- 17 Oct, 2019 22 commits
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Johan Hovold authored
commit 93ddb1f5 upstream. The driver was accessing its struct usb_interface in its release() callback without holding a reference. This would lead to a use-after-free whenever the device was disconnected while the character device was still open. Fixes: 66e3e591 ("usb: Add driver for Altus Metrum ChaosKey device (v2)") Cc: stable <stable@vger.kernel.org> # 4.1 Signed-off-by:
Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191009153848.8664-3-johan@kernel.orgSigned-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Johan Hovold authored
commit 9a315358 upstream. Since commit c2b71462 ("USB: core: Fix bug caused by duplicate interface PM usage counter") USB drivers must always balance their runtime PM gets and puts, including when the driver has already been unbound from the interface. Leaving the interface with a positive PM usage counter would prevent a later bound driver from suspending the device. Fixes: c2b71462 ("USB: core: Fix bug caused by duplicate interface PM usage counter") Cc: stable <stable@vger.kernel.org> Signed-off-by:
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Johan Hovold authored
commit b5f8d468 upstream. Make sure to stop also the asynchronous write URBs on disconnect() to avoid use-after-free in the completion handler after driver unbind. Fixes: 946b960d ("USB: add driver for iowarrior devices.") Cc: stable <stable@vger.kernel.org> # 2.6.21: 51a2f077 ("USB: introduce usb_anchor") Signed-off-by:
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Johan Hovold authored
commit 80cd5479 upstream. The driver was accessing its struct usb_interface from its release() callback without holding a reference. This would lead to a use-after-free whenever debugging was enabled and the device was disconnected while its character device was open. Fixes: 549e8350 ("USB: iowarrior: Convert local dbg macro to dev_dbg") Cc: stable <stable@vger.kernel.org> # 3.16 Signed-off-by:
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Johan Hovold authored
commit edc4746f upstream. A recent fix addressing a deadlock on disconnect introduced a new bug by moving the present flag out of the critical section protected by the driver-data mutex. This could lead to a racing release() freeing the driver data before disconnect() is done with it. Due to insufficient locking a related use-after-free could be triggered also before the above mentioned commit. Specifically, the driver needs to hold the driver-data mutex also while checking the opened flag at disconnect(). Fixes: c468a8aa ("usb: iowarrior: fix deadlock on disconnect") Fixes: 946b960d ("USB: add driver for iowarrior devices.") Cc: stable <stable@vger.kernel.org> # 2.6.21 Reported-by: syzbot+0761012cebf7bdb38137@syzkaller.appspotmail.com Signed-off-by:
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Johan Hovold authored
commit 123a0f12 upstream. The driver was accessing its struct usb_device in its release() callback without holding a reference. This would lead to a use-after-free whenever the device was disconnected while the character device was still open. Fixes: 66d4bc30 ("USB: adutux: remove custom debug macro") Cc: stable <stable@vger.kernel.org> # 3.12 Signed-off-by:
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Johan Hovold authored
commit b2fa7bae upstream. The driver was using its struct usb_device pointer as an inverted disconnected flag, but was setting it to NULL before making sure all completion handlers had run. This could lead to a NULL-pointer dereference in a number of dev_dbg statements in the completion handlers which relies on said pointer. The pointer was also dereferenced unconditionally in a dev_dbg statement release() something which would lead to a NULL-deref whenever a device was disconnected before the final character-device close if debugging was enabled. Fix this by unconditionally stopping all I/O and preventing resubmissions by poisoning the interrupt URBs at disconnect and using a dedicated disconnected flag. This also makes sure that all I/O has completed by the time the disconnect callback returns. Fixes: 1ef37c60 ("USB: adutux: remove custom debug macro and module parameter") Fixes: 66d4bc30 ("USB: adutux: remove custom debug macro") Cc: stable <stable@vger.kernel.org> # 3.12 Signed-off-by:
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Johan Hovold authored
