* (always use output device).
* Mike McLagan : Routing by source
*/
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/icmp.h>
#include <linux/netdevice.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
#include <net/sock.h>
#include <net/ip.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/icmp.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/netfilter_ipv4.h>
#include <net/checksum.h>
#include <linux/route.h>
#include <net/route.h>
#include <net/xfrm.h>
net: ip, ipv6: handle gso skbs in forwarding path Marcelo Ricardo Leitner reported problems when the forwarding link path has a lower mtu than the incoming one if the inbound interface supports GRO. Given: Host <mtu1500> R1 <mtu1200> R2 Host sends tcp stream which is routed via R1 and R2. R1 performs GRO. In this case, the kernel will fail to send ICMP fragmentation needed messages (or pkt too big for ipv6), as GSO packets currently bypass dstmtu checks in forward path. Instead, Linux tries to send out packets exceeding the mtu. When locking route MTU on Host (i.e., no ipv4 DF bit set), R1 does not fragment the packets when forwarding, and again tries to send out packets exceeding R1-R2 link mtu. This alters the forwarding dstmtu checks to take the individual gso segment lengths into account. For ipv6, we send out pkt too big error for gso if the individual segments are too big. For ipv4, we either send icmp fragmentation needed, or, if the DF bit is not set, perform software segmentation and let the output path create fragments when the packet is leaving the machine. It is not 100% correct as the error message will contain the headers of the GRO skb instead of the original/segmented one, but it seems to work fine in my (limited) tests. Eric Dumazet suggested to simply shrink mss via ->gso_size to avoid sofware segmentation. However it turns out that skb_segment() assumes skb nr_frags is related to mss size so we would BUG there. I don't want to mess with it considering Herbert and Eric disagree on what the correct behavior should be. Hannes Frederic Sowa notes that when we would shrink gso_size skb_segment would then also need to deal with the case where SKB_MAX_FRAGS would be exceeded. This uses sofware segmentation in the forward path when we hit ipv4 non-DF packets and the outgoing link mtu is too small. Its not perfect, but given the lack of bug reports wrt. GRO fwd being broken this is a rare case anyway. Also its not like this could not be improved later once the dust settles. Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Reported-by: Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-14 06:09:12 +08:00
static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
{
net: ipv4: ip_forward: fix inverted local_df test local_df means 'ignore DF bit if set', so if its set we're allowed to perform ip fragmentation. This wasn't noticed earlier because the output path also drops such skbs (and emits needed icmp error) and because netfilter ip defrag did not set local_df until couple of days ago. Only difference is that DF-packets-larger-than MTU now discarded earlier (f.e. we avoid pointless netfilter postrouting trip). While at it, drop the repeated test ip_exceeds_mtu, checking it once is enough... Fixes: fe6cc55f3a9 ("net: ip, ipv6: handle gso skbs in forwarding path") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-05 05:24:31 +08:00
if (skb->len <= mtu)
net: ip, ipv6: handle gso skbs in forwarding path Marcelo Ricardo Leitner reported problems when the forwarding link path has a lower mtu than the incoming one if the inbound interface supports GRO. Given: Host <mtu1500> R1 <mtu1200> R2 Host sends tcp stream which is routed via R1 and R2. R1 performs GRO. In this case, the kernel will fail to send ICMP fragmentation needed messages (or pkt too big for ipv6), as GSO packets currently bypass dstmtu checks in forward path. Instead, Linux tries to send out packets exceeding the mtu. When locking route MTU on Host (i.e., no ipv4 DF bit set), R1 does not fragment the packets when forwarding, and again tries to send out packets exceeding R1-R2 link mtu. This alters the forwarding dstmtu checks to take the individual gso segment lengths into account. For ipv6, we send out pkt too big error for gso if the individual segments are too big. For ipv4, we either send icmp fragmentation needed, or, if the DF bit is not set, perform software segmentation and let the output path create fragments when the packet is leaving the machine. It is not 100% correct as the error message will contain the headers of the GRO skb instead of the original/segmented one, but it seems to work fine