linux-stable.git/net/tls, branch v6.4.3 Linux kernel stable tree tls: improve lockless access safety of tls_err_abort() 2023-05-26T09:35:58+00:00 Jakub Kicinski kuba@kernel.org 2023-05-25T05:17:41+00:00 8a0d57df8938e9fd2e99d47a85b7f37d86f91097 Most protos' poll() methods insert a memory barrier between writes to sk_err and sk_error_report(). This dates back to commit a4d258036ed9 ("tcp: Fix race in tcp_poll"). I guess we should do the same thing in TLS, tcp_poll() does not hold the socket lock. Fixes: 3c4d7559159b ("tls: kernel TLS support") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Most protos' poll() methods insert a memory barrier between
writes to sk_err and sk_error_report(). This dates back to
commit a4d258036ed9 ("tcp: Fix race in tcp_poll").

I guess we should do the same thing in TLS, tcp_poll() does
not hold the socket lock.

Fixes: 3c4d7559159b ("tls: kernel TLS support")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls: rx: strp: don't use GFP_KERNEL in softirq context 2023-05-19T07:37:37+00:00 Jakub Kicinski kuba@kernel.org 2023-05-17T01:50:42+00:00 74836ec828fe17b63f2006fdbf53311d691396bf When receive buffer is small, or the TCP rx queue looks too complicated to bother using it directly - we allocate a new skb and copy data into it. We already use sk->sk_allocation... but nothing actually sets it to GFP_ATOMIC on the ->sk_data_ready() path. Users of HW offload are far more likely to experience problems due to scheduling while atomic. "Copy mode" is very rarely triggered with SW crypto. Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser") Tested-by: Shai Amiram <samiram@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
When receive buffer is small, or the TCP rx queue looks too
complicated to bother using it directly - we allocate a new
skb and copy data into it.

We already use sk->sk_allocation... but nothing actually
sets it to GFP_ATOMIC on the ->sk_data_ready() path.

Users of HW offload are far more likely to experience problems
due to scheduling while atomic. "Copy mode" is very rarely
triggered with SW crypto.

Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser")
Tested-by: Shai Amiram <samiram@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls: rx: strp: preserve decryption status of skbs when needed 2023-05-19T07:37:37+00:00 Jakub Kicinski kuba@kernel.org 2023-05-17T01:50:41+00:00 eca9bfafee3a0487e59c59201ae14c7594ba940a When receive buffer is small we try to copy out the data from TCP into a skb maintained by TLS to prevent connection from stalling. Unfortunately if a single record is made up of a mix of decrypted and non-decrypted skbs combining them into a single skb leads to loss of decryption status, resulting in decryption errors or data corruption. Similarly when trying to use TCP receive queue directly we need to make sure that all the skbs within the record have the same status. If we don't the mixed status will be detected correctly but we'll CoW the anchor, again collapsing it into a single paged skb without decrypted status preserved. So the "fixup" code will not know which parts of skb to re-encrypt. Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser") Tested-by: Shai Amiram <samiram@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
When receive buffer is small we try to copy out the data from
TCP into a skb maintained by TLS to prevent connection from
stalling. Unfortunately if a single record is made up of a mix
of decrypted and non-decrypted skbs combining them into a single
skb leads to loss of decryption status, resulting in decryption
errors or data corruption.

Similarly when trying to use TCP receive queue directly we need
to make sure that all the skbs within the record have the same
status. If we don't the mixed status will be detected correctly
but we'll CoW the anchor, again collapsing it into a single paged
skb without decrypted status preserved. So the "fixup" code will
not know which parts of skb to re-encrypt.

Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser")
Tested-by: Shai Amiram <samiram@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls: rx: strp: factor out copying skb data 2023-05-19T07:37:37+00:00 Jakub Kicinski kuba@kernel.org 2023-05-17T01:50:40+00:00 c1c607b1e5d5477d82ca6a86a05a4f10907b33ee We'll need to copy input skbs individually in the next patch. Factor that code out (without assuming we're copying a full record). Tested-by: Shai Amiram <samiram@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
We'll need to copy input skbs individually in the next patch.
Factor that code out (without assuming we're copying a full record).