commit 44efc269 upstream. The driver was clearing its struct usb_device pointer, which it used as an inverted disconnected flag, before deregistering the character device and without serialising against racing release(). This could lead to a use-after-free if a racing release() callback observes the cleared pointer and frees the driver data before disconnect() is finished with it. This could also lead to NULL-pointer dereferences in a racing open(). Fixes: f08812d5 ("USB: FIx locks and urb->status in adutux (updated)") Cc: stable <stable@vger.kernel.org> # 2.6.24 Reported-by: syzbot+0243cb250a51eeefb8cc@syzkaller.appspotmail.com Tested-by: syzbot+0243cb250a51eeefb8cc@syzkaller.appspotmail.com Signed-off-by:
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Kai-Heng Feng authored
commit ac343366 upstream. After commit f7fac17c ("xhci: Convert xhci_handshake() to use readl_poll_timeout_atomic()"), ASMedia xHCI may fail to suspend. Although the algorithms are essentially the same, the old max timeout is (usec + usec * time of doing readl()), and the new max timeout is just usec, which is much less than the old one. Increase the timeout to make ASMedia xHCI able to suspend again. BugLink: https://bugs.launchpad.net/bugs/1844021 Fixes: f7fac17c ("xhci: Convert xhci_handshake() to use readl_poll_timeout_atomic()") Cc: <stable@vger.kernel.org> # v5.2+ Signed-off-by:
Kai-Heng Feng <kai.heng.feng@canonical.com> Signed-off-by:
Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/1570190373-30684-8-git-send-email-mathias.nyman@linux.intel.comSigned-off-by:
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Bill Kuzeja authored
commit 8de66b0e upstream. The system can hit a deadlock if an xhci adapter breaks while initializing. The deadlock is between two threads: thread 1 is tearing down the adapter and is stuck in usb_unlocked_disable_lpm waiting to lock the hcd->handwidth_mutex. Thread 2 is holding this mutex (while still trying to add a usb device), but is stuck in xhci_endpoint_reset waiting for a stop or config command to complete. A reboot is required to resolve. It turns out when calling xhci_queue_stop_endpoint and xhci_queue_configure_endpoint in xhci_endpoint_reset, the return code is not checked for errors. If the timing is right and the adapter dies just before either of these commands get issued, we hang indefinitely waiting for a completion on a command that didn't get issued. This wasn't a problem before the following fix because we didn't send commands in xhci_endpoint_reset: commit f5249461 ("xhci: Clear the host side toggle manually when endpoint is soft reset") With the patch I am submitting, a duration test which breaks adapters during initialization (and which deadlocks with the standard kernel) runs without issue. Fixes: f5249461 ("xhci: Clear the host side toggle manually when endpoint is soft reset") Cc: <stable@vger.kernel.org> # v4.17+ Cc: Torez Smith <torez@redhat.com> Signed-off-by:
Bill Kuzeja <william.kuzeja@stratus.com> Signed-off-by:
Torez Smith <torez@redhat.com> Signed-off-by:
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Rick Tseng authored
commit a70bcbc3 upstream. NVIDIA 3.1 xHCI card would lose power when moving power state into D3Cold. Thus we need to wait for CNR bit to clear in xhci resume, just as in xhci init. [Minor changes to comment and commit message -Mathias] Cc: <stable@vger.kernel.org> Signed-off-by:
Rick Tseng <rtseng@nvidia.com> Signed-off-by:
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Mathias Nyman authored
commit 47f50d61 upstream. Early xHCI 1.1 spec did not mention USB 3.1 capable hosts should set sbrn to 0x31, or that the minor revision is a two digit BCD containing minor and sub-minor numbers. This was later clarified in xHCI 1.2. Some USB 3.1 capable hosts therefore have sbrn set to 0x30, or minor revision set to 0x1 instead of 0x10. Detect the USB 3.1 capability correctly for these hosts as well Fixes: ddd57980 ("xhci: detect USB 3.2 capable host controllers correctly") Cc: <stable@vger.kernel.org> # v4.18+ Cc: Loïc Yhuel <loic.yhuel@gmail.com> Signed-off-by:
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Jan Schmidt authored
commit d500c63f upstream. If an endpoint is encountered that returns USB3_LPM_DEVICE_INITIATED, keep checking further endpoints, as there might be periodic endpoints later that return USB3_LPM_DISABLED due to shorter service intervals. Without this, the code can set too high a maximum-exit-latency and prevent the use of multiple USB3 cameras that should be able to work. Cc: <stable@vger.kernel.org> Signed-off-by:
Jan Schmidt <jan@centricular.com> Tested-by:
Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by:
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Mathias Nyman authored
commit cd9d9491 upstream. If host/hub initiated link pm is prevented by a driver flag we still must ensure that periodic endpoints have longer service intervals than link pm exit latency before allowing device initiated link pm. Fix this by continue walking and checking endpoint service interval if xhci_get_timeout_no_hub_lpm() returns anything else than USB3_LPM_DISABLED While at it fix the split line error message Tested-by:
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Mathias Nyman authored
commit c03101ff upstream. The check printing out the "WARN Wrong bounce buffer write length:" uses incorrect values when comparing bytes written from scatterlist to bounce buffer. Actual copied lengths are fine. The used seg->bounce_len will be set to equal new_buf_len a few lines later in the code, but is incorrect when doing the comparison. The patch which added this false warning was backported to 4.8+ kernels so this should be backported as far as well. Cc: <stable@vger.kernel.org> # v4.8+ Fixes: 597c56e3 ("xhci: update bounce buffer with correct sg num") Signed-off-by:
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Johan Hovold authored
commit bed5ef23 upstream. The driver was using its struct usb_interface pointer as an inverted disconnected flag and was setting it to NULL before making sure all completion handlers had run. This could lead to NULL-pointer dereferences in the dev_err() statements in the completion handlers which relies on said pointer. Fix this by using a dedicated disconnected flag. Note that this is also addresses a NULL-pointer dereference at release() and a struct usb_interface reference leak introduced by a recent runtime PM fix, which depends on and should have been submitted together with this patch. Fixes: 4212cd74 ("USB: usb-skeleton.c: remove err() usage") Fixes: 5c290a5e ("USB: usb-skeleton: fix runtime PM after driver unbind") Cc: stable <stable@vger.kernel.org> Signed-off-by:
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Johan Hovold authored
commit 5c290a5e upstream. Since commit c2b71462 ("USB: core: Fix bug caused by duplicate interface PM usage counter") USB drivers must always balance their runtime PM gets and puts, including when the driver has already been unbound from the interface. Leaving the interface with a positive PM usage counter would prevent a later bound driver from suspending the device. Fixes: c2b71462 ("USB: core: Fix bug caused by duplicate interface PM usage counter") Cc: stable <stable@vger.kernel.org> Signed-off-by:
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Johan Hovold authored
commit aafb00a9 upstream. The driver was using its struct usb_interface pointer as an inverted disconnected flag, but was setting it to NULL without making sure all code paths that used it were done with it. Before commit ef61eb43 ("USB: yurex: Fix protection fault after device removal") this included the interrupt-in completion handler, but there are further accesses in dev_err and dev_dbg statements in yurex_write() and the driver-data destructor (sic!). Fix this by unconditionally stopping also the control URB at disconnect and by using a dedicated disconnected flag. Note that we need to take a reference to the struct usb_interface to avoid a use-after-free in the destructor whenever the device was disconnected while the character device was still open. Fixes: aadd6472 ("USB: yurex.c: remove dbg() usage") Fixes: 45714104 ("USB: yurex.c: remove err() usage") Cc: stable <stable@vger.kernel.org> # 3.5: ef61eb43Signed-off-by:
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Alan Stern authored
commit 32a0721c upstream. According to Greg KH, it has been generally agreed that when a USB driver encounters an unknown error (or one it can't handle directly), it should just give up instead of going into a potentially infinite retry loop. The three codes -EPROTO, -EILSEQ, and -ETIME fall into this category. They can be caused by bus errors such as packet loss or corruption, attempting to communicate with a disconnected device, or by malicious firmware. Nowadays the extent of packet loss or corruption is negligible, so it should be safe for a driver to give up whenever one of these errors occurs. Although the yurex driver handles -EILSEQ errors in this way, it doesn't do the same for -EPROTO (as discovered by the syzbot fuzzer) or other unrecognized errors. This patch adjusts the driver so that it doesn't log an error message for -EPROTO or -ETIME, and it doesn't retry after any errors. Reported-and-tested-by: syzbot+b24d736f18a1541ad550@syzkaller.appspotmail.com Signed-off-by:
Alan Stern <stern@rowland.harvard.edu> CC: Tomoki Sekiyama <tomoki.sekiyama@gmail.com> CC: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.1909171245410.1590-100000@iolanthe.rowland.orgSigned-off-by:
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Bastien Nocera authored
commit 015664d1 upstream. The Rio500 kernel driver has not been used by Rio500 owners since 2001 not long after the rio500 project added support for a user-space USB stack through the very first versions of usbdevfs and then libusb. Support for the kernel driver was removed from the upstream utilities in 2008: https://gitlab.freedesktop.org/hadess/rio500/commit/943f624ab721eb8281c287650fcc9e2026f6f5db Cc: Cesar Miquel <miquel@df.uba.ar> Signed-off-by:
Bastien Nocera <hadess@hadess.net> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/6251c17584d220472ce882a3d9c199c401a51a71.camel@hadess.netSigned-off-by:
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Icenowy Zheng authored
[ Upstream commit 38fb6d0e ] The kernel mount_block_root() function expects -EACESS or -EINVAL for a unmountable filesystem when trying to mount the root with different filesystem types. However, in 5.3-rc1 the behavior when F2FS code cannot find valid block changed to return -EFSCORRUPTED(-EUCLEAN), and this error code makes mount_block_root() fail when trying to probe F2FS. When the magic number of the superblock mismatches, it has a high probability that it's just not a F2FS. In this case return -EINVAL seems to be a better result, and this return value can make mount_block_root() probing work again. Return -EINVAL when the superblock has magic mismatch, -EFSCORRUPTED in other cases (the magic matches but the superblock cannot be recognized). Fixes: 10f966bb ("f2fs: use generic EFSBADCRC/EFSCORRUPTED") Signed-off-by:
Icenowy Zheng <icenowy@aosc.io> Reviewed-by:
Chao Yu <yuchao0@huawei.com> Signed-off-by:
Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by:
Sasha Levin <sashal@kernel.org>
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Will Deacon authored
commit 20bb759a upstream. Calling 'panic()' on a kernel with CONFIG_PREEMPT=y can leave the calling CPU in an infinite loop, but with interrupts and preemption enabled. From this state, userspace can continue to be scheduled, despite the system being "dead" as far as the kernel is concerned. This is easily reproducible on arm64 when booting with "nosmp" on the command line; a couple of shell scripts print out a periodic "Ping" message whilst another triggers a crash by writing to /proc/sysrq-trigger: | sysrq: Trigger a crash | Kernel panic - not syncing: sysrq triggered crash | CPU: 0 PID: 1 Comm: init Not tainted 5.2.15 #1 | Hardware name: linux,dummy-virt (DT) | Call trace: | dump_backtrace+0x0/0x148 | show_stack+0x14/0x20 | dump_stack+0xa0/0xc4 | panic+0x140/0x32c | sysrq_handle_reboot+0x0/0x20 | __handle_sysrq+0x124/0x190 | write_sysrq_trigger+0x64/0x88 | proc_reg_write+0x60/0xa8 | __vfs_write+0x18/0x40 | vfs_write+0xa4/0x1b8 | ksys_write+0x64/0xf0 | __arm64_sys_write+0x14/0x20 | el0_svc_common.constprop.0+0xb0/0x168 | el0_svc_handler+0x28/0x78 | el0_svc+0x8/0xc | Kernel Offset: disabled | CPU features: 0x0002,24002004 | Memory Limit: none | ---[ end Kernel panic - not syncing: sysrq triggered crash ]--- | Ping 2! | Ping 1! | Ping 1! | Ping 2! The issue can also be triggered on x86 kernels if CONFIG_SMP=n, otherwise local interrupts are disabled in 'smp_send_stop()'. Disable preemption in 'panic()' before re-enabling interrupts. Link: http://lkml.kernel.org/r/20191002123538.22609-1-will@kernel.org Link: https://lore.kernel.org/r/BX1W47JXPMR8.58IYW53H6M5N@dragonstoneSigned-off-by:
Will Deacon <will@kernel.org> Reported-by:
Xogium <contact@xogium.me> Reviewed-by:
Kees Cook <keescook@chromium.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Feng Tang <feng.tang@intel.com> Cc: <stable@vger.kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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- 11 Oct, 2019 18 commits
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Greg Kroah-Hartman authored
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Johannes Berg authored