in my (limited) tests. Eric Dumazet suggested to simply shrink mss via ->gso_size to avoid sofware segmentation. However it turns out that skb_segment() assumes skb nr_frags is related to mss size so we would BUG there. I don't want to mess with it considering Herbert and Eric disagree on what the correct behavior should be. Hannes Frederic Sowa notes that when we would shrink gso_size skb_segment would then also need to deal with the case where SKB_MAX_FRAGS would be exceeded. This uses sofware segmentation in the forward path when we hit ipv4 non-DF packets and the outgoing link mtu is too small. Its not perfect, but given the lack of bug reports wrt. GRO fwd being broken this is a rare case anyway. Also its not like this could not be improved later once the dust settles. Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Reported-by: Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-14 06:09:12 +08:00
return false;
ip: reject too-big defragmented DF-skb when forwarding Send icmp pmtu error if we find that the largest fragment of df-skb exceeded the output path mtu. The ip output path will still catch this later on but we can avoid the forward/postrouting hook traversal by rejecting right away. This is what ipv6 already does. Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 06:06:40 +08:00
if (unlikely((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0))
return false;
/* original fragment exceeds mtu and DF is set */
if (unlikely(IPCB(skb)->frag_max_size > mtu))
return true;
if (skb->ignore_df)
return false;
net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len If you take a GSO skb, and split it into packets, will the network length (L3 headers + L4 headers + payload) of those packets be small enough to fit within a given MTU? skb_gso_validate_mtu gives you the answer to that question. However, we recently added to add a way to validate the MAC length of a split GSO skb (L2+L3+L4+payload), and the names get confusing, so rename skb_gso_validate_mtu to skb_gso_validate_network_len Signed-off-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-01 14:13:37 +08:00
if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
net: ip, ipv6: handle gso skbs in forwarding path Marcelo Ricardo Leitner reported problems when the forwarding link path has a lower mtu than the incoming one if the inbound interface supports GRO. Given: Host <mtu1500> R1 <mtu1200> R2 Host sends tcp stream which is routed via R1 and R2. R1 performs GRO. In this case, the kernel will fail to send ICMP fragmentation needed messages (or pkt too big for ipv6), as GSO packets currently bypass dstmtu checks in forward path. Instead, Linux tries to send out packets exceeding the mtu. When locking route MTU on Host (i.e., no ipv4 DF bit set), R1 does not fragment the packets when forwarding, and again tries to send out packets exceeding R1-R2 link mtu. This alters the forwarding dstmtu checks to take the individual gso segment lengths into account. For ipv6, we send out pkt too big error for gso if the individual segments are too big. For ipv4, we either send icmp fragmentation needed, or, if the DF bit is not set, perform software segmentation and let the output path create fragments when the packet is leaving the machine. It is not 100% correct as the error message will contain the headers of the GRO skb instead of the original/segmented one, but it seems to work fine in my (limited) tests. Eric Dumazet suggested to simply shrink mss via ->gso_size to avoid sofware segmentation. However it turns out that skb_segment() assumes skb nr_frags is related to mss size so we would BUG there. I don't want to mess with it considering Herbert and Eric disagree on what the correct behavior should be. Hannes Frederic Sowa notes that when we would shrink gso_size skb_segment would then also need to deal with the case where SKB_MAX_FRAGS would be exceeded. This uses sofware segmentation in the forward path when we hit ipv4 non-DF packets and the outgoing link mtu is too small. Its not perfect, but given the lack of bug reports wrt. GRO fwd being broken this is a rare case anyway. Also its not like this could not be improved later once the dust settles. Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Reported-by: Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-14 06:09:12 +08:00
return false;
return true;
}
