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2020-08-20saner calling conventions for csum_and_copy_..._user()Al Viro1-9/+6
All callers of these primitives will * discard anything we might've copied in case of error * ignore the csum value in case of error * always pass 0xffffffff as the initial sum, so the resulting csum value (in case of success, that is) will never be 0. That suggest the following calling conventions: * don't pass err_ptr - just return 0 on error. * don't bother with zeroing destination, etc. in case of error * don't pass the initial sum - just use 0xffffffff. This commit does the minimal conversion in the instances of csum_and_copy_...(); the changes of actual asm code behind them are done later in the series. Note that this asm code is often shared with csum_partial_copy_nocheck(); the difference is that csum_partial_copy_nocheck() passes 0 for initial sum while csum_and_copy_..._user() pass 0xffffffff. Fortunately, we are free to pass 0xffffffff in all cases and subsequent patches will use that freedom without any special comments. A part that could be split off: parisc and uml/i386 claimed to have csum_and_copy_to_user() instances of their own, but those were identical to the generic one, so we simply drop them. Not sure if it's worth a separate commit... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20csum_partial_copy_nocheck(): drop the last argumentAl Viro1-2/+2
It's always 0. Note that we theoretically could use ~0U as well - result will be the same modulo 0xffff, _if_ the damn thing did the right thing for any value of initial sum; later we'll make use of that when convenient. However, unlike csum_and_copy_..._user(), there are instances that did not work for arbitrary initial sums; c6x is one such. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20unify generic instances of csum_partial_copy_nocheck()Al Viro1-0/+9
quite a few architectures have the same csum_partial_copy_nocheck() - simply memcpy() the data and then return the csum of the copy. hexagon, parisc, ia64, s390, um: explicitly spelled out that way. arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32, nios2, openrisc, riscv, unicore32: end up picking the same thing spelled out in lib/checksum.h (with varying amounts of perversions along the way). everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc, sh, sparc, x86, xtensa) have non-generic variants. For all except c6x the declaration is in their asm/checksum.h. c6x uses the wrapper from asm-generic/checksum.h that would normally lead to the lib/checksum.h instance, but in case of c6x we end up using an asm function from arch/c6x instead. Screw that mess - have architectures with private instances define _HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY *not* defined. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-29default csum_and_copy_to_user(): don't bother with access_ok()Al Viro1-4/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-29take the dummy csum_and_copy_from_user() into net/checksum.hAl Viro1-6/+2
now that can be done conveniently - all non-trivial cases have _HAVE_ARCH_COPY_AND_CSUM_FROM_USER defined, so the fallback in net/checksum.h is used only for dummy (copy_from_user, then csum_partial) implementation. Allowing us to get rid of all dummy instances, both of csum_and_copy_from_user() and csum_partial_copy_from_user(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-03Remove 'type' argument from access_ok() functionLinus Torvalds1-2/+2
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-20csum: eliminate sparse warning in remcsum_unadjust()Lance Richardson1-1/+1
Cast second parameter of csum_sub() from __sum16 to __wsum. Signed-off-by: Lance Richardson <lrichard@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds1-1/+1
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-13csum: Update csum_block_add to use rotate instead of byteswapAlexander Duyck1-6/+6
The code for csum_block_add was doing a funky byteswap to swap the even and odd bytes of the checksum if the offset was odd. Instead of doing this we can save ourselves some trouble and just shift by 8 as this should have the same effect in terms of the final checksum value and only requires one instruction. In addition we can update csum_block_sub to just use csum_block_add with a inverse value for csum2. This way we follow the same code path as csum_block_add without having to duplicate it. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08bpf: allow bpf_csum_diff to feed bpf_l3_csum_replace as wellDaniel Borkmann1-0/+5
Commit 7d672345ed29 ("bpf: add generic bpf_csum_diff helper") added a generic checksum diff helper that can feed bpf_l4_csum_replace() with a target __wsum diff that is to be applied to the L4 checksum. This facility is very flexible, can be cascaded, allows for adding, removing, or diffing data, or for calculating the pseudo header checksum from scratch, but it can also be reused for working with the IPv4 header checksum. Thus, analogous to bpf_l4_csum_replace(), add a case for header field value of 0 to change the checksum at a given offset through a new helper csum_replace_by_diff(). Also, in addition to that, this provides an easy to use interface for feeding precalculated diffs f.e. coming from a map. It nicely complements bpf_l3_csum_replace() that currently allows only for csum updates of 2 and 4 byte diffs. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-13rco: Clean up casting errorsTom Herbert1-1/+2
Fixe a couple of cast errors found by sparse. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17net: Add inet_proto_csum_replace_by_diff utility functionTom Herbert1-0/+2
This function updates a checksum field value and skb->csum based on a value which is the difference between the old and new checksum. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17net: Change pseudohdr argument of inet_proto_csum_replace* to be a boolTom Herbert1-3/+3
inet_proto_csum_replace4,2,16 take a pseudohdr argument which indicates the checksum field carries a pseudo header. This argument should be a boolean instead of an int. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17net: fix sparse error in csum_replace4()Eric Dumazet1-1/+3
make C=2 CF=-D__CHECK_ENDIAN__ net/ipv4/netfilter/nf_nat_l3proto_ipv4.o CHECK net/ipv4/netfilter/nf_nat_l3proto_ipv4.c include/net/checksum.h:125:64: warning: incorrect type in argument 2 (different base types) include/net/checksum.h:125:64: expected restricted __wsum [usertype] addend include/net/checksum.h:125:64: got restricted __be32 [usertype] from include/net/checksum.h:125:71: warning: incorrect type in argument 2 (different base types) include/net/checksum.h:125:71: expected restricted __wsum [usertype] addend include/net/checksum.h:125:71: got restricted __be32 [usertype] to include/net/checksum.h:125:64: warning: incorrect type in argument 2 (different base types) include/net/checksum.h:125:64: expected restricted __wsum [usertype] addend include/net/checksum.h:125:64: got restricted __be32 [usertype] from include/net/checksum.h:125:71: warning: incorrect type in argument 2 (different base types) include/net/checksum.h:125:71: expected restricted __wsum [usertype] addend include/net/checksum.h:125:71: got restricted __be32 [usertype] to Fixes: 4565af0d406b ("net: optimise csum_replace4()") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-11net: Fix remcsum in GRO path to not change packetTom Herbert1-0/+5
