- 18 Jan, 2020 3 commits
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Aleksa Sarai authored
Now that we have new LOOKUP flags, we should document them in the relevant path-walking documentation. And now that we've settled on a common name for nd_jump_link() style symlinks ("magic links"), use that term where magic-link semantics are described. Signed-off-by:Aleksa Sarai <cyphar@cyphar.com> Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk>
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Aleksa Sarai authored
Test all of the various openat2(2) flags. A small stress-test of a symlink-rename attack is included to show that the protections against ".."-based attacks are sufficient. The main things these self-tests are enforcing are: * The struct+usize ABI for openat2(2) and copy_struct_from_user() to ensure that upgrades will be handled gracefully (in addition, ensuring that misaligned structures are also handled correctly). * The -EINVAL checks for openat2(2) are all correctly handled to avoid userspace passing unknown or conflicting flag sets (most importantly, ensuring that invalid flag combinations are checked). * All of the RESOLVE_* semantics (including errno values) are correctly handled with various combinations of paths and flags. * RESOLVE_IN_ROOT correctly protects against the symlink rename(2) attack that has been responsible for several CVEs (and likely will be responsible for several more). Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: -
Aleksa Sarai authored
/* Background. */ For a very long time, extending openat(2) with new features has been incredibly frustrating. This stems from the fact that openat(2) is possibly the most famous counter-example to the mantra "don't silently accept garbage from userspace" -- it doesn't check whether unknown flags are present[1]. This means that (generally) the addition of new flags to openat(2) has been fraught with backwards-compatibility issues (O_TMPFILE has to be defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old kernels gave errors, since it's insecure to silently ignore the flag[2]). All new security-related flags therefore have a tough road to being added to openat(2). Userspace also has a hard time figuring out whether a particular flag is supported on a particular kernel. While it is now possible with contemporary kernels (thanks to [3]), older kernels will expose unknown flag bits through fcntl(F_GETFL). Giving a clear -EINVAL during openat(2) time matches modern syscall designs and is far more fool-proof. In addition, the newly-added path resolution restriction LOOKUP flags (which we would like to expose to user-space) don't feel related to the pre-existing O_* flag set -- they affect all components of path lookup. We'd therefore like to add a new flag argument. Adding a new syscall allows us to finally fix the flag-ignoring problem, and we can make it extensible enough so that we will hopefully never need an openat3(2). /* Syscall Prototype. */ /* * open_how is an extensible structure (similar in interface to * clone3(2) or sched_setattr(2)). The size parameter must be set to * sizeof(struct open_how), to allow for future extensions. All future * extensions will be appended to open_how, with their zero value * acting as a no-op default. */ struct open_how { /* ... */ }; int openat2(int dfd, const char *pathname, struct open_how *how, size_t size); /* Description. */ The initial version of 'struct open_how' contains the following fields: flags Used to specify openat(2)-style flags. However, any unknown flag bits or otherwise incorrect flag combinations (like O_PATH|O_RDWR) will result in -EINVAL. In addition, this field is 64-bits wide to allow for more O_ flags than currently permitted with openat(2). mode The file mode for O_CREAT or O_TMPFILE. Must be set to zero if flags does not contain O_CREAT or O_TMPFILE. resolve Restrict path resolution (in contrast to O_* flags they affect all path components). The current set of flags are as follows (at the moment, all of the RESOLVE_ flags are implemented as just passing the corresponding LOOKUP_ flag). RESOLVE_NO_XDEV => LOOKUP_NO_XDEV RESOLVE_NO_SYMLINKS => LOOKUP_NO_SYMLINKS RESOLVE_NO_MAGICLINKS => LOOKUP_NO_MAGICLINKS RESOLVE_BENEATH => LOOKUP_BENEATH RESOLVE_IN_ROOT => LOOKUP_IN_ROOT open_how does not contain an embedded size field, because it is of little benefit (userspace can figure out the kernel open_how size at runtime fairly easily without it). It also only contains u64s (even though ->mode arguably should be a u16) to avoid having padding fields which are never used in the future. Note that as a result of the new how->flags handling, O_PATH|O_TMPFILE is no longer permitted for openat(2). As far as I can tell, this has always been a bug and appears to not be used by userspace (and I've not seen any problems on my machines by disallowing it). If it turns out this breaks something, we can special-case it and only permit it for openat(2) but not openat2(2). After input from Florian Weimer, the new open_how and flag definitions are inside a separate header from uapi/linux/fcntl.h, to avoid problems that glibc has with importing that header. /* Testing. */ In a follow-up patch there are over 200 selftests which ensure that this syscall has the correct semantics and will correctly handle several attack scenarios. In addition, I've written a userspace library[4] which provides convenient wrappers around openat2(RESOLVE_IN_ROOT) (this is necessary because no other syscalls support RESOLVE_IN_ROOT, and thus lots of care must be taken when using RESOLVE_IN_ROOT'd file descriptors with other syscalls). During the development of this patch, I've run numerous verification tests using libpathrs (showing