Ralph Boehme [Thu, 16 Nov 2023 09:50:32 +0000 (10:50 +0100)]
smbd: fix close order of base_fsp and stream_fsp in smb_fname_fsp_destructor()
VFS modules like streams_xattr use the function fsp_is_alternate_stream() on the
fsp to determine in an fsp is a stream, eg in streams_xattr_close(). If
fspo->base_fsp is arlready set to NULL, this won't work anymore.
Signed-off-by: Ralph Boehme <slow@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Thu Nov 16 18:31:17 UTC 2023 on atb-devel-224
Ralph Boehme [Wed, 20 Sep 2023 21:21:44 +0000 (14:21 -0700)]
s3: smbd: Ignore fstat() error on deleted stream in fd_close().
In the fd_close() fsp->fsp_flags.fstat_before_close code path.
If this is a stream and delete-on-close was set, the
backing object (an xattr from streams_xattr) might
already be deleted so fstat() fails with
NT_STATUS_NOT_FOUND. So if fsp refers to a stream we
ignore the error and only bail for normal files where
an fstat() should still work. NB. We cannot use
fsp_is_alternate_stream(fsp) for this as the base_fsp
has already been closed at this point and so the value
fsp_is_alternate_stream() checks for is already NULL.
Signed-off-by: Ralph Boehme <slow@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Volker Lendecke <vl@samba.org>
Autobuild-Date(master): Tue Oct 10 09:39:27 UTC 2023 on atb-devel-224
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 97e4aab1a6e2feda7c6c6fdeaa7c3e1818c55566)
Autobuild-User(v4-18-test): Jule Anger <janger@samba.org>
Autobuild-Date(v4-18-test): Mon Oct 23 09:52:22 UTC 2023 on atb-devel-224
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 70586061128f90afa33f25e104d4570a1cf778db)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 498542be0bbf4f26558573c1f87b77b8e3509371)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 7f8b15faa76d05023c987fac2c4c31f9ac61bb47)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 0c329a0fda37d87ed737e4b579b6d04ec907604c)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 3be190dcf7153e479383f7f3d29ddca43fe121b8)
Signed-off-by: Michael Adam <obnox@samba.org> Reviewed-by: Christof Schmitt <christof.schmitt@us.ibm.com> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Autobuild-User(master): Andrew Bartlett <abartlet@samba.org>
Autobuild-Date(master): Tue Oct 17 04:16:29 UTC 2023 on atb-devel-224
Signed-off-by: Martin Schwenke <mschwenke@ddn.com> Reviewed-by: Ralph Boehme <slow@samba.org>
Autobuild-User(master): Martin Schwenke <martins@samba.org>
Autobuild-Date(master): Thu Sep 21 00:46:50 UTC 2023 on atb-devel-224
Andrew Bartlett [Tue, 12 Sep 2023 00:28:49 +0000 (12:28 +1200)]
CVE-2023-42670 s3-rpc_server: Strictly refuse to start RPC servers in conflict with AD DC
Just as we refuse to start NETLOGON except on the DC, we must refuse
to start all of the RPC services that are provided by the AD DC.
Most critically of course this applies to netlogon, lsa and samr.
This avoids the supression of these services being the result of a
runtime epmapper lookup, as if that fails these services can disrupt
service to end users by listening on the same socket as the AD DC
servers.
Andrew Bartlett [Tue, 12 Sep 2023 07:01:03 +0000 (19:01 +1200)]
CVE-2023-42669 s3-rpc_server: Disable rpcecho for consistency with the AD DC
The rpcecho server in source3 does have samba the sleep() feature that
the s4 version has, but the task architecture is different, so there
is not the same impact. Hoever equally this is not something that
should be enabled on production builds of Samba, so restrict to
selftest builds.
Andrew Bartlett [Tue, 12 Sep 2023 06:59:44 +0000 (18:59 +1200)]
CVE-2023-42669 s4-rpc_server: Disable rpcecho server by default
The rpcecho server is useful in development and testing, but should never
have been allowed into production, as it includes the facility to
do a blocking sleep() in the single-threaded rpc worker.