Tested-by: Shai Amiram <samiram@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls: rx: strp: fix determining record length in copy mode 2023-05-19T07:37:37+00:00 Jakub Kicinski kuba@kernel.org 2023-05-17T01:50:39+00:00 8b0c0dc9fbbd01e58a573a41c38885f9e4c17696 We call tls_rx_msg_size(skb) before doing skb->len += chunk. So the tls_rx_msg_size() code will see old skb->len, most likely leading to an over-read. Worst case we will over read an entire record, next iteration will try to trim the skb but may end up turning frag len negative or discarding the subsequent record (since we already told TCP we've read it during previous read but now we'll trim it out of the skb). Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser") Tested-by: Shai Amiram <samiram@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
We call tls_rx_msg_size(skb) before doing skb->len += chunk.
So the tls_rx_msg_size() code will see old skb->len, most
likely leading to an over-read.

Worst case we will over read an entire record, next iteration
will try to trim the skb but may end up turning frag len negative
or discarding the subsequent record (since we already told TCP
we've read it during previous read but now we'll trim it out of
the skb).

Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser")
Tested-by: Shai Amiram <samiram@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls: rx: strp: force mixed decrypted records into copy mode 2023-05-19T07:37:37+00:00 Jakub Kicinski kuba@kernel.org 2023-05-17T01:50:38+00:00 14c4be92ebb3e36e392aa9dd8f314038a9f96f3c If a record is partially decrypted we'll have to CoW it, anyway, so go into copy mode and allocate a writable skb right away. This will make subsequent fix simpler because we won't have to teach tls_strp_msg_make_copy() how to copy skbs while preserving decrypt status. Tested-by: Shai Amiram <samiram@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
If a record is partially decrypted we'll have to CoW it, anyway,
so go into copy mode and allocate a writable skb right away.

This will make subsequent fix simpler because we won't have to
teach tls_strp_msg_make_copy() how to copy skbs while preserving
decrypt status.

Tested-by: Shai Amiram <samiram@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls: rx: strp: set the skb->len of detached / CoW'ed skbs 2023-05-19T07:37:37+00:00 Jakub Kicinski kuba@kernel.org 2023-05-17T01:50:37+00:00 210620ae44a83f25220450bbfcc22e6fe986b25f alloc_skb_with_frags() fills in page frag sizes but does not set skb->len and skb->data_len. Set those correctly otherwise device offload will most likely generate an empty skb and hit the BUG() at the end of __skb_nsg(). Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser") Tested-by: Shai Amiram <samiram@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
alloc_skb_with_frags() fills in page frag sizes but does not
set skb->len and skb->data_len. Set those correctly otherwise
device offload will most likely generate an empty skb and
hit the BUG() at the end of __skb_nsg().

Fixes: 84c61fe1a75b ("tls: rx: do not use the standard strparser")
Tested-by: Shai Amiram <samiram@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tls: rx: device: fix checking decryption status 2023-05-19T07:37:37+00:00 Jakub Kicinski kuba@kernel.org 2023-05-17T01:50:36+00:00 b3a03b540e3cf62a255213d084d76d71c02793d5 skb->len covers the entire skb, including the frag_list. In fact we're guaranteed that rxm->full_len <= skb->len, so since the change under Fixes we were not checking decrypt status of any skb but the first. Note that the skb_pagelen() added here may feel a bit costly, but it's removed by subsequent fixes, anyway. Reported-by: Tariq Toukan <tariqt@nvidia.com> Fixes: 86b259f6f888 ("tls: rx: device: bound the frag walk") Tested-by: Shai Amiram <samiram@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
skb->len covers the entire skb, including the frag_list.
In fact we're guaranteed that rxm->full_len <= skb->len,
so since the change under Fixes we were not checking decrypt
status of any skb but the first.

