aboutgitcodebugslistschat
Commit message (Collapse)AuthorAgeFilesLines
* selinux: Allow access to user_devpts2024_06_07.8a83b53Derek Schrock2024-06-071-0/+1
| | | | | | | | | | | | | | | | | Allow access to user_devpts. $ pasta --version pasta 0^20240510.g7288448-1.fc40.x86_64 ... $ awk '' < /dev/null $ pasta --version $ While this might be a awk bug it appears pasta should still have access to devpts. Signed-off-by: Derek Schrock <dereks@lifeofadishwasher.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tcp, flow: Fix some error paths which didn't clean up flows properlyDavid Gibson2024-06-071-3/+3
| | | | | | | | | | | | | | | | | | | | Flow table entries need to be fully initialised before returning to the main epoll loop. Commit 0060acd1 ("flow: Clarify and enforce flow state transitions") now enforces that: once a flow is allocated we must either cancel it, or activate it before returning to the main loop, or we will hit an ASSERT(). Some error paths in tcp_conn_from_tap() weren't correctly updated for this requirement - we can exit with a flow entry incompletely initialised. Correct that by cancelling the flows in those situations. I don't have enough information to be certain if this is the cause for podman bug 22925, but it plausibly could be. Fixes: 0060acd11b19 ("flow: Clarify and enforce flow state transitions") Link: https://github.com/containers/podman/issues/22925 Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* util: Use 'long' to represent millisecond durationsDavid Gibson2024-06-072-2/+2
| | | | | | | | | | timespec_diff_ms() returns an int representing a duration in milliseconds. This will overflow in about 25 days when an int is 32 bits. The way we use this function, we're probably not going to get a result that long, but it's not outrageously implausible. Use a long for safety. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* lineread: Use ssize_t for line lengthsDavid Gibson2024-06-073-10/+9
| | | | | | | | | Functions and structures in lineread.c use plain int to record and report the length of lines we receive. This means we truncate the result from read(2) in some circumstances. Use ssize_t to avoid that. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* conf: Safer parsing of MAC addressesDavid Gibson2024-06-071-17/+36
| | | | | | | | | | | | | | | | | In conf() we parse a MAC address in two places, for the --ns-mac-addr and the -M options. As well as duplicating code, the logic for this parsing has several bugs: * The most serious is that if the given string is shorter than a MAC address should be, we'll access past the end of it. * We don't check the endptr supplied by strtol() which means we could ignore certain erroneous contents * We never check the separator characters between each octet * We ignore certain sorts of garbage that follow the MAC address Correct all these bugs in a new parse_mac() helper. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* util: Use unsigned indices for bits in bitmapsDavid Gibson2024-06-072-7/+7
| | | | | | | | | A negative bit index in a bitmap doesn't make sense. Avoid this by construction by using unsigned indices. While we're there adjust bitmap_isset() to return a bool instead of an int. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* clang-tidy: Enable the bugprone-macro-parentheses checkDavid Gibson2024-06-074-26/+25
| | | | | | | | | | | | | | | | We globally disabled this, with a justification lumped together with several checks about braces. They don't really go together, the others are essentially a stylistic choice which doesn't match our style. Omitting brackets on macro parameters can lead to real and hard to track down bugs if an expression is ever passed to the macro instead of a plain identifier. We've only gotten away with the macros which trigger the warning, because of other conventions its been unlikely to invoke them with anything other than a simple identifier. Fix the macros, and enable the warning for the future. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* Remove pointless macro parameters in CALL_PROTO_HANDLERDavid Gibson2024-06-071-3/+3
| | | | | | | | The 'c' parameter is always passed exactly 'c'. The 'now' parameter is always passed exactly 'now'. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* udp: Make rport calculation more localDavid Gibson2024-06-071-2/+1
| | | | | | | | | cppcheck 2.14.1 complains about the rport variable not being in as small as scope as it could be. It's also only used once, so we might as well just open code the calculation for it. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tcp: Make pointer const in tcp_revert_seqDavid Gibson2024-06-071-1/+1
| | | | | | | | | The th pointer could be const, which causes a cppcheck warning on at least some cppcheck versions (e.g. Cppcheck 2.13.0 in Fedora 40). Fixes: e84a01e94c9f ("tcp: move seq_to_tap update to when frame is queued") Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* log: Remove log_to_stdout optionDavid Gibson2024-06-052-6/+3