that the API is reasonably usable by userspace). /* Future Work. */ Additional RESOLVE_ flags have been suggested during the review period. These can be easily implemented separately (such as blocking auto-mount during resolution). Furthermore, there are some other proposed changes to the openat(2) interface (the most obvious example is magic-link hardening[5]) which would be a good opportunity to add a way for userspace to restrict how O_PATH file descriptors can be re-opened. Another possible avenue of future work would be some kind of CHECK_FIELDS[6] flag which causes the kernel to indicate to userspace which openat2(2) flags and fields are supported by the current kernel (to avoid userspace having to go through several guesses to figure it out). [1]: https://lwn.net/Articles/588444/ [2]: https://lore.kernel.org/lkml/CA+55aFyyxJL1LyXZeBsf2ypriraj5ut1XkNDsunRBqgVjZU_6Q@mail.gmail.com [3]: commit 629e014b ("fs: completely ignore unknown open flags") [4]: https://sourceware.org/bugzilla/show_bug.cgi?id=17523 [5]: https://lore.kernel.org/lkml/20190930183316.10190-2-cyphar@cyphar.com/ [6]: https://youtu.be/ggD-eb3yPVsSuggested-by:Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by:
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- 09 Dec, 2019 10 commits
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Aleksa Sarai authored
Allow LOOKUP_BENEATH and LOOKUP_IN_ROOT to safely permit ".." resolution (in the case of LOOKUP_BENEATH the resolution will still fail if ".." resolution would resolve a path outside of the root -- while LOOKUP_IN_ROOT will chroot(2)-style scope it). Magic-link jumps are still disallowed entirely[*]. As Jann explains[1,2], the need for this patch (and the original no-".." restriction) is explained by observing there is a fairly easy-to-exploit race condition with chroot(2) (and thus by extension LOOKUP_IN_ROOT and LOOKUP_BENEATH if ".." is allowed) where a rename(2) of a path can be used to "skip over" nd->root and thus escape to the filesystem above nd->root. thread1 [attacker]: for (;;) renameat2(AT_FDCWD, "/a/b/c", AT_FDCWD, "/a/d", RENAME_EXCHANGE); thread2 [victim]: for (;;) openat2(dirb, "b/c/../../etc/shadow", { .flags = O_PATH, .resolve = RESOLVE_IN_ROOT } ); With fairly significant regularity, thread2 will resolve to "/etc/shadow" rather than "/a/b/etc/shadow". There is also a similar (though somewhat more privileged) attack using MS_MOVE. With this patch, such cases will be detected *during* ".." resolution and will return -EAGAIN for userspace to decide to either retry or abort the lookup. It should be noted that ".." is the weak point of chroot(2) -- walking *into* a subdirectory tautologically cannot result in you walking *outside* nd->root (except through a bind-mount or magic-link). There is also no other way for a directory's parent to change (which is the primary worry with ".." resolution here) other than a rename or MS_MOVE. The primary reason for deferring to userspace with -EAGAIN is that an in-kernel retry loop (or doing a path_is_under() check after re-taking the relevant seqlocks) can become unreasonably expensive on machines with lots of VFS activity (nfsd can cause lots of rename_lock updates). Thus it should be up to userspace how many times they wish to retry the lookup -- the selftests for this attack indicate that there is a ~35% chance of the lookup succeeding on the first try even with an attacker thrashing rename_lock. A variant of the above attack is included in the selftests for openat2(2) later in this patch series. I've run this test on several machines for several days and no instances of a breakout were detected. While this is not concrete proof that this is safe, when combined with the above argument it should lend some trustworthiness to this construction. [*] It may be acceptable in the future to do a path_is_under() check for magic-links after they are resolved. However this seems unlikely to be a feature that people *really* need -- it can be added later if it turns out a lot of people want it. [1]: https://lore.kernel.org/lkml/CAG48ez1jzNvxB+bfOBnERFGp=oMM0vHWuLD6EULmne3R6xa53w@mail.gmail.com/ [2]: https://lore.kernel.org/lkml/CAG48ez30WJhbsro2HOc_DR7V91M+hNFzBP5ogRMZaxbAORvqzg@mail.gmail.com/ Cc: Christian Brauner <christian.brauner@ubuntu.com> Suggested-by:Jann Horn <jannh@google.com> Suggested-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Aleksa Sarai authored
/* Background. */ Container runtimes or other administrative management processes will often interact with root filesystems while in the host mount namespace, because the cost of doing a chroot(2) on every operation is too prohibitive (especially in Go, which cannot safely use vfork). However, a malicious program can trick the management process into doing operations on files outside of the root filesystem through careful crafting of symlinks. Most programs that need this feature have attempted to make this process safe, by doing all of the path resolution in userspace (with symlinks being scoped to the root of the malicious root filesystem). Unfortunately, this method is prone to foot-guns and usually such implementations have subtle security bugs. Thus, what userspace needs is a way to resolve a path as though it were in a chroot(2) -- with all absolute symlinks being resolved relative to the dirfd root (and ".." components being stuck under the dirfd root). It is much simpler and more straight-forward to provide this functionality in-kernel (because it can be done far more cheaply and correctly). More classical applications that also have this problem (which have their own potentially buggy userspace path sanitisation code) include web servers, archive extraction tools, network file servers, and so on. /* Userspace API. */ LOOKUP_IN_ROOT will be exposed to userspace through openat2(2). /* Semantics. */ Unlike most other LOOKUP flags (most notably LOOKUP_FOLLOW), LOOKUP_IN_ROOT applies to all components of the path. With LOOKUP_IN_ROOT, any path component which attempts to cross the starting point of the pathname lookup (the dirfd passed to openat) will remain at the starting point. Thus, all absolute paths and symlinks will be scoped within the starting point. There is a slight change in behaviour regarding pathnames -- if the pathname is absolute then the dirfd is still used as the root of resolution of LOOKUP_IN_ROOT is specified (this is to avoid obvious foot-guns, at the cost of a minor API inconsistency). As with LOOKUP_BENEATH, Jann's security concern about ".."