Remote checksum offload processing is currently the same for both the GRO and non-GRO path. When the remote checksum offload option is encountered, the checksum field referred to is modified in the packet. So in the GRO case, the packet is modified in the GRO path and then the operation is skipped when the packet goes through the normal path based on skb->remcsum_offload. There is a problem in that the packet may be modified in the GRO path, but then forwarded off host still containing the remote checksum option. A remote host will again perform RCO but now the checksum verification will fail since GRO RCO already modified the checksum. To fix this, we ensure that GRO restores a packet to it's original state before returning. In this model, when GRO processes a remote checksum option it still changes the checksum per the algorithm but on return from lower layer processing the checksum is restored to its original value. In this patch we add define gro_remcsum structure which is passed to skb_gro_remcsum_process to save offset and delta for the checksum being changed. After lower layer processing, skb_gro_remcsum_cleanup is called to restore the checksum before returning from GRO. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-26net: Add remcsum_adjust as common function for remote checksum offloadTom Herbert1-0/+16
This function does the work to update a checksum field as part of remote checksum offload. remcsum_adjust does the following: 1) Subtract out the calculated checksum from the beginning of the packet (ptr arg) to the start offset. 2) Adjust the checksum field indicated by offset based on the modified checksum value from above step. 3) Return the difference in the old checksum field value and the new one. The caller will use this to update skb->csum and NAPI csum. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-26net: optimise csum_replace4()LEROY Christophe1-3/+1
csum_partial() is a generic function which is not optimised for small fixed length calculations, and its use requires to store "from" and "to" values in memory while we already have them available in registers. This also has impact, especially on RISC processors. In the same spirit as the change done by Eric Dumazet on csum_replace2(), this patch rewrites inet_proto_csum_replace4() taking into account RFC1624. I spotted during a NATted tcp transfert that csum_partial() is one of top 5 consuming functions (around 8%), and the second user of csum_partial() is inet_proto_csum_replace4(). I have proposed the same modification to inet_proto_csum_replace4() in another patch. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-05net: Allow csum_add to be provided in archTom Herbert1-0/+2
csum_add is really nothing more then add-with-carry which can be implemented efficiently in some architectures. Allow architecture to define this protected by HAVE_ARCH_CSUM_ADD. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-24net: optimize csum_replace2()Eric Dumazet1-2/+21
When changing one 16bit value by another in IP header, we can adjust the IP checksum by doing a simple operation described in RFC 1624, as reminded by David. csum_partial() is a complex function on x86_64, not really suited for small number of checksummed bytes. I spotted csum_partial() being in the top 20 most consuming functions (more than 1 %) in a GRO workload, which was rather unexpected. The caller was inet_gro_complete() doing a csum_replace2() when building the new IP header for the GRO packet. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-04net: checksum: fix warning in skb_checksumDaniel Borkmann1-0/+5
This patch fixes a build warning in skb_checksum() by wrapping the csum_partial() usage in skb_checksum(). The problem is that on a few architectures, csum_partial is used with prefix asmlinkage whereas on most architectures it's not. So fix this up generically as we did with csum_block_add_ext() to match the signature. Introduced by 2817a336d4d ("net: skb_checksum: allow custom update/combine for walking skb"). Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-03net: skb_checksum: allow custom update/combine for walking skbDaniel Borkmann1-0/+6
Currently, skb_checksum walks over 1) linearized, 2) frags[], and 3) frag_list data and calculats the one's complement, a 32 bit result suitable for feeding into itself or csum_tcpudp_magic(), but unsuitable for SCTP as we're calculating CRC32c there. Hence, in order to not re-implement the very same function in SCTP (and maybe other protocols) over and over again, use an update() + combine() callback internally to allow for walking over the skb with different algorithms. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-31checksum: Remove extern from function prototypesJoe Perches1-5/+5
There are a mix of function prototypes with and without extern in the kernel sources. Standardize on not using extern for function prototypes. Function prototypes don't need to be written with extern. extern is assumed by the compiler. Its use is as unnecessary as using auto to declare automatic/local variables in a block. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-30net: core: add function for incremental IPv6 pseudo header checksum updatesPatrick McHardy1-0/+3
Add inet_proto_csum_replace16 for incrementally updating IPv6 pseudo header checksums for IPv6 NAT. Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: David S. Miller <davem@davemloft.net>
2008-11-19include/net net/ - csum_partial - remove unnecessary castsJoe Perches1-1/+1
The first argument to csum_partial is const void * casts to char/u8 * are not necessary Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28[NET]: Move netfilter checksum helpers to net/core/utils.cPatrick McHardy1-0/+25
This allows to get rid of the CONFIG_NETFILTER dependency of NET_ACT_NAT. This patch redefines the old names to keep the noise low, the next patch converts all users. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET]: Make mangling a checksum (0 -> 0xffff on the wire) explicit.Al Viro1-0/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET]: Generic checksum annotations and cleanups.Al Viro1-17/+25
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+87
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!