| | | | | | | | Now that we've simplified how usage() works, nothing ever sets the log_to_stdout flag. Eliminate it. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* conf: Don't print usage via the logging subsystemDavid Gibson2024-06-051-160/+166
| | | | | | | | | | | | | | | | | | | | | | The message from usage() when given invalid options, or the -h / --help option is currently printed by many calls to the info() function, also used for runtime logging of informational messages. That isn't useful: the usage message should always go to the terminal (stdout or stderr), never syslog or a logfile. It should never be filtered by priority. Really the only thing using the common logging functions does is give more opportunities for something to go wrong. Replace all the info() calls with direct fprintf() calls. This does mean manually adding "\n" to each message. A little messy, but worth it for the simplicity in other dimensions. While we're there make much heavier use of single strings containing multiple lines of output text. That reduces the number of fprintf calls, reducing visual clutter and making it easier to see what the output will look like from the source. Link: https://bugs.passt.top/show_bug.cgi?id=90 Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* conf: Remove unhelpful usage() wrapperDavid Gibson2024-06-051-13/+4
| | | | | | | | | usage() does nothing but call print_usage() with EXIT_FAILURE as a parameter. It's no more complex to just give that parameter at the single call site. Eliminate it and rename print_usage() to just usage(). Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tcp: move seq_to_tap update to when frame is queuedJon Maloy2024-06-051-22/+39
| | | | | | | | | | | | | | | | | | | | | | | | commit a469fc393fa1 ("tcp, tap: Don't increase tap-side sequence counter for dropped frames") delayed update of conn->seq_to_tap until the moment the corresponding frame has been successfully pushed out. This has the advantage that we immediately can make a new attempt to transmit a frame after a failed trasnmit, rather than waiting for the peer to later discover a gap and trigger the fast retransmit mechanism to solve the problem. This approach has turned out to cause a problem with spurious sequence number updates during peer-initiated retransmits, and we have realized it may not be the best way to solve the above issue. We now restore the previous method, by updating the said field at the moment a frame is added to the outqueue. To retain the advantage of having a quick re-attempt based on local failure detection, we now scan through the part of the outqueue that had do be dropped, and restore the sequence counter for each affected connection to the most appropriate value. Signed-off-by: Jon Maloy <jmaloy@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* apparmor: Fix comments after PID file and AF_UNIX socket creation refactoring2024_05_23.765eb0bStefano Brivio2024-05-233-7/+13
| | | | | | | | | | | | Now: - we don't open the PID file in main() anymore - PID file and AF_UNIX socket are opened by pidfile_open() and tap_sock_unix_open() - write_pidfile() becomes pidfile_write() Reported-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Acked-by: Richard W.M. Jones <rjones@redhat.com>
* conf, passt.h: Rename pid_file in struct ctx to pidfileStefano Brivio2024-05-232-6/+6
| | | | | | | We have pidfile_fd now, pid_file_fd would be quite ugly. Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
* conf, passt, tap: Open socket and PID files before switching UID/GIDStefano Brivio2024-05-235-11/+28
| | | | | | | | | | | | Otherwise, if the user runs us as root, and gives us paths that are only accessible by root, we'll fail to open them, which might in turn encourage users to change permissions or ownerships: definitely a bad idea in terms of security. Reported-by: Minxi Hou <mhou@redhat.com> Reported-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Acked-by: Richard W.M. Jones <rjones@redhat.com>
* passt, util: Move opening of PID file to its own functionStefano Brivio2024-05-233-9/+25
| | | | | | | We won't call it from main() any longer: move it. Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
* util: Rename write_pidfile() to pidfile_write()Stefano Brivio2024-05-233-5/+5
| | | | | | | | As I'm adding pidfile_open() in the next patch. The function comment didn't match, by the way. Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
* tap: Split tap_sock_unix_init() into opening and listening partsStefano Brivio2024-05-231-12/+27
| | | | | | | | | We'll need to open and bind the socket a while before listening to it, so split that into two different functions. No functional changes intended. Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
* passt, tap: Don't use -1 as uninitialised value for fd_tap_listenStefano Brivio2024-05-232-3/+2