Note that the skb_pagelen() added here may feel a bit costly,
but it's removed by subsequent fixes, anyway.

Reported-by: Tariq Toukan <tariqt@nvidia.com>
Fixes: 86b259f6f888 ("tls: rx: device: bound the frag walk")
Tested-by: Shai Amiram <samiram@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: deal with most data-races in sk_wait_event() 2023-05-10T09:03:32+00:00 Eric Dumazet edumazet@google.com 2023-05-09T18:29:48+00:00 d0ac89f6f9879fae316c155de77b5173b3e2c9c9 __condition is evaluated twice in sk_wait_event() macro. First invocation is lockless, and reads can race with writes, as spotted by syzbot. BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1: tcp_disconnect+0x2cd/0xdb0 inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911 __sys_shutdown_sock net/socket.c:2343 [inline] __sys_shutdown net/socket.c:2355 [inline] __do_sys_shutdown net/socket.c:2363 [inline] __se_sys_shutdown+0xf8/0x140 net/socket.c:2361 __x64_sys_shutdown+0x31/0x40 net/socket.c:2361 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0: sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75 tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484 inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] __sys_sendto+0x246/0x300 net/socket.c:2142 __do_sys_sendto net/socket.c:2154 [inline] __se_sys_sendto net/socket.c:2150 [inline] __x64_sys_sendto+0x78/0x90 net/socket.c:2150 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x00000000 -> 0x00000068 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
__condition is evaluated twice in sk_wait_event() macro.

First invocation is lockless, and reads can race with writes,
as spotted by syzbot.

BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect

write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1:
tcp_disconnect+0x2cd/0xdb0
inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911
__sys_shutdown_sock net/socket.c:2343 [inline]
__sys_shutdown net/socket.c:2355 [inline]
__do_sys_shutdown net/socket.c:2363 [inline]
__se_sys_shutdown+0xf8/0x140 net/socket.c:2361
__x64_sys_shutdown+0x31/0x40 net/socket.c:2361
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0:
sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75
tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484
inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
__sys_sendto+0x246/0x300 net/socket.c:2142
__do_sys_sendto net/socket.c:2154 [inline]
__se_sys_sendto net/socket.c:2150 [inline]
__x64_sys_sendto+0x78/0x90 net/socket.c:2150
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -> 0x00000068

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: tls: fix device-offloaded sendpage straddling records 2023-03-06T21:26:16+00:00 Jakub Kicinski kuba@kernel.org 2023-03-04T19:26:10+00:00 e539a105f947b9db470fec39fe91d85fe737a432 Adrien reports that incorrect data is transmitted when a single page straddles multiple records. We would transmit the same data in all iterations of the loop. Reported-by: Adrien Moulin <amoulin@corp.free.fr> Link: https://lore.kernel.org/all/61481278.42813558.1677845235112.JavaMail.zimbra@corp.free.fr Fixes: c1318b39c7d3 ("tls: Add opt-in zerocopy mode of sendfile()") Tested-by: Adrien Moulin <amoulin@corp.free.fr> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Acked-by: Maxim Mikityanskiy <maxtram95@gmail.com> Link: https://lore.kernel.org/r/20230304192610.3818098-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Adrien reports that incorrect data is transmitted when a single
page straddles multiple records. We would transmit the same
data in all iterations of the loop.

Reported-by: Adrien Moulin <amoulin@corp.free.fr>
Link: https://lore.kernel.org/all/61481278.42813558.1677845235112.JavaMail.zimbra@corp.free.fr
Fixes: c1318b39c7d3 ("tls: Add opt-in zerocopy mode of sendfile()")
Tested-by: Adrien Moulin <amoulin@corp.free.fr>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Acked-by: Maxim Mikityanskiy <maxtram95@gmail.com>
Link: https://lore.kernel.org/r/20230304192610.3818098-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>