[1] applies to LOOKUP_IN_ROOT -- therefore ".." resolution is blocked. This restriction will be lifted in a future patch, but requires more work to ensure that permitting ".." is done safely. Magic-link jumps are also blocked, because they can beam the path lookup across the starting point. It would be possible to detect and block only the "bad" crossings with path_is_under() checks, but it's unclear whether it makes sense to permit magic-links at all. However, userspace is recommended to pass LOOKUP_NO_MAGICLINKS if they want to ensure that magic-link crossing is entirely disabled. /* Testing. */ LOOKUP_IN_ROOT is tested as part of the openat2(2) selftests. [1]: https://lore.kernel.org/lkml/CAG48ez1jzNvxB+bfOBnERFGp=oMM0vHWuLD6EULmne3R6xa53w@mail.gmail.com/ Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by:
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Aleksa Sarai authored
/* Background. */ There are many circumstances when userspace wants to resolve a path and ensure that it doesn't go outside of a particular root directory during resolution. Obvious examples include archive extraction tools, as well as other security-conscious userspace programs. FreeBSD spun out O_BENEATH from their Capsicum project[1,2], so it also seems reasonable to implement similar functionality for Linux. This is part of a refresh of Al's AT_NO_JUMPS patchset[3] (which was a variation on David Drysdale's O_BENEATH patchset[4], which in turn was based on the Capsicum project[5]). /* Userspace API. */ LOOKUP_BENEATH will be exposed to userspace through openat2(2). /* Semantics. */ Unlike most other LOOKUP flags (most notably LOOKUP_FOLLOW), LOOKUP_BENEATH applies to all components of the path. With LOOKUP_BENEATH, any path component which attempts to "escape" the starting point of the filesystem lookup (the dirfd passed to openat) will yield -EXDEV. Thus, all absolute paths and symlinks are disallowed. Due to a security concern brought up by Jann[6], any ".." path components are also blocked. This restriction will be lifted in a future patch, but requires more work to ensure that permitting ".." is done safely. Magic-link jumps are also blocked, because they can beam the path lookup across the starting point. It would be possible to detect and block only the "bad" crossings with path_is_under() checks, but it's unclear whether it makes sense to permit magic-links at all. However, userspace is recommended to pass LOOKUP_NO_MAGICLINKS if they want to ensure that magic-link crossing is entirely disabled. /* Testing. */ LOOKUP_BENEATH is tested as part of the openat2(2) selftests. [1]: https://reviews.freebsd.org/D2808 [2]: https://reviews.freebsd.org/D17547 [3]: https://lore.kernel.org/lkml/20170429220414.GT29622@ZenIV.linux.org.uk/ [4]: https://lore.kernel.org/lkml/1415094884-18349-1-git-send-email-drysdale@google.com/ [5]: https://lore.kernel.org/lkml/1404124096-21445-1-git-send-email-drysdale@google.com/ [6]: https://lore.kernel.org/lkml/CAG48ez1jzNvxB+bfOBnERFGp=oMM0vHWuLD6EULmne3R6xa53w@mail.gmail.com/ Cc: Christian Brauner <christian.brauner@ubuntu.com> Suggested-by:
David Drysdale <drysdale@google.com> Suggested-by:
Andy Lutomirski <luto@kernel.org> Suggested-by:
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Aleksa Sarai authored
/* Background. */ The need to contain path operations within a mountpoint has been a long-standing usecase that userspace has historically implemented manually with liberal usage of stat(). find, rsync, tar and many other programs implement these semantics -- but it'd be much simpler to have a fool-proof way of refusing to open a path if it crosses a mountpoint. This is part of a refresh of Al's AT_NO_JUMPS patchset[1] (which was a variation on David Drysdale's O_BENEATH patchset[2], which in turn was based on the Capsicum project[3]). /* Userspace API. */ LOOKUP_NO_XDEV will be exposed to userspace through openat2(2). /* Semantics. */ Unlike most other LOOKUP flags (most notably LOOKUP_FOLLOW), LOOKUP_NO_XDEV applies to all components of the path. With LOOKUP_NO_XDEV, any path component which crosses a mount-point during path resolution (including "..") will yield an -EXDEV. Absolute paths, absolute symlinks, and magic-links will only yield an -EXDEV if the jump involved changing mount-points. /* Testing. */ LOOKUP_NO_XDEV is tested as part of the openat2(2) selftests. [1]: https://lore.kernel.org/lkml/20170429220414.GT29622@ZenIV.linux.org.uk/ [2]: https://lore.kernel.org/lkml/1415094884-18349-1-git-send-email-drysdale@google.com/ [3]: https://lore.kernel.org/lkml/1404124096-21445-1-git-send-email-drysdale@google.com/ Cc: Christian Brauner <christian.brauner@ubuntu.com> Suggested-by:
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Aleksa Sarai authored