| | | | | | | | | | | | | | This is a remnant from the time we kept access to the original filesystem and we could reinitialise the listening AF_UNIX socket. Since commit 0515adceaa8f ("passt, pasta: Namespace-based sandboxing, defer seccomp policy application"), however, we can't re-bind the listening socket once we're up and running. Drop the -1 initalisation and the corresponding check. Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
* tap: Move all-ones initialisation of mac_guest to tap_sock_init()Stefano Brivio2024-05-231-6/+6
| | | | | | | | | | | | | | | It has nothing to do with tap_sock_unix_init(). It used to be there as that function could be called multiple times per passt instance, but it's not the case anymore. This also takes care of the fact that, with --fd, we wouldn't set the initial MAC address, so we would need to wait for the guest to send us an ARP packet before we could exchange data. Fixes: 6b4e68383c66 ("passt, tap: Add --fd option") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Richard W.M. Jones <rjones@redhat.com>
* conf: Don't lecture user about starting us as rootStefano Brivio2024-05-231-1/+1
| | | | | | | | | | | | | | | libguestfs tools have a good reason to run as root: if the guest image is owned by root, it would be counterproductive to encourage users to invoke them as non-root, as it would require changing permissions or ownership of the image file. And if they run as root, we'll start as root, too. Warn users we'll switch to 'nobody', but don't tell them what to do. Reported-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
* netlink, test: Ignore deprecated addressesDavid Gibson2024-05-226-7/+8
| | | | | | | | | | | | | | When we retrieve or copy host addresses we can include deprecated addresses, which is not what we want. Adjust our logic to exclude them. Similarly our tests can retrieve deprecated addresses, so exclude them there too. I hit this in practice because my router sometimes temporarily advertises an fd00:: prefix before the real delegated IPv6 prefix. The deprecated address can hang around for some time messing up my tests. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tcp: Remove interim 'tapside' field from connectionDavid Gibson2024-05-222-8/+6
| | | | | | | | | | We recently introduced this field to keep track of which side of a TCP flow is the guest/tap facing one. Now that we generically record which pif each side of each flow is connected to, we can easily derive that, and no longer need to keep track of it explicitly. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* flow: Record the pifs for each side of each flowDavid Gibson2024-05-227-16/+109
| | | | | | | | | | | | | | | Currently we have no generic information flows apart from the type and state, everything else is specific to the flow type. Start introducing generic flow information by recording the pifs which the flow connects. To keep track of what information is valid, introduce new flow states: INI for when the initiating side information is complete, and TGT for when both sides information is complete, but we haven't chosen the flow type yet. For now, these states don't do an awful lot, but they'll become more important as we add more generic information. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* flow: Make side 0 always be the initiating sideDavid Gibson2024-05-227-27/+21
| | | | | | | | | | | | | | | | | | | | Each flow in the flow table has two sides, 0 and 1, representing the two interfaces between which passt/pasta will forward data for that flow. Which side is which is currently up to the protocol specific code: TCP uses side 0 for the host/"sock" side and 1 for the guest/"tap" side, except for spliced connections where it uses 0 for the initiating side and 1 for the target side. ICMP also uses 0 for the host/"sock" side and 1 for the guest/"tap" side, but in its case the latter is always also the initiating side. Make this generically consistent by always using side 0 for the initiating side and 1 for the target side. This doesn't simplify a lot for now, and arguably makes TCP slightly more complex, since we add an extra field to the connection structure to record which is the guest facing side. This is an interim change, which we'll be able to remove later. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>q Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* flow: Clarify and enforce flow state transitionsDavid Gibson2024-05-226-69/+183
| | | | | | | | | | | | | | | | | Flows move over several different states in their lifetime. The rules for these are documented in comments, but they're pretty complex and a number of the transitions are implicit, which makes this pretty fragile and error prone. Change the code to explicitly track the states in a field. Make all transitions explicit and logged. To the extent that it's practical in C, enforce what can and can't be done in various states with ASSERT()s. While we're at it, tweak the docs to clarify the restrictions on each state a bit. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* inany: Better helpers for using inany and specific family addrs togetherDavid Gibson2024-05-223-37/+106