Andrew Bartlett [Tue, 8 Aug 2023 05:58:27 +0000 (17:58 +1200)]
CVE-2023-4154: Unimplement the original DirSync behaviour without LDAP_DIRSYNC_OBJECT_SECURITY
This makes LDAP_DIRSYNC_OBJECT_SECURITY the only behaviour provided by
Samba.
Having a second access control system withing the LDAP stack is unsafe
and this layer is incomplete.
The current system gives all accounts that have been given the
GUID_DRS_GET_CHANGES extended right SYSTEM access. Currently in Samba
this equates to full access to passwords as well as "RODC Filtered
attributes" (often used with confidential attributes).
Rather than attempting to correctly filter for secrets (passwords) and
these filtered attributes, as well as preventing search expressions for
both, we leave this complexity to the acl_read module which has this
facility already well tested.
The implication is that callers will only see and filter by attribute
in DirSync that they could without DirSync.
The aim here is to document the expected (even if not implemented)
SEARCH_FLAG_RODC_ATTRIBUTE vs SEARCH_FLAG_CONFIDENTIAL, behaviour, so
that any change once CVE-2023-4154 is fixed can be noted.
Andrew Bartlett [Tue, 8 Aug 2023 02:30:19 +0000 (14:30 +1200)]
CVE-2023-4154 dsdb/tests: Add test for SEARCH_FLAG_RODC_ATTRIBUTE behaviour
SEARCH_FLAG_RODC_ATTRIBUTE should be like SEARCH_FLAG_CONFIDENTIAL,
but for DirSync and DRS replication. Accounts with
GUID_DRS_GET_CHANGES rights should not be able to read this
attribute.
Andrew Bartlett [Mon, 7 Aug 2023 23:18:46 +0000 (11:18 +1200)]
CVE-2023-4154 dsdb/tests: Speed up DirSync test by only checking positive matches once
When we (expect to) get back a result, do not waste time against a potentially
slow server confirming we also get back results for all the other attribute
combinations.
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 2c02378029fff6636b8f19e45af78b265f2210ed)
CVE-2023-4154 libcli/security: prepare security_descriptor_acl_add() to place the ace at a position
Often it is important to insert an ace at a specific position in the
ACL. As a default we still append by default by using -1, which is the
generic version of passing the number of existing aces.
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit c3cb915a67aff6739b72b86d7d139609df309ada)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 9d8ff0d1e0b2ba7c84af36e1931f5bc99902a44b)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 4627997ddae44265ad35b3234232eb74458c6c34)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 9ea06aaf9f57e3c7094553d9ac40fb73057a9b74)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit a1109a9bf12e020636b8d66fc54984aac58bfe6b)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 8411e6d302e25d10f1035ebbdcbde7308566e930)
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 8b4e6f7b3fb8018cb64deef9b8e1cbc2e5ba12cf)
Signed-off-by: Andreas Schneider <asn@samba.org> Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
(cherry picked from commit b29793ffdee5d9b9c1c05830622e80f7faec7670)
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 2e5d08c908b3fa48b9b374279a331061cb77bce3)
Signed-off-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
(cherry picked from commit 82d2ec786f7e75ff6f34eb3357964345b10de091)
Ralph Boehme [Tue, 1 Aug 2023 11:04:36 +0000 (13:04 +0200)]
CVE-2023-4091: smbd: use open_access_mask for access check in open_file()
If the client requested FILE_OVERWRITE[_IF], we're implicitly adding
FILE_WRITE_DATA to the open_access_mask in open_file_ntcreate(), but for the
access check we're using access_mask which doesn't contain the additional
right, which means we can end up truncating a file for which the user has
only read-only access via an SD.
Andrew Bartlett [Tue, 12 Sep 2023 00:28:49 +0000 (12:28 +1200)]
CVE-2023-42670 s3-rpc_server: Strictly refuse to start RPC servers in conflict with AD DC
Just as we refuse to start NETLOGON except on the DC, we must refuse
to start all of the RPC services that are provided by the AD DC.