netfilter: Pass net into okfn This is immediately motivated by the bridge code that chains functions that call into netfilter. Without passing net into the okfns the bridge code would need to guess about the best expression for the network namespace to process packets in. As net is frequently one of the first things computed in continuation functions after netfilter has done it's job passing in the desired network namespace is in many cases a code simplification. To support this change the function dst_output_okfn is introduced to simplify passing dst_output as an okfn. For the moment dst_output_okfn just silently drops the struct net. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-16 09:04:18 +08:00
static int ip_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
{
ipv4: fix checkpatch errors Fix checkpatch errors of the following type: * ERROR: "foo * bar" should be "foo *bar" * ERROR: "(foo*)" should be "(foo *)" Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 09:34:41 +08:00
struct ip_options *opt = &(IPCB(skb)->opt);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
net: Do not route unicast IP packets twice Packets marked with 'offload_l3_fwd_mark' were already forwarded by a capable device and should not be forwarded again by the kernel. Therefore, have the kernel consume them. The check is performed in ip{,6}_forward_finish() in order to allow the kernel to process such packets in ip{,6}_forward() and generate required exceptions. For example, ICMP redirects. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-04 16:15:11 +08:00
#ifdef CONFIG_NET_SWITCHDEV
if (skb->offload_l3_fwd_mark) {
consume_skb(skb);
return 0;
}
#endif
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
if (unlikely(opt->optlen))
ip_forward_options(skb);
net: Add skb_clear_tstamp() to keep the mono delivery_time Right now, skb->tstamp is reset to 0 whenever the skb is forwarded. If skb->tstamp has the mono delivery_time, clearing it can hurt the performance when it finally transmits out to fq@phy-dev. The earlier patch added a skb->mono_delivery_time bit to flag the skb->tstamp carrying the mono delivery_time. This patch adds skb_clear_tstamp() helper which keeps the mono delivery_time and clears everything else. The delivery_time clearing will be postponed until the stack knows the skb will be delivered locally. It will be done in a latter patch. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-03 03:55:31 +08:00
skb_clear_tstamp(skb);
net: Pass net into dst_output and remove dst_output_okfn Replace dst_output_okfn with dst_output Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 05:48:35 +08:00
return dst_output(net, sk, skb);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
}
int ip_forward(struct sk_buff *skb)
{
ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing While forwarding we should not use the protocol path mtu to calculate the mtu for a forwarded packet but instead use the interface mtu. We mark forwarded skbs in ip_forward with IPSKB_FORWARDED, which was introduced for multicast forwarding. But as it does not conflict with our usage in unicast code path it is perfect for reuse. I moved the functions ip_sk_accept_pmtu, ip_sk_use_pmtu and ip_skb_dst_mtu along with the new ip_dst_mtu_maybe_forward to net/ip.h to fix circular dependencies because of IPSKB_FORWARDED. Because someone might have written a software which does probe destinations manually and expects the kernel to honour those path mtus I introduced a new per-namespace "ip_forward_use_pmtu" knob so someone can disable this new behaviour. We also still use mtus which are locked on a route for forwarding. The reason for this change is, that path mtus information can be injected into the kernel via e.g. icmp_err protocol handler without verification of local sockets. As such, this could cause the IPv4 forwarding path to wrongfully emit fragmentation needed notifications or start to fragment packets along a path. Tunnel and ipsec output paths clear IPCB again, thus IPSKB_FORWARDED won't be set and further fragmentation logic will use the path mtu to determine the fragmentation size. They also recheck packet size with help of path mtu discovery and report appropriate errors. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: John Heffner <johnwheffner@gmail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-09 17:01:15 +08:00
u32 mtu;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
struct iphdr *iph; /* Our header */
struct rtable *rt; /* Route we use */
ipv4: fix checkpatch errors Fix checkpatch errors of the following type: * ERROR: "foo * bar" should be "foo *bar" * ERROR: "(foo*)" should be "(foo *)" Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-15 09:34:41 +08:00
struct ip_options *opt = &(IPCB(skb)->opt);
ipv4: Compute net once in ip_forward Compute struct net from the input device in ip_forward before it is used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-16 09:03:54 +08:00