/* Background. */ There has always been a special class of symlink-like objects in procfs (and a few other pseudo-filesystems) which allow for non-lexical resolution of paths using nd_jump_link(). These "magic-links" do not follow traditional mount namespace boundaries, and have been used consistently in container escape attacks because they can be used to trick unsuspecting privileged processes into resolving unexpected paths. It is also non-trivial for userspace to unambiguously avoid resolving magic-links, because they do not have a reliable indication that they are a magic-link (in order to verify them you'd have to manually open the path given by readlink(2) and then verify that the two file descriptors reference the same underlying file, which is plagued with possible race conditions or supplementary attack scenarios). It would therefore be very helpful for userspace to be able to avoid these symlinks easily, thus hopefully removing a tool from attackers' toolboxes. This is part of a refresh of Al's AT_NO_JUMPS patchset[1] (which was a variation on David Drysdale's O_BENEATH patchset[2], which in turn was based on the Capsicum project[3]). /* Userspace API. */ LOOKUP_NO_MAGICLINKS will be exposed to userspace through openat2(2). /* Semantics. */ Unlike most other LOOKUP flags (most notably LOOKUP_FOLLOW), LOOKUP_NO_MAGICLINKS applies to all components of the path. With LOOKUP_NO_MAGICLINKS, any magic-link path component encountered during path resolution will yield -ELOOP. The handling of ~LOOKUP_FOLLOW for a trailing magic-link is identical to LOOKUP_NO_SYMLINKS. LOOKUP_NO_SYMLINKS implies LOOKUP_NO_MAGICLINKS. /* Testing. */ LOOKUP_NO_MAGICLINKS is tested as part of the openat2(2) selftests. [1]: https://lore.kernel.org/lkml/20170429220414.GT29622@ZenIV.linux.org.uk/ [2]: https://lore.kernel.org/lkml/1415094884-18349-1-git-send-email-drysdale@google.com/ [3]: https://lore.kernel.org/lkml/1404124096-21445-1-git-send-email-drysdale@google.com/ Cc: Christian Brauner <christian.brauner@ubuntu.com> Suggested-by:
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Aleksa Sarai authored
/* Background. */ Userspace cannot easily resolve a path without resolving symlinks, and would have to manually resolve each path component with O_PATH and O_NOFOLLOW. This is clearly inefficient, and can be fairly easy to screw up (resulting in possible security bugs). Linus has mentioned that Git has a particular need for this kind of flag[1]. It also resolves a fairly long-standing perceived deficiency in O_NOFOLLOw -- that it only blocks the opening of trailing symlinks. This is part of a refresh of Al's AT_NO_JUMPS patchset[2] (which was a variation on David Drysdale's O_BENEATH patchset[3], which in turn was based on the Capsicum project[4]). /* Userspace API. */ LOOKUP_NO_SYMLINKS will be exposed to userspace through openat2(2). /* Semantics. */ Unlike most other LOOKUP flags (most notably LOOKUP_FOLLOW), LOOKUP_NO_SYMLINKS applies to all components of the path. With LOOKUP_NO_SYMLINKS, any symlink path component encountered during path resolution will yield -ELOOP. If the trailing component is a symlink (and no other components were symlinks), then O_PATH|O_NOFOLLOW will not error out and will instead provide a handle to the trailing symlink -- without resolving it. /* Testing. */ LOOKUP_NO_SYMLINKS is tested as part of the openat2(2) selftests. [1]: https://lore.kernel.org/lkml/CA+55aFyOKM7DW7+0sdDFKdZFXgptb5r1id9=Wvhd8AgSP7qjwQ@mail.gmail.com/ [2]: https://lore.kernel.org/lkml/20170429220414.GT29622@ZenIV.linux.org.uk/ [3]: https://lore.kernel.org/lkml/1415094884-18349-1-git-send-email-drysdale@google.com/ [4]: https://lore.kernel.org/lkml/1404124096-21445-1-git-send-email-drysdale@google.com/ Cc: Christian Brauner <christian.brauner@ubuntu.com> Suggested-by:
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Aleksa Sarai authored
For LOOKUP_BENEATH and LOOKUP_IN_ROOT it is necessary to ensure that set_root() is never called, and thus (for hardening purposes) it should return an error rather than permit a breakout from the root. In addition, move all of the repetitive set_root() calls to nd_jump_root(). Signed-off-by:
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Aleksa Sarai authored
In preparation for LOOKUP_NO_MAGICLINKS, it's necessary to add the ability for nd_jump_link() to return an error which the corresponding get_link() caller must propogate back up to the VFS. Suggested-by:
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Aleksa Sarai authored
ns_get_path() and ns_get_path_cb() only ever return either NULL or an ERR_PTR. It is far more idiomatic to simply return an integer, and it makes all of the callers of ns_get_path() more straightforward to read. Fixes: e149ed2b ("take the targets of /proc/*/ns/* symlinks to separate fs") Signed-off-by:
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Aleksa Sarai authored
It's over-zealous to return hard errors under RCU-walk here, given that a REF-walk will be triggered for all other cases handling ".." under RCU. The original purpose of this check was to ensure that if a rename occurs such that a directory is moved outside of the bind-mount which the resolution started in, it would be detected and blocked to avoid being able to mess with paths outside of the bind-mount. However, triggering a new REF-walk is just as effective a solution. Cc: "Eric W. Biederman" <ebiederm@xmission.com> Fixes: 397d425d ("vfs: Test for and handle paths that are unreachable from their mnt_root") Suggested-by:
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- 08 Dec, 2019 12 commits