Most critically of course this applies to netlogon, lsa and samr.
This avoids the supression of these services being the result of a
runtime epmapper lookup, as if that fails these services can disrupt
service to end users by listening on the same socket as the AD DC
servers.
Andrew Bartlett [Tue, 12 Sep 2023 07:01:03 +0000 (19:01 +1200)]
CVE-2023-42669 s3-rpc_server: Disable rpcecho for consistency with the AD DC
The rpcecho server in source3 does have samba the sleep() feature that
the s4 version has, but the task architecture is different, so there
is not the same impact. Hoever equally this is not something that
should be enabled on production builds of Samba, so restrict to
selftest builds.
Andrew Bartlett [Tue, 12 Sep 2023 06:59:44 +0000 (18:59 +1200)]
CVE-2023-42669 s4-rpc_server: Disable rpcecho server by default
The rpcecho server is useful in development and testing, but should never
have been allowed into production, as it includes the facility to
do a blocking sleep() in the single-threaded rpc worker.
Andrew Bartlett [Tue, 8 Aug 2023 05:58:27 +0000 (17:58 +1200)]
CVE-2023-4154: Unimplement the original DirSync behaviour without LDAP_DIRSYNC_OBJECT_SECURITY
This makes LDAP_DIRSYNC_OBJECT_SECURITY the only behaviour provided by
Samba.
Having a second access control system withing the LDAP stack is unsafe
and this layer is incomplete.
The current system gives all accounts that have been given the
GUID_DRS_GET_CHANGES extended right SYSTEM access. Currently in Samba
this equates to full access to passwords as well as "RODC Filtered
attributes" (often used with confidential attributes).
Rather than attempting to correctly filter for secrets (passwords) and
these filtered attributes, as well as preventing search expressions for
both, we leave this complexity to the acl_read module which has this
facility already well tested.
The implication is that callers will only see and filter by attribute
in DirSync that they could without DirSync.
The aim here is to document the expected (even if not implemented)
SEARCH_FLAG_RODC_ATTRIBUTE vs SEARCH_FLAG_CONFIDENTIAL, behaviour, so
that any change once CVE-2023-4154 is fixed can be noted.
Andrew Bartlett [Tue, 8 Aug 2023 02:30:19 +0000 (14:30 +1200)]
CVE-2023-4154 dsdb/tests: Add test for SEARCH_FLAG_RODC_ATTRIBUTE behaviour
SEARCH_FLAG_RODC_ATTRIBUTE should be like SEARCH_FLAG_CONFIDENTIAL,
but for DirSync and DRS replication. Accounts with
GUID_DRS_GET_CHANGES rights should not be able to read this
attribute.
Andrew Bartlett [Mon, 7 Aug 2023 23:18:46 +0000 (11:18 +1200)]
CVE-2023-4154 dsdb/tests: Speed up DirSync test by only checking positive matches once
When we (expect to) get back a result, do not waste time against a potentially
slow server confirming we also get back results for all the other attribute
combinations.
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 2c02378029fff6636b8f19e45af78b265f2210ed)
CVE-2023-4154 libcli/security: prepare security_descriptor_acl_add() to place the ace at a position
Often it is important to insert an ace at a specific position in the
ACL. As a default we still append by default by using -1, which is the
generic version of passing the number of existing aces.