struct net *net;
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
SKB_DR(reason);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
ipv4: ip_forward: perform skb->pkt_type check at the beginning Packets which have L2 address different from ours should be already filtered before entering into ip_forward(). Perform that check at the beginning to avoid processing such packets. Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 12:58:56 +08:00
/* that should never happen */
if (skb->pkt_type != PACKET_HOST)
goto drop;
ip_forward: Drop frames with attached skb->sk Initial discussion was: [FYI] xfrm: Don't lookup sk_policy for timewait sockets Forwarded frames should not have a socket attached. Especially tw sockets will lead to panics later-on in the stack. This was observed with TPROXY assigning a tw socket and broken policy routing (misconfigured). As a result frame enters forwarding path instead of input. We cannot solve this in TPROXY as it cannot know that policy routing is broken. v2: Remove useless comment Signed-off-by: Sebastian Poehn <sebastian.poehn@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-20 15:19:20 +08:00
if (unlikely(skb->sk))
goto drop;
net: Discard and warn about LRO'd skbs received for forwarding Add skb_warn_if_lro() to test whether an skb was received with LRO and warn if so. Change br_forward(), ip_forward() and ip6_forward() to call it) and discard the skb if it returns true. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-20 07:22:28 +08:00
if (skb_warn_if_lro(skb))
goto drop;
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
if (!xfrm4_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
SKB_DR_SET(reason, XFRM_POLICY);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
goto drop;
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
}
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
if (IPCB(skb)->opt.router_alert && ip_call_ra_chain(skb))
return NET_RX_SUCCESS;
[NET]: Allow forwarding of ip_summed except CHECKSUM_COMPLETE Right now Xen has a horrible hack that lets it forward packets with partial checksums. One of the reasons that CHECKSUM_PARTIAL and CHECKSUM_COMPLETE were added is so that we can get rid of this hack (where it creates two extra bits in the skbuff to essentially mirror ip_summed without being destroyed by the forwarding code). I had forgotten that I've already gone through all the deivce drivers last time around to make sure that they're looking at ip_summed == CHECKSUM_PARTIAL rather than ip_summed != 0 on transmit. In any case, I've now done that again so it should definitely be safe. Unfortunately nobody has yet added any code to update CHECKSUM_COMPLETE values on forward so we I'm setting that to CHECKSUM_NONE. This should be safe to remove for bridging but I'd like to check that code path first. So here is the patch that lets us get rid of the hack by preserving ip_summed (mostly) on forwarded packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-27 14:22:20 +08:00
skb_forward_csum(skb);
ipv4: Compute net once in ip_forward Compute struct net from the input device in ip_forward before it is used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-16 09:03:54 +08:00
net = dev_net(skb->dev);
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/*
* According to the RFC, we must first decrease the TTL field. If
* that reaches zero, we must reply an ICMP control message telling
* that the packet's lifetime expired.
*/
[SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-21 13:47:35 +08:00
if (ip_hdr(skb)->ttl <= 1)
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
goto too_many_hops;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
if (!xfrm4_route_forward(skb)) {
SKB_DR_SET(reason, XFRM_POLICY);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
goto drop;
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
}
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
net: skb->rtable accessor Define skb_rtable(const struct sk_buff *skb) accessor to get rtable from skb Delete skb->rtable field Setting rtable is not allowed, just set dst instead as rtable is an alias. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-02 13:14:27 +08:00
rt = skb_rtable(skb);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