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) More jumbo frame fixes in r8169, from Heiner Kallweit. 2) Fix bpf build in minimal configuration, from Alexei Starovoitov. 3) Use after free in slcan driver, from Jouni Hogander. 4) Flower classifier port ranges don't work properly in the HW offload case, from Yoshiki Komachi. 5) Use after free in hns3_nic_maybe_stop_tx(), from Yunsheng Lin. 6) Out of bounds access in mqprio_dump(), from Vladyslav Tarasiuk. 7) Fix flow dissection in dsa TX path, from Alexander Lobakin. 8) Stale syncookie timestampe fixes from Guillaume Nault. [ Did an evil merge to silence a warning introduced by this pull - Linus ] * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits) r8169: fix rtl_hw_jumbo_disable for RTL8168evl net_sched: validate TCA_KIND attribute in tc_chain_tmplt_add() r8169: add missing RX enabling for WoL on RTL8125 vhost/vsock: accept only packets with the right dst_cid net: phy: dp83867: fix hfs boot in rgmii mode net: ethernet: ti: cpsw: fix extra rx interrupt inet: protect against too small mtu values. gre: refetch erspan header from skb->data after pskb_may_pull() pppoe: remove redundant BUG_ON() check in pppoe_pernet tcp: Protect accesses to .ts_recent_stamp with {READ,WRITE}_ONCE() tcp: tighten acceptance of ACKs not matching a child socket tcp: fix rejected syncookies due to stale timestamps lpc_eth: kernel BUG on remove tcp: md5: fix potential overestimation of TCP option space net: sched: allow indirect blocks to bind to clsact in TC net: core: rename indirect block ingress cb function net-sysfs: Call dev_hold always in netdev_queue_add_kobject net: dsa: fix flow dissection on Tx path net/tls: Fix return values to avoid ENOTSUPP net: avoid an indirect call in ____sys_recvmsg() ... -
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds authored
Pull more SCSI updates from James Bottomley: "Eleven patches, all in drivers (no core changes) that are either minor cleanups or small fixes. They were late arriving, but still safe for -rc1" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: scsi: MAINTAINERS: Add the linux-scsi mailing list to the ISCSI entry scsi: megaraid_sas: Make poll_aen_lock static scsi: sd_zbc: Improve report zones error printout scsi: qla2xxx: Fix qla2x00_request_irqs() for MSI scsi: qla2xxx: unregister ports after GPN_FT failure scsi: qla2xxx: fix rports not being mark as lost in sync fabric scan scsi: pm80xx: Remove unused include of linux/version.h scsi: pm80xx: fix logic to break out of loop when register value is 2 or 3 scsi: scsi_transport_sas: Fix memory leak when removing devices scsi: lpfc: size cpu map by last cpu id set scsi: ibmvscsi_tgt: Remove unneeded variable rc
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git://git.samba.org/sfrench/cifs-2.6Linus Torvalds authored
Pull cifs fixes from Steve French: "Nine cifs/smb3 fixes: - one fix for stable (oops during oplock break) - two timestamp fixes including important one for updating mtime at close to avoid stale metadata caching issue on dirty files (also improves perf by using SMB2_CLOSE_FLAG_POSTQUERY_ATTRIB over the wire) - two fixes for "modefromsid" mount option for file create (now allows mode bits to be set more atomically and accurately on create by adding "sd_context" on create when modefromsid specified on mount) - two fixes for multichannel found in testing this week against different servers - two small cleanup patches" * tag '5.5-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6: smb3: improve check for when we send the security descriptor context on create smb3: fix mode passed in on create for modetosid mount option cifs: fix possible uninitialized access and race on iface_list cifs: Fix lookup of SMB connections on multichannel smb3: query attributes on file close smb3: remove unused flag passed into close functions cifs: remove redundant assignment to pointer pneg_ctxt fs: cifs: Fix atime update check vs mtime CIFS: Fix NULL-pointer dereference in smb2_push_mandatory_locks -
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds authored
Pull misc vfs cleanups from Al Viro: "No common topic, just three cleanups". * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: make __d_alloc() static fs/namespace: add __user to open_tree and move_mount syscalls fs/fnctl: fix missing __user in fcntl_rw_hint()
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git://github.com/jonmason/ntbLinus Torvalds authored
Pull NTB update from Jon Mason: "Just a simple patch to add a new Hygon Device ID to the AMD NTB device driver" * tag 'ntb-5.5' of git://github.com/jonmason/ntb: NTB: Add Hygon Device ID
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git://git.kernel.org/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds authored
Pull more input updates from Dmitry Torokhov: - fixups for Synaptics RMI4 driver - a quirk for Goodinx touchscreen on Teclast tablet - a new keycode definition for activating privacy screen feature found on a few "enterprise" laptops - updates to snvs_pwrkey driver - polling uinput device for writing (which is always allowed) now works * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: synaptics-rmi4 - don't increment rmiaddr for SMBus transfers Input: synaptics-rmi4 - re-enable IRQs in f34v7_do_reflash Input: goodix - add upside-down quirk for Teclast X89 tablet Input: add privacy screen toggle keycode Input: uinput - fix returning EPOLLOUT from uinput_poll Input: snvs_pwrkey - remove gratuitous NULL initializers Input: snvs_pwrkey - send key events for i.MX6 S, DL and Q
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git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds authored
Pull iomap fixes from Darrick Wong: "Fix a race condition and a use-after-free error: - Fix a UAF when reporting writeback errors - Fix a race condition when handling page uptodate on fragmented file with blocksize < pagesize" * tag 'iomap-5.5-merge-14' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: iomap: stop using ioend after it's been freed in iomap_finish_ioend() iomap: fix sub-page uptodate handling -