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit c3cb915a67aff6739b72b86d7d139609df309ada)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 9d8ff0d1e0b2ba7c84af36e1931f5bc99902a44b)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 4627997ddae44265ad35b3234232eb74458c6c34)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 9ea06aaf9f57e3c7094553d9ac40fb73057a9b74)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit a1109a9bf12e020636b8d66fc54984aac58bfe6b)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
(cherry picked from commit 8411e6d302e25d10f1035ebbdcbde7308566e930)
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 8b4e6f7b3fb8018cb64deef9b8e1cbc2e5ba12cf)
Signed-off-by: Andreas Schneider <asn@samba.org> Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
(cherry picked from commit b29793ffdee5d9b9c1c05830622e80f7faec7670)
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 2e5d08c908b3fa48b9b374279a331061cb77bce3)
Signed-off-by: Andrew Bartlett <abartlet@samba.org> Reviewed-by: Joseph Sutton <josephsutton@catalyst.net.nz>
(cherry picked from commit 82d2ec786f7e75ff6f34eb3357964345b10de091)
Ralph Boehme [Tue, 1 Aug 2023 11:04:36 +0000 (13:04 +0200)]
CVE-2023-4091: smbd: use open_access_mask for access check in open_file()
If the client requested FILE_OVERWRITE[_IF], we're implicitly adding
FILE_WRITE_DATA to the open_access_mask in open_file_ntcreate(), but for the
access check we're using access_mask which doesn't contain the additional
right, which means we can end up truncating a file for which the user has
only read-only access via an SD.
Joseph Sutton [Mon, 4 Sep 2023 01:20:34 +0000 (13:20 +1200)]
s4:kdc: Add correct Asserted Identity SID in response to an S4U2Self request
I’m not sure exactly how this check was supposed to work. But in any
case, within fast_unwrap_request() the Heimdal KDC replaces the outer
padata with the padata from the inner FAST request. Hence, this check
does not accomplish anything useful: at no point should the KDC plugin
see the outer padata.
A couple of unwanted consequences resulted from this check. One was that
a client who sent empty FX‐FAST padata within the inner FAST request
would receive the *Authentication Authority* Asserted Identity SID
instead of the *Service* Asserted Identity SID. Another consequence was
that a client could in the same manner bypass the restriction on
performing S4U2Self with an RODC‐issued TGT.
Overall, samba_wdc_is_s4u2self_req() is somewhat of a hack. But the
Heimdal plugin API gives us nothing better to work with.
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 5c580dbdb3e6a70c8d2f5059e2b7293a7e780414)
Joseph Sutton [Thu, 16 Mar 2023 20:16:17 +0000 (09:16 +1300)]
s4:kdc: Avoid copying data if not needed
krb5_pac_add_buffer() makes its own copy of the data we pass in. We
don't need to make yet another copy.
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit fa901e7346d36ae64a7ceab5dcf76bc210a67c93)
Joseph Sutton [Thu, 16 Mar 2023 20:25:52 +0000 (09:25 +1300)]
s4:kdc: Don't pass a NULL pointer into krb5_pac_add_buffer()
Heimdal contains an assertion that the data pointer is not NULL. We need
to pass in a pointer to some dummy data instead.
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 47ef49fd91f050ce4a79a8471b3e66c808f48752)
Signed-off-by: Jeremy Allison <jra@samba.org> Reviewed-by: Ralph Boehme <slow@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Wed Sep 20 02:43:18 UTC 2023 on atb-devel-224
nsswitch/wb_common.c: fix socket fd and memory leaks of global state
When we are called in wb_atfork_child() or winbind_destructor(),
wb_thread_ctx_destructor() is not called for the global state
of the current nor any other thread, which means we would
leak the related memory and socket fds.
Now we maintain a global list protected by a global mutex.
We traverse the list and close all socket fds, which are no
longer used (winbind_destructor) or no longer valid in the
current process (wb_atfork_child), in addition we 'autofree'
the ones, which are only visible internally as global (per thread)
context.
Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl> Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Stefan Metzmacher <metze@samba.org>
Autobuild-Date(master): Thu Sep 14 18:53:07 UTC 2023 on atb-devel-224
nsswitch/wb_common.c: don't operate on a stale wb_global_ctx.key
If nss_winbind is loaded into a process that uses fork multiple times
without any further calls into nss_winbind, wb_atfork_child handler
was using a wb_global_ctx.key that was no longer registered in the
pthread library, so we operated on a slot that was potentially
reused by other libraries or the main application. Which is likely
to cause memory corruption.
So we better don't call pthread_key_delete() in wb_atfork_child().