ipv4: Revert removal of rt_uses_gateway Julian noted that rt_uses_gateway has a more subtle use than 'is gateway set': https://lore.kernel.org/netdev/alpine.LFD.2.21.1909151104060.2546@ja.home.ssi.bg/ Revert that part of the commit referenced in the Fixes tag. Currently, there are no u8 holes in 'struct rtable'. There is a 4-byte hole in the second cacheline which contains the gateway declaration. So move rt_gw_family down to the gateway declarations since they are always used together, and then re-use that u8 for rt_uses_gateway. End result is that rtable size is unchanged. Fixes: 1550c171935d ("ipv4: Prepare rtable for IPv6 gateway") Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-09-18 01:39:49 +08:00
if (opt->is_strictroute && rt->rt_uses_gateway)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
goto sr_failed;
net: fix IPSTATS_MIB_OUTFORWDATAGRAMS increment after fragment check Reproduce environment: network with 3 VM linuxs is connected as below: VM1<---->VM2(latest kernel 6.5.0-rc7)<---->VM3 VM1: eth0 ip: 192.168.122.207 MTU 1800 VM2: eth0 ip: 192.168.122.208, eth1 ip: 192.168.123.224 MTU 1500 VM3: eth0 ip: 192.168.123.240 MTU 1800 Reproduce: VM1 send 1600 bytes UDP data to VM3 using tools scapy with flags='DF'. scapy command: send(IP(dst="192.168.123.240",flags='DF')/UDP()/str('0'*1600),count=1, inter=1.000000) Result: Before IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss Ip: 1 64 6 0 2 2 0 0 2 4 0 0 0 0 0 0 0 0 0 ...... root@qemux86-64:~# ---------------------------------------------------------------------- After IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss Ip: 1 64 7 0 2 2 0 0 2 5 0 0 0 0 0 0 0 1 0 ...... root@qemux86-64:~# ---------------------------------------------------------------------- ForwDatagrams is always keeping 2 without increment. Issue description and patch: ip_exceeds_mtu() in ip_forward() drops this IP datagram because skb len (1600 sending by scapy) is over MTU(1500 in VM2) if "DF" is set. According to RFC 4293 "3.2.3. IP Statistics Tables", +-------+------>------+----->-----+----->-----+ | InForwDatagrams (6) | OutForwDatagrams (6) | | V +->-+ OutFragReqds | InNoRoutes | | (packets) / (local packet (3) | | | IF is that of the address | +--> OutFragFails | and may not be the receiving IF) | | (packets) the IPSTATS_MIB_OUTFORWDATAGRAMS should be counted before fragment check. The existing implementation, instead, would incease the counter after fragment check: ip_exceeds_mtu() in ipv4 and ip6_pkt_too_big() in ipv6. So do patch to move IPSTATS_MIB_OUTFORWDATAGRAMS counter to ip_forward() for ipv4 and ip6_forward() for ipv6. Test result with patch: Before IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss Ip: 1 64 6 0 2 2 0 0 2 4 0 0 0 0 0 0 0 0 0 ...... root@qemux86-64:~# ---------------------------------------------------------------------- After IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqdss Ip: 1 64 7 0 2 3 0 0 2 5 0 0 0 0 0 0 0 1 0 ...... root@qemux86-64:~# ---------------------------------------------------------------------- ForwDatagrams is updated from 2 to 3. Reviewed-by: Filip Pudak <filip.pudak@windriver.com> Signed-off-by: Heng Guo <heng.guo@windriver.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20231011015137.27262-1-heng.guo@windriver.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-11 09:51:37 +08:00
__IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
ipv4: allow local fragmentation in ip_finish_output_gso() Some configurations (e.g. geneve interface with default MTU of 1500 over an ethernet interface with 1500 MTU) result in the transmission of packets that exceed the configured MTU. While this should be considered to be a "bad" configuration, it is still allowed and should not result in the sending of packets that exceed the configured MTU. Fix by dropping the assumption in ip_finish_output_gso() that locally originated gso packets will never need fragmentation. Basic testing using iperf (observing CPU usage and bandwidth) have shown no measurable performance impact for traffic not requiring fragmentation. Fixes: c7ba65d7b649 ("net: ip: push gso skb forwarding handling down the stack") Reported-by: Jan Tluka <jtluka@redhat.com> Signed-off-by: Lance Richardson <lrichard@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-03 04:36:17 +08:00
IPCB(skb)->flags |= IPSKB_FORWARDED;
ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing While forwarding we should not use the protocol path mtu to calculate the mtu for a forwarded packet but instead use the interface mtu. We mark forwarded skbs in ip_forward with IPSKB_FORWARDED, which was introduced for multicast forwarding. But as it does not conflict with our usage in unicast code path it is perfect for reuse. I moved the functions ip_sk_accept_pmtu, ip_sk_use_pmtu and ip_skb_dst_mtu along with the new ip_dst_mtu_maybe_forward to net/ip.h to fix circular dependencies because of IPSKB_FORWARDED. Because someone might have written a software which does probe destinations manually and expects the kernel to honour those path mtus I introduced a new per-namespace "ip_forward_use_pmtu" knob so someone can disable this new behaviour. We also still use mtus which are locked on a route for forwarding. The reason for this change is, that path mtus information can be injected into the kernel via e.g. icmp_err protocol handler without verification of local sockets. As such, this could cause the IPv4 forwarding path to wrongfully emit fragmentation needed notifications or start to fragment packets along a path. Tunnel and ipsec output paths clear IPCB again, thus IPSKB_FORWARDED won't be set and further fragmentation logic will use the path mtu to determine the fragmentation size. They also recheck packet size with help of path mtu discovery and report appropriate errors. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: John Heffner <johnwheffner@gmail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-09 17:01:15 +08:00
mtu = ip_dst_mtu_maybe_forward(&rt->dst, true);
ip: reject too-big defragmented DF-skb when forwarding Send icmp pmtu error if we find that the largest fragment of df-skb exceeded the output path mtu. The ip output path will still catch this later on but we can avoid the forward/postrouting hook traversal by rejecting right away. This is what ipv6 already does. Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 06:06:40 +08:00
if (ip_exceeds_mtu(skb, mtu)) {
ipv4: Compute net once in ip_forward Compute struct net from the input device in ip_forward before it is used. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-16 09:03:54 +08:00
IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
[NET] Move DF check to ip_forward Do fragmentation check in ip_forward, similar to ipv6 forwarding. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-26 14:32:29 +08:00
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing While forwarding we should not use the protocol path mtu to calculate the mtu for a forwarded packet but instead use the interface mtu. We mark forwarded skbs in ip_forward with IPSKB_FORWARDED, which was introduced for multicast forwarding. But as it does not conflict with our usage in unicast code path it is perfect for reuse. I moved the functions ip_sk_accept_pmtu, ip_sk_use_pmtu and ip_skb_dst_mtu along with the new ip_dst_mtu_maybe_forward to net/ip.h to fix circular dependencies because of IPSKB_FORWARDED. Because someone might have written a software which does probe destinations manually and expects the kernel to honour those path mtus I introduced a new per-namespace "ip_forward_use_pmtu" knob so someone can disable this new behaviour. We also still use mtus which are locked on a route for forwarding. The reason for this change is, that path mtus information can be injected into the kernel via e.g. icmp_err protocol handler without verification of local sockets. As such, this could cause the IPv4 forwarding path to wrongfully emit fragmentation needed notifications or start to fragment packets along a path. Tunnel and ipsec output paths clear IPCB again, thus IPSKB_FORWARDED won't be set and further fragmentation logic will use the path mtu to determine the fragmentation size. They also recheck packet size with help of path mtu discovery and report appropriate errors. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: John Heffner <johnwheffner@gmail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-09 17:01:15 +08:00
htonl(mtu));
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
SKB_DR_SET(reason, PKT_TOO_BIG);
[NET] Move DF check to ip_forward Do fragmentation check in ip_forward, similar to ipv6 forwarding. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-26 14:32:29 +08:00
goto drop;
}
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/* We are about to mangle packet. Copy it! */
net-next: remove useless union keyword remove useless union keyword in rtable, rt6_info and dn_route. Since there is only one member in a union, the union keyword isn't useful. Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-11 14:31:35 +08:00
if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+rt->dst.header_len))
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
goto drop;
[SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-21 13:47:35 +08:00
iph = ip_hdr(skb);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
/* Decrease ttl after skb cow done */
ip_decrease_ttl(iph);
/*
* We now generate an ICMP HOST REDIRECT giving the route
* we calculated.