| | | | | | | | | This adds some extra inany helpers for comparing an inany address to addresses of a specific family (including special addresses), and building an inany from an IPv4 address (either statically or at runtime). Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* flow: Properly type callbacks to protocol specific handlersDavid Gibson2024-05-226-25/+19
| | | | | | | | | | | | | | | | The flow dispatches deferred and timer handling for flows centrally, but needs to call into protocol specific code for the handling of individual flows. Currently this passes a general union flow *. It makes more sense to pass the specific relevant flow type structure. That brings the check on the flow type adjacent to casting to the union variant which it tags. Arguably, this is a slight abstraction violation since it involves the generic flow code using protocol specific types. It's already calling into protocol specific functions, so I don't think this really makes any difference. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* util, tcp: Add helper to display socket addressesDavid Gibson2024-05-223-14/+79
| | | | | | | | | | | When reporting errors, we sometimes want to show a relevant socket address. Doing so by extracting the various relevant fields can be pretty awkward, so introduce a sockaddr_ntop() helper to make it simpler. For now we just have one user in tcp.c, but I have further upcoming patches which can make use of it. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* apparmor: Fix passt abstractionMaxime Bélair2024-05-221-1/+1
| | | | | | | | | | | | | | | | | | | Commit b686afa2 introduced the invalid apparmor rule `mount options=(rw, runbindable) /,` since runbindable mount rules cannot have a source. Therefore running aa-logprof/aa-genprof will trigger errors (see https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/2065685) $ sudo aa-logprof ERROR: Operation {'runbindable'} cannot have a source. Source = AARE('/') This patch fixes it to the intended behavior. Link: https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/2065685 Fixes: b686afa23e85 ("apparmor: Explicitly pass options we use while remounting root filesystem") Signed-off-by: Maxime Bélair <maxime.belair@canonical.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* apparmor: allow netns paths on /tmpPaul Holzinger2024-05-131-1/+1
| | | | | | | | | | | | | | | For some unknown reason "owner" makes it impossible to open bind mounted netns references as apparmor denies it. In the kernel denied log entry we see ouid=0 but it is not clear why that is as the actual file is owned by the real (rootless) user id. In abstractions/pasta there is already `@{run}/user/@{uid}/**` without owner set for the same reason as this path contains the netns path by default when running under Podman. Fixes: 72884484b00d ("apparmor: allow read access on /tmp for pasta") Signed-off-by: Paul Holzinger <pholzing@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* clang-tidy: Suppress macro to enum conversion warningsDavid Gibson2024-05-131-1/+8
| | | | | | | | | | clang-tidy 18.1.1 in Fedora 40 complains about every #define of an integral value, suggesting it be converted to an enum. Although that's certainly possible, it's of dubious value and results in some awkward arrangements on out codebase. Suppress it globally. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* conf: Fix clang-tidy warning about using an undefined enum valueDavid Gibson2024-05-132-2/+3
| | | | | | | | | | In conf() we temporarily set the forwarding mode variables to 0 - an invalid value, so that we can check later if they've been set by the intervening logic. clang-tidy 18.1.1 in Fedora 40 now complains about this. Satisfy it by giving an name in the enum to the 0 value. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* passt.c: explicitly include libgen.h for basenamelemmi2024-05-131-0/+1
| | | | | | | | fixes implicit declaration warning on musl Signed-off-by: lemmi <lemmi@nerd2nerd.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* netlink: Don't duplicate routes referring to unrelated host interfacesStefano Brivio2024-05-111-6/+33
| | | | | | | | | | | | | | | | | | | | | | | | | We take care of this in nl_addr_dup(): if the interface index associated to an address doesn't match the selected host interface (ifa->ifa_index != ifi_src), we don't copy that address. But for routes, we just unconditionally update the interface index to match the index in the target namespace, even if the source interface didn't match. This might happen in two cases: with a pre-4.20 kernel without support for NETLINK_GET_STRICT_CHK, which won't filter routes based on the interface we pass in the request, as reported by runsisi, and any kernel with support for multipath routes where any of the nexthops refers to an unrelated host interface. In both cases, check the index of the source interface, and avoid copying unrelated routes. Reported-by: runsisi <runsisi@hust.edu.cn> Link: https://bugs.passt.top/show_bug.cgi?id=86 Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Tested-by: runsisi <runsisi@hust.edu.cn> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