git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds authored
Pull xfs fixes from Darrick Wong: "Fix a couple of resource management errors and a hang: - fix a crash in the log setup code when log mounting fails - fix a hang when allocating space on the realtime device - fix a block leak when freeing space on the realtime device" * tag 'xfs-5.5-merge-17' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: fix mount failure crash on invalid iclog memory access xfs: don't check for AG deadlock for realtime files in bunmapi xfs: fix realtime file data space leak
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git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linuxLinus Torvalds authored
Pull orangefs update from Mike Marshall: "orangefs: posix open permission checking... Orangefs has no open, and orangefs checks file permissions on each file access. Posix requires that file permissions be checked on open and nowhere else. Orangefs-through-the-kernel needs to seem posix compliant. The VFS opens files, even if the filesystem provides no method. We can see if a file was successfully opened for read and or for write by looking at file->f_mode. When writes are flowing from the page cache, file is no longer available. We can trust the VFS to have checked file->f_mode before writing to the page cache. The mode of a file might change between when it is opened and IO commences, or it might be created with an arbitrary mode. We'll make sure we don't hit EACCES during the IO stage by using UID 0" [ This is "posixish", but not a great solution in the long run, since a proper secure network server shouldn't really trust the client like this. But proper and secure POSIX behavior requires an open method and a resulting cookie for IO of some kind, or similar. - Linus ] * tag 'for-linus-5.5-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux: orangefs: posix open permission checking...
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git://linux-nfs.org/~bfields/linuxLinus Torvalds authored
Pull nfsd updates from Bruce Fields: "This is a relatively quiet cycle for nfsd, mainly various bugfixes. Possibly most interesting is Trond's fixes for some callback races that were due to my incomplete understanding of rpc client shutdown. Unfortunately at the last minute I've started noticing a new intermittent failure to send callbacks. As the logic seems basically correct, I'm leaving Trond's patches in for now, and hope to find a fix in the next week so I don't have to revert those patches" * tag 'nfsd-5.5' of git://linux-nfs.org/~bfields/linux: (24 commits) nfsd: depend on CRYPTO_MD5 for legacy client tracking NFSD fixing possible null pointer derefering in copy offload nfsd: check for EBUSY from vfs_rmdir/vfs_unink. nfsd: Ensure CLONE persists data and metadata changes to the target file SUNRPC: Fix backchannel latency metrics nfsd: restore NFSv3 ACL support nfsd: v4 support requires CRYPTO_SHA256 nfsd: Fix cld_net->cn_tfm initialization lockd: remove __KERNEL__ ifdefs sunrpc: remove __KERNEL__ ifdefs race in exportfs_decode_fh() nfsd: Drop LIST_HEAD where the variable it declares is never used. nfsd: document callback_wq serialization of callback code nfsd: mark cb path down on unknown errors nfsd: Fix races between nfsd4_cb_release() and nfsd4_shutdown_callback() nfsd: minor 4.1 callback cleanup SUNRPC: Fix svcauth_gss_proxy_init() SUNRPC: Trace gssproxy upcall results sunrpc: fix crash when cache_head become valid before update nfsd: remove private bin2hex implementation ...
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git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds authored
Pull NFS client updates from Trond Myklebust: "Highlights include: Features: - NFSv4.2 now supports cross device offloaded copy (i.e. offloaded copy of a file from one source server to a different target server). - New RDMA tracepoints for debugging congestion control and Local Invalidate WRs. Bugfixes and cleanups - Drop the NFSv4.1 session slot if nfs4_delegreturn_prepare waits for layoutreturn - Handle bad/dead sessions correctly in nfs41_sequence_process() - Various bugfixes to the delegation return operation. - Various bugfixes pertaining to delegations that have been revoked. - Cleanups to the NFS timespec code to avoid unnecessary conversions between timespec and timespec64. - Fix unstable RDMA connections after a reconnect - Close race between waking an RDMA sender and posting a receive - Wake pending RDMA tasks if connection fails - Fix MR list corruption, and clean up MR usage - Fix another RPCSEC_GSS issue with MIC buffer space" * tag 'nfs-for-5.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits) SUNRPC: Capture completion of all RPC tasks SUNRPC: Fix another issue with MIC buffer space NFS4: Trace lock reclaims NFS4: Trace state recovery operation NFSv4.2 fix memory leak in nfs42_ssc_open NFSv4.2 fix kfree in __nfs42_copy_file_range NFS: remove duplicated include from nfs4file.c NFSv4: Make _nfs42_proc_copy_notify() static NFS: Fallocate should use the nfs4_fattr_bitmap NFS: Return -ETXTBSY when attempting to write to a swapfile fs: nfs: sysfs: Remove NULL check before kfree NFS: remove unneeded semicolon NFSv4: add declaration of current_stateid NFSv4.x: Drop the slot if nfs4_delegreturn_prepare waits for layoutreturn NFSv4.x: Handle bad/dead sessions correctly in nfs41_sequence_process() nfsv4: Move NFSPROC4_CLNT_COPY_NOTIFY to end of list SUNRPC: Avoid RPC delays when exiting suspend NFS: Add a tracepoint in nfs_fh_to_dentry() NFSv4: Don't retry the GETATTR on old stateid in nfs4_delegreturn_done() NFSv4: Handle NFS4ERR_OLD_STATEID in delegreturn ...