Reported-by: Krzysztof Piotr Oledzki <ole@ans.pl> Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl> Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit 91b30a7261e6455d3a4f31728c23e4849e3945b9)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit 836823e5047d0eb18e66707386ba03b812adfaf8)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit 4faf806412c4408db25448b1f67c09359ec2f81f)
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit 62af25d44e542548d8cdecb061a6001e0071ee76)
Ralph Boehme [Tue, 29 Aug 2023 14:14:38 +0000 (16:14 +0200)]
mdssvc: better support for search with mdfind from Macs
When searching Samba via Spotlight from a Mac with mdfind, only 50 results are
returned.
It seems the changes for bug #15342 where one step in the right
direction. There, a status indicator meaning "search is still being processed"
was implemented, returning a special status indicator (0x23) in a response, when
the query was still running in the backend, eg Elasticsearch, and we haven't got
any result when when the Mac already comes along asking for results of a query.
Turns out, we should also return 0x23, ie "search is still being processed" when
we have some initial search results from the backend. Otherwise mdfind will stop
querying for more results. It works in Finder, as the Finder by default employs
a "live" search where it just keeps polling for more results even after the
server returned an empty result set. The Finder just keeps on querying in some
interval, typically 4 seconds, and a Mac server Spotlight server might return
new results if new files where created that match the query, hence "live"
search.
Signed-off-by: Ralph Boehme <slow@samba.org> Reviewed-by: Noel Power <noel.power@suse.com>
Autobuild-User(master): Ralph Böhme <slow@samba.org>
Autobuild-Date(master): Wed Aug 30 10:51:40 UTC 2023 on atb-devel-224
MikeLiu [Tue, 22 Aug 2023 02:01:14 +0000 (10:01 +0800)]
vfs_aio_pthread: use SMB_VFS_NEXT_OPENAT() in aio_pthread_openat_fn()
1. Set 'aio_allow_open' to false if fsp->fsp_flags.is_pathref
2. Move !(how->flags & O_CREAT) and !(how->flags & O_EXCL) up and set 'aio_allow_open' to false
3. Use SMB_VFS_NEXT_OPENAT() instead of openat() for disable async opens case.
Signed-off-by: MikeLiu <mikeliu@qnap.com> Reviewed-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Tue Aug 22 17:44:00 UTC 2023 on atb-devel-224
Autobuild-User(v4-18-test): Jule Anger <janger@samba.org>
Autobuild-Date(v4-18-test): Mon Sep 4 09:49:30 UTC 2023 on atb-devel-224
Signed-off-by: Jeremy Allison <jra@samba.org> Reviewed-by: Ralph Boehme <slow@samba.org>
Autobuild-User(master): Ralph Böhme <slow@samba.org>
Autobuild-Date(master): Thu Jul 27 10:52:50 UTC 2023 on atb-devel-224
Martin Schwenke [Tue, 15 Aug 2023 02:34:20 +0000 (12:34 +1000)]
ctdb-common: Set immediate mode for pcap capture
Fix a problem where ctdb_killtcp (almost always) fails to capture
packets with --enable-pcap and libpcap ≥ 1.9.1. The problem is due to
a gradual change in libpcap semantics when using
pcap_get_selectable_fd(3PCAP) to get a file descriptor and then using
that file descriptor in non-blocking mode.
pcap_set_immediate_mode(3PCAP) says:
pcap_set_immediate_mode() sets whether immediate mode should be set
on a capture handle when the handle is activated. In immediate
mode, packets are always delivered as soon as they arrive, with no
buffering.
and
On Linux, with previous releases of libpcap, capture devices are
always in immediate mode; however, in 1.5.0 and later, they are, by
default, not in immediate mode, so if pcap_set_immediate_mode() is
available, it should be used.
However, it wasn't until libpcap commit 2ade7676101366983bd4f86bc039ffd25da8c126 (before libpcap 1.9.1) that
it became a requirement to use pcap_set_immediate_mode(), even with a
timeout of 0.