* apparmor: allow read access on /tmp for pasta2024_05_10.7288448Paul Holzinger2024-05-101-2/+3
| | | | | | | | | | The podman CI on debian runs tests based on /tmp but pasta is failing there because it is unable to open the netns path as the open for read access is denied. Link: https://github.com/containers/podman/issues/22625 Signed-off-by: Paul Holzinger <pholzing@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tcp_splice: Set OUT_WAIT_ flag whenever pipe isn't emptiedStefano Brivio2024-05-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In tcp_splice_sock_handler(), if we get EAGAIN on the second splice(), from pipe to receiving socket, that doesn't necessarily mean that the pipe is empty: the receiver buffer might be full instead. Hence, we can't use the 'never_read' flag to decide that there's nothing to wait for: even if we didn't read anything from the sending side in a given iteration, we might still have data to send in the pipe. Use read/written counters, instead. This fixes an issue where large bulk transfers would occasionally hang. From a corresponding strace: 0.000061 epoll_wait(4, [{events=EPOLLOUT, data={u32=29442, u64=12884931330}}], 8, 1000) = 1 0.005003 epoll_ctl(4, EPOLL_CTL_MOD, 211, {events=EPOLLIN|EPOLLRDHUP, data={u32=54018, u64=8589988610}}) = 0 0.000089 epoll_ctl(4, EPOLL_CTL_MOD, 115, {events=EPOLLIN|EPOLLRDHUP, data={u32=29442, u64=12884931330}}) = 0 0.000081 splice(211, NULL, 151, NULL, 1048576, SPLICE_F_MOVE|SPLICE_F_NONBLOCK) = -1 EAGAIN (Resource temporarily unavailable) 0.000073 splice(150, NULL, 115, NULL, 1048576, SPLICE_F_MOVE|SPLICE_F_NONBLOCK) = 1048576 0.000087 splice(211, NULL, 151, NULL, 1048576, SPLICE_F_MOVE|SPLICE_F_NONBLOCK) = -1 EAGAIN (Resource temporarily unavailable) 0.000045 splice(150, NULL, 115, NULL, 1048576, SPLICE_F_MOVE|SPLICE_F_NONBLOCK) = 520415 0.000060 splice(211, NULL, 151, NULL, 1048576, SPLICE_F_MOVE|SPLICE_F_NONBLOCK) = -1 EAGAIN (Resource temporarily unavailable) 0.000044 splice(150, NULL, 115, NULL, 1048576, SPLICE_F_MOVE|SPLICE_F_NONBLOCK) = -1 EAGAIN (Resource temporarily unavailable) 0.000044 epoll_wait(4, [], 8, 1000) = 0 we're reading from socket 211 into to the pipe end numbered 151, which connects to pipe end 150, and from there we're writing into socket 115. We initially drop EPOLLOUT from the set of monitored flags for socket 115, because it already signaled it's ready for output. Then we read nothing from socket 211 (the sender had nothing to send), and we keep emptying the pipe into socket 115 (first 1048576 bytes, then 520415 bytes). This call of tcp_splice_sock_handler() ends with EAGAIN on the writing side, and we just exit this function without setting the OUT_WAIT_1 flag (and, in turn, EPOLLOUT for socket 115). However, it turns out, the pipe wasn't actually emptied, and while socket 211 had nothing more to send, we should have waited on socket 115 to be ready for output again. As a further step, we could consider not clearing EPOLLOUT at all, unless the read/written counters match, but I'm first trying to fix this ugly issue with a minimal patch. Link: https://github.com/containers/podman/issues/22575 Link: https://github.com/containers/podman/issues/22593 Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
* udp: Single buffer for IPv4, IPv6 headers and metadataDavid Gibson2024-05-021-77/+55
| | | | | | | | | | | | | | | Currently we have separate arrays for IPv4 and IPv6 which contain the headers for guest-bound packets, and also the originating socket address. We can combine these into a single array of "metadata" structures with space for both pre-cooked IPv4 and IPv6 headers, as well as shared space for the tap specific header and socket address (using sockaddr_inany). Because we're using IOVs to separately address the pieces of each frame, these structures don't need to be packed to keep the headers contiguous so we can more naturally arrange for the alignment we want. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* udp: Use the same buffer for the L2 header for all framesDavid Gibson2024-05-021-21/+15
| | | | | | | | | | Currently each tap-bound frame buffer has room for its own ethernet header. However the ethernet header is always the same for such frames, so now that we're indirectly referencing the ethernet header via iov, we can use a single buffer for all of them. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* udp: Share payload buffers between IPv4 and IPv6David Gibson2024-05-021-59/+67