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- 07 Dec, 2019 15 commits
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Steve French authored
We had cases in the previous patch where we were sending the security descriptor context on SMB3 open (file create) in cases when we hadn't mounted with with "modefromsid" mount option. Add check for that mount flag before calling ad_sd_context in open init. Signed-off-by:
Steve French <stfrench@microsoft.com> Reviewed-by:
Pavel Shilovsky <pshilov@microsoft.com>
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git://github.com/awilliam/linux-vfioLinus Torvalds authored
Pull VFIO updates from Alex Williamson: - Remove hugepage checks for reserved pfns (Ben Luo) - Fix irq-bypass unregister ordering (Jiang Yi) * tag 'vfio-v5.5-rc1' of git://github.com/awilliam/linux-vfio: vfio/pci: call irq_bypass_unregister_producer() before freeing irq vfio/type1: remove hugepage checks in is_invalid_reserved_pfn()
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git://git.kernel.org/pub/scm/linux/kernel/git/xen/tipLinus Torvalds authored
Pull more xen updates from Juergen Gross: - a patch to fix a build warning - a cleanup of no longer needed code in the Xen event handling - a small series for the Xen grant driver avoiding high order allocations and replacing an insane global limit by a per-call one - a small series fixing Xen frontend/backend module referencing * tag 'for-linus-5.5b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen-blkback: allow module to be cleanly unloaded xen/xenbus: reference count registered modules xen/gntdev: switch from kcalloc() to kvcalloc() xen/gntdev: replace global limit of mapped pages by limit per call xen/gntdev: remove redundant non-zero check on ret xen/events: remove event handling recursion detection
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Linus Torvalds authored
Merge misc Kconfig updates from Andrew Morton: "A number of changes to Kconfig files under lib/ from Changbin Du and Krzysztof Kozlowski" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: lib/: fix Kconfig indentation kernel-hacking: move DEBUG_FS to 'Generic Kernel Debugging Instruments' kernel-hacking: move DEBUG_BUGVERBOSE to 'printk and dmesg options' kernel-hacking: create a submenu for scheduler debugging options kernel-hacking: move SCHED_STACK_END_CHECK after DEBUG_STACK_USAGE kernel-hacking: move Oops into 'Lockups and Hangs' kernel-hacking: move kernel testing and coverage options to same submenu kernel-hacking: group kernel data structures debugging together kernel-hacking: create submenu for arch special debugging options kernel-hacking: group sysrq/kgdb/ubsan into 'Generic Kernel Debugging Instruments'
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Heiner Kallweit authored
In referenced fix we removed the RTL8168e-specific jumbo config for RTL8168evl in rtl_hw_jumbo_enable(). We have to do the same in rtl_hw_jumbo_disable(). v2: fix referenced commit id Fixes: 14012c9f ("r8169: fix jumbo configuration for RTL8168evl") Signed-off-by:
Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
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Linus Torvalds authored
pipe_wait() may be simple, but since it relies on the pipe lock, it means that we have to do the wakeup while holding the lock. That's unfortunate, because the very first thing the waked entity will want to do is to get the pipe lock for itself. So get rid of the pipe_wait() usage by simply releasing the pipe lock, doing the wakeup (if required) and then using wait_event_interruptible() to wait on the right condition instead. wait_event_interruptible() handles races on its own by comparing the wakeup condition before and after adding itself to the wait queue, so you can use an optimistic unlocked condition for it. Cc: David Howells <dhowells@redhat.com> Signed-off-by: -
Jiasen Lin authored
Signed-off-by:
Jiasen Lin <linjiasen@hygon.cn> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Linus Torvalds authored
This code is ancient, and goes back to when we only had a single page for the pipe buffers. The exact history is hidden in the mists of time (ie "before git", and in fact predates the BK repository too). At that long-ago point in time, it actually helped to try to merge big back-and-forth pipe reads and writes, and not limit pipe reads to the single pipe buffer in length just because that was all we had at a time. However, since then we've expanded the pipe buffers to multiple pages, and this logic really doesn't seem to make sense. And a lot of it is somewhat questionable (ie "hmm, the user asked for a non-blocking read, but we see that there's a writer pending, so let's wait anyway to get the extra data that the writer will have"). But more importantly, it makes the "go to sleep" logic much less obvious, and considering the wakeup issues we've had, I want to make for less of those kinds of things. Cc: David Howells <dhowells@redhat.com> Signed-off-by: -
Linus Torvalds authored
This is the read side version of the previous commit: it simplifies the logic to only wake up waiting writers when necessary, and makes sure to use a synchronous wakeup. This time not so much for GNU make jobserver reasons (that pipe never fills up), but simply to get the writer going quickly again. A bit less verbose commentary this time, if only because I assume that the write side commentary isn't going to be ignored if you touch this code. Cc: David Howells <dhowells@redhat.com> Signed-off-by: -
Linus Torvalds authored