*/
ipv4: try to cache dst_entries which would cause a redirect Not caching dst_entries which cause redirects could be exploited by hosts on the same subnet, causing a severe DoS attack. This effect aggravated since commit f88649721268999 ("ipv4: fix dst race in sk_dst_get()"). Lookups causing redirects will be allocated with DST_NOCACHE set which will force dst_release to free them via RCU. Unfortunately waiting for RCU grace period just takes too long, we can end up with >1M dst_entries waiting to be released and the system will run OOM. rcuos threads cannot catch up under high softirq load. Attaching the flag to emit a redirect later on to the specific skb allows us to cache those dst_entries thus reducing the pressure on allocation and deallocation. This issue was discovered by Marcelo Leitner. Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: Marcelo Leitner <mleitner@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-23 19:01:26 +08:00
if (IPCB(skb)->flags & IPSKB_DOREDIRECT && !opt->srr &&
!skb_sec_path(skb))
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
ip_rt_send_redirect(skb);
ip: Fix data-races around sysctl_ip_fwd_update_priority. While reading sysctl_ip_fwd_update_priority, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 432e05d32892 ("net: ipv4: Control SKB reprioritization after forwarding") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-14 04:51:54 +08:00
if (READ_ONCE(net->ipv4.sysctl_ip_fwd_update_priority))
net: ipv4: Control SKB reprioritization after forwarding After IPv4 packets are forwarded, the priority of the corresponding SKB is updated according to the TOS field of IPv4 header. This overrides any prioritization done earlier by e.g. an skbedit action or ingress-qos-map defined at a vlan device. Such overriding may not always be desirable. Even if the packet ends up being routed, which implies this is an L3 network node, an administrator may wish to preserve whatever prioritization was done earlier on in the pipeline. Therefore introduce a sysctl that controls this behavior. Keep the default value at 1 to maintain backward-compatible behavior. Signed-off-by: Petr Machata <petrm@mellanox.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-01 06:36:03 +08:00
skb->priority = rt_tos2priority(iph->tos);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
netfilter: Pass struct net into the netfilter hooks Pass a network namespace parameter into the netfilter hooks. At the call site of the netfilter hooks the path a packet is taking through the network stack is well known which allows the network namespace to be easily and reliabily. This allows the replacement of magic code like "dev_net(state->in?:state->out)" that appears at the start of most netfilter hooks with "state->net". In almost all cases the network namespace passed in is derived from the first network device passed in, guaranteeing those paths will not see any changes in practice. The exceptions are: xfrm/xfrm_output.c:xfrm_output_resume() xs_net(skb_dst(skb)->xfrm) ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont() ip_vs_conn_net(cp) ipvs/ip_vs_xmit.c:ip_vs_send_or_cont() ip_vs_conn_net(cp) ipv4/raw.c:raw_send_hdrinc() sock_net(sk) ipv6/ip6_output.c:ip6_xmit() sock_net(sk) ipv6/ndisc.c:ndisc_send_skb() dev_net(skb->dev) not dev_net(dst->dev) ipv6/raw.c:raw6_send_hdrinc() sock_net(sk) br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev In all cases these exceptions seem to be a better expression for the network namespace the packet is being processed in then the historic "dev_net(in?in:out)". I am documenting them in case something odd pops up and someone starts trying to track down what happened. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-16 09:04:16 +08:00
return NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
net, NULL, skb, skb->dev, rt->dst.dev,
ip_forward_finish);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
sr_failed:
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
/*
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
* Strict routing permits no gatewaying
*/
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0);
goto drop;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
too_many_hops:
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
/* Tell the sender its packet died... */
net: rename IP_INC_STATS_BH() Rename IP_INC_STATS_BH() to __IP_INC_STATS(), to better express this is used in non preemptible context. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-28 07:44:35 +08:00
__IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS);
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-09 22:24:47 +08:00
icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
SKB_DR_SET(reason, IP_INHDR);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
drop:
net: ip: add skb drop reasons to ip forwarding Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Reviewed-by: Hao Peng <flyingpeng@tencent.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 16:15:55 +08:00
kfree_skb_reason(skb, reason);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
return NET_RX_DROP;
}
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