| | | | | | | | | | | | | | | Currently the IPv4 and IPv6 paths unnecessarily use different buffers for the UDP payload. Now that we're handling the various pieces of the UDP packets with an iov, we can split the payload part of the buffers off into its own array shared between IPv4 and IPv6. As well as saving a little memory, this allows the payload buffers to be neatly page aligned. With the buffers merged, udp[46]_l2_iov_sock contain exactly the same thing as each other and can also be merged. Likewise udp[46]_iov_splice can be merged together. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* udp: Explicitly set checksum in guest-bound UDP headersDavid Gibson2024-05-021-3/+4
| | | | | | | | | | | | | | | | | | For IPv4, UDP checksums are optional and can just be set to 0. udp_update_hdr4() ignores the checksum field entirely. Since these are set to 0 during startup, this works as intended for now. However, we'd like to share payload and UDP header buffers betweem IPv4 and IPv6, which does calculate UDP checksums. Therefore, for robustness, we should explicitly set the checksum field to 0 for guest-bound UDP packets. In the tap_udp4_send() slow path, however, we do allow IPv4 UDP checksums to be calculated as a compile time option. For consistency, use the same thing in the udp_update_hdr4() path, which will typically initialize to 0, but calculate a real checksum if configured to do so. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* udp: Combine initialisation of IPv4 and IPv6 iovsDavid Gibson2024-05-021-61/+53
| | | | | | | | | | We're going to introduce more sharing between the IPv4 and IPv6 buffer structures. Prepare for this by combinng the initialisation functions. While we're at it remove the misleading "sock" from the name since these initialise both tap side and sock side structures. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* udp: Split tap-bound UDP packets into multiple buffers using io vectorDavid Gibson2024-05-022-63/+49
| | | | | | | | | | | | | | | | | | | When sending to the tap device, currently we assemble the headers and payload into a single contiguous buffer. Those are described by a single struct iovec, then a batch of frames is sent to the device with tap_send_frames(). In order to better integrate the IPv4 and IPv6 paths, we want the IP header in a different buffer that might not be contiguous with the payload. To prepare for that, split the UDP packet into an iovec of buffers. We use the same split that Laurent recently introduced for TCP for convenience. This removes the last use of tap_hdr_len_(), tap_frame_base() and tap_frame_len(), so remove those too. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* test: Allow sftp via vsock-ssh in testsDavid Gibson2024-05-021-2/+4
| | | | | | | | | | During some debugging recently, I wanted to extact a file from a test guest and found it was tricky, since the ssh-over-vsock setup we had didn't allow sftp/scp. We can fix this by adding a line to the guest side sshd config from mbuto. While we're there correct an inaccurate comment. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tcp: Update tap specific header too in tcp_fill_headers[46]()David Gibson2024-05-021-14/+14
| | | | | | | | | | | | | | tcp_fill_headers[46]() fill most of the headers, but the tap specific header (the frame length for qemu sockets) is filled in afterwards. Filling this as well: * Removes a little redundancy between the tcp_send_flag() and tcp_data_to_tap() path * Makes calculation of the correct length a little easier * Removes the now misleadingly named 'vnet_len' variable in tcp_send_flag() Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* iov: Helper macro to construct iovs covering existing variables or fieldsDavid Gibson2024-05-024-21/+16
| | | | | | | | | | | Laurent's recent changes mean we use IO vectors much more heavily in the TCP code. In many of those cases, and few others around the code base, individual iovs of these vectors are constructed to exactly cover existing variables or fields. We can make initializing such iovs shorter and clearer with a macro for the purpose. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tap, tcp: (Re-)abstract TAP specific header handlingDavid Gibson2024-05-022-25/+42
| | | | | | | | | | | | | | | Recent changes to the TCP code (reworking of the buffer handling) have meant that it now (again) deals explicitly with the MODE_PASST specific vnet_len field, instead of using the (partial) abstractions provided by the tap layer. The abstractions we had don't work for the new TCP structure, so make some new ones that do: tap_hdr_iov() which constructs an iovec suitable for containing (just) the TAP specific header and tap_hdr_update() which updates it as necessary per-packet. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
* tcp: Simplify packet length calculation when preparing headersDavid Gibson2024-05-021-16/+10
| | | | | | | | | tcp_fill_headers[46]() compute the L3 packet length from the L4 packet length, then their caller tcp_l2_buf_fill_headers() converts it back to the L4 packet length. We can just use the L4 length throughout. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>eewwee Signed-off-by: Stefano Brivio <sbrivio@redhat.com>