linux/include
Chuck Lever 0a8e7b7d08 SUNRPC: Revert 241b1f419f ("SUNRPC: Remove xdr_buf_trim()")
I've noticed that when krb5i or krb5p security is in use,
retransmitted requests are missing the server's duplicate reply
cache. The computed checksum on the retransmitted request does not
match the cached checksum, resulting in the server performing the
retransmitted request again instead of returning the cached reply.

The assumptions made when removing xdr_buf_trim() were not correct.
In the send paths, the upper layer has already set the segment
lengths correctly, and shorting the buffer's content is simply a
matter of reducing buf->len.

xdr_buf_trim() is the right answer in the receive/unwrap path on
both the client and the server. The buffer segment lengths have to
be shortened one-by-one.

On the server side in particular, head.iov_len needs to be updated
correctly to enable nfsd_cache_csum() to work correctly. The simple
buf->len computation doesn't do that, and that results in
checksumming stale data in the buffer.

The problem isn't noticed until there's significant instability of
the RPC transport. At that point, the reliability of retransmit
detection on the server becomes crucial.

Fixes: 241b1f419f ("SUNRPC: Remove xdr_buf_trim()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
History 2020-04-27 10:58:30 -04:00
..
acpi Additional ACPI updates for 5.7-rc1 2020-04-06 10:35:06 -07:00
asm-generic arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h> 2020-04-23 10:50:26 +09:00
clocksource pwm: omap-dmtimer: Drop unused header file 2020-03-30 18:03:06 +02:00
crypto crypto: curve25519 - do not pollute dispatcher based on assembler 2020-04-09 00:01:59 +09:00
drm drm/bridge: analogix_dp: Split bind() into probe() and real bind() 2020-04-09 10:29:35 +02:00
dt-bindings RISC-V Patches for the 5.7 Merge Window, Part 1 2020-04-09 10:51:30 -07:00
keys KEYS: Don't write out to userspace while holding key semaphore 2020-03-29 12:40:41 +01:00
kunit kunit: subtests should be indented 4 spaces according to TAP 2020-03-26 14:08:41 -06:00
kvm KVM: arm64: GICv4.1: Allow SGIs to switch between HW and SW interrupts 2020-03-24 12:15:51 +00:00
linux SUNRPC: Revert 241b1f419f ("SUNRPC: Remove xdr_buf_trim()") 2020-04-27 10:58:30 -04:00
math-emu nds32: Mark expected switch fall-throughs 2019-08-29 11:06:56 -05:00
media media: cec-notifier: make cec_notifier_get_conn() static 2020-03-20 09:02:45 +01:00
misc auxdisplay: charlcd: move charlcd.h to drivers/auxdisplay 2019-08-08 19:59:17 +02:00
net mac80211: populate debugfs only after cfg80211 init 2020-04-24 11:30:13 +02:00
pcmcia It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
ras RAS: Use consistent types for UUIDs 2019-01-25 16:40:40 +01:00
rdma IB/mlx5: Expose UAR object and its alloc/destroy commands 2020-03-27 12:59:04 -03:00
scsi SCSI misc on 20200402 2020-04-02 17:03:53 -07:00
soc ARM: SoC fixes 2020-04-23 09:36:40 -07:00
sound ASoC: Fixes for v5.7 2020-04-21 21:41:36 +02:00
target scsi: target: fix hang when multiple threads try to destroy the same iscsi session 2020-03-26 21:47:47 -04:00
trace block-5.7-2020-04-24 2020-04-24 12:44:19 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-04-24 19:17:30 -07:00
vdso vdso/datapage: Use correct clock mode name in comment 2020-04-20 19:19:52 +02:00
video video: Replace zero-length array with flexible-array member 2020-03-02 16:32:17 +01:00
xen xen: Use evtchn_type_t as a type for event channels 2020-04-07 12:12:54 +02:00