The pipe rework ends up having been extra painful, partly becaused of actual bugs with ordering and caching of the pipe state, but also because of subtle performance issues. In particular, the pipe rework caused the kernel build to inexplicably slow down. The reason turns out to be that the GNU make jobserver (which limits the parallelism of the build) uses a pipe to implement a "token" system: a parallel submake will read a character from the pipe to get the job token before starting a new job, and will write a character back to the pipe when it is done. The overall job limit is thus easily controlled by just writing the appropriate number of initial token characters into the pipe. But to work well, that really means that the old behavior of write wakeups being synchronous (WF_SYNC) is very important - when the pipe writer wakes up a reader, we want the reader to actually get scheduled immediately. Otherwise you lose the parallelism of the build. The pipe rework lost that synchronous wakeup on write, and we had clearly all forgotten the reasons and rules for it. This rewrites the pipe write wakeup logic to do the required Wsync wakeups, but also clarifies the logic and avoids extraneous wakeups. It also ends up addign a number of comments about what oit does and why, so that we hopefully don't end up forgetting about this next time we change this code. Cc: David Howells <dhowells@redhat.com> Signed-off-by: -
Eric Dumazet authored
Use the new tcf_proto_check_kind() helper to make sure user provided value is well formed. BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:606 [inline] BUG: KMSAN: uninit-value in string+0x4be/0x600 lib/vsprintf.c:668 CPU: 0 PID: 12358 Comm: syz-executor.1 Not tainted 5.4.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108 __msan_warning+0x64/0xc0 mm/kmsan/kmsan_instr.c:245 string_nocheck lib/vsprintf.c:606 [inline] string+0x4be/0x600 lib/vsprintf.c:668 vsnprintf+0x218f/0x3210 lib/vsprintf.c:2510 __request_module+0x2b1/0x11c0 kernel/kmod.c:143 tcf_proto_lookup_ops+0x171/0x700 net/sched/cls_api.c:139 tc_chain_tmplt_add net/sched/cls_api.c:2730 [inline] tc_ctl_chain+0x1904/0x38a0 net/sched/cls_api.c:2850 rtnetlink_rcv_msg+0x115a/0x1580 net/core/rtnetlink.c:5224 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5242 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x110f/0x1330 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0x14ff/0x1590 net/socket.c:2311 __sys_sendmsg net/socket.c:2356 [inline] __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2363 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2363 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45a649 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0790795c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a649 RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000006 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f07907966d4 R13: 00000000004c8db5 R14: 00000000004df630 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:149 [inline] kmsan_internal_poison_shadow+0x5c/0x110 mm/kmsan/kmsan.c:132 kmsan_slab_alloc+0x97/0x100 mm/kmsan/kmsan_hooks.c:86 slab_alloc_node mm/slub.c:2773 [inline] __kmalloc_node_track_caller+0xe27/0x11a0 mm/slub.c:4381 __kmalloc_reserve net/core/skbuff.c:141 [inline] __alloc_skb+0x306/0xa10 net/core/skbuff.c:209 alloc_skb include/linux/skbuff.h:1049 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1174 [inline] netlink_sendmsg+0x783/0x1330 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0x14ff/0x1590 net/socket.c:2311 __sys_sendmsg net/socket.c:2356 [inline] __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2363 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2363 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 6f96c3c6 ("net_sched: fix backward compatibility for TCA_KIND") Signed-off-by:
Eric Dumazet <edumazet@google.com> Reported-by:
syzbot <syzkaller@googlegroups.com> Acked-by:
Cong Wang <xiyou.wangcong@gmail.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: Jiri Pirko <jiri@resnulli.us> Signed-off-by:
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Heiner Kallweit authored
RTL8125 also requires to enable RX for WoL. v2: add missing Fixes tag Fixes: f1bce4ad ("r8169: add support for RTL8125") Signed-off-by:
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Stefano Garzarella authored
When we receive a new packet from the guest, we check if the src_cid is correct, but we forgot to check the dst_cid. The host should accept only packets where dst_cid is equal to the host CID. Signed-off-by:
Stefano Garzarella <sgarzare@redhat.com> Signed-off-by:
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Grygorii Strashko authored
The commit ef87f7da ("net: phy: dp83867: move dt parsing to probe") causes regression on TI dra71x-evm and dra72x-evm, where DP83867 PHY is used in "rgmii-id" mode - the networking stops working. Unfortunately, it's not enough to just move DT parsing code to .probe() as it depends on phydev->interface value, which is set to correct value abter the .probe() is completed and before calling .config_init(). So, RGMII configuration can't be loaded from DT. To fix and issue - move RGMII validation code to .config_init() - parse RGMII parameters in dp83867_of_init(), but consider them as optional. Fixes: ef87f7da ("net: phy: dp83867: move dt parsing to probe") Signed-off-by:
Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by:
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Grygorii Strashko authored
Now RX interrupt is triggered twice every time, because in cpsw_rx_interrupt() it is asked first and then disabled. So there will be pending interrupt always, when RX interrupt is enabled again in NAPI handler. Fix it by first disabling IRQ and then do ask. Fixes: 870915fe ("drivers: net: cpsw: remove disable_irq/enable_irq as irq can be masked from cpsw itself") Signed-off-by:
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