commit f88eb7c0 upstream. We currently don't validate the beacon head, i.e. the header, fixed part and elements that are to go in front of the TIM element. This means that the variable elements there can be malformed, e.g. have a length exceeding the buffer size, but most downstream code from this assumes that this has already been checked. Add the necessary checks to the netlink policy. Cc: stable@vger.kernel.org Fixes: ed1b6cc7 ("cfg80211/nl80211: add beacon settings") Link: https://lore.kernel.org/r/1569009255-I7ac7fbe9436e9d8733439eab8acbbd35e55c74ef@changeidSigned-off-by:
Johannes Berg <johannes.berg@intel.com> Signed-off-by:
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Jouni Malinen authored
commit 7388afe0 upstream. Enforce the first argument to be a correct type of a pointer to struct element and avoid unnecessary typecasts from const to non-const pointers (the change in validate_ie_attr() is needed to make this part work). In addition, avoid signed/unsigned comparison within for_each_element() and mark struct element packed just in case. Signed-off-by:
Jouni Malinen <j@w1.fi> Signed-off-by:
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Johannes Berg authored
commit 0f3b07f0 upstream. Rather than always iterating elements from frames with pure u8 pointers, add a type "struct element" that encapsulates the id/datalen/data format of them. Then, add the element iteration macros * for_each_element * for_each_element_id * for_each_element_extid which take, as their first 'argument', such a structure and iterate through a given u8 array interpreting it as elements. While at it and since we'll need it, also add * for_each_subelement * for_each_subelement_id * for_each_subelement_extid which instead of taking data/length just take an outer element and use its data/datalen. Also add for_each_element_completed() to determine if any of the loops above completed, i.e. it was able to parse all of the elements successfully and no data remained. Use for_each_element_id() in cfg80211_find_ie_match() as the first user of this. Signed-off-by:
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Gao Xiang authored
commit e12a0ce2 upstream. As reported by erofs-utils fuzzer, currently, multiref (ondisk deduplication) hasn't been supported for now, we should forbid it properly. Fixes: 3883a79a ("staging: erofs: introduce VLE decompression support") Cc: <stable@vger.kernel.org> # 4.19+ Signed-off-by:
Gao Xiang <gaoxiang25@huawei.com> Reviewed-by:
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Gao Xiang authored
commit 138e1a09 upstream. As reported by erofs-utils fuzzer, these error handling path will be entered to handle corrupted images. Lack of erofs_workgroup_puts will cause unmounting unsuccessfully. Fix these return values to EFSCORRUPTED as well. Fixes: 3883a79a ("staging: erofs: introduce VLE decompression support") Cc: <stable@vger.kernel.org> # 4.19+ Signed-off-by:
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Gao Xiang authored
commit ee45197c upstream. As reported by erofs_utils fuzzer, a logical page can belong to at most 2 compressed clusters, if one compressed cluster is corrupted, but the other has been ready in submitting chain. The chain needs to submit anyway in order to keep the page working properly (page unlocked with PG_error set, PG_uptodate not set). Let's fix it now. Fixes: 3883a79a ("staging: erofs: introduce VLE decompression support") Cc: <stable@vger.kernel.org> # 4.19+ Signed-off-by:
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Gao Xiang authored
commit acb383f1 upstream. Richard observed a forever loop of erofs_read_raw_page() [1] which can be generated by forcely setting ->u.i_blkaddr to 0xdeadbeef (as my understanding block layer can handle access beyond end of device correctly). After digging into that, it seems the problem is highly related with directories and then I found the root cause is an improper error handling in erofs_readdir(). Let's fix it now. [1] https://lore.kernel.org/r/1163995781.68824.1566084358245.JavaMail.zimbra@nod.at/Reported-by:
Richard Weinberger <richard@nod.at> Fixes: 3aa8ec71 ("staging: erofs: add directory operations") Cc: <stable@vger.kernel.org> # 4.19+ Reviewed-by:
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Andrew Murray authored
commit 1004ce4c upstream. Synchronization is recommended before disabling the trace registers to prevent any start or stop points being speculative at the point of disabling the unit (section 7.3.77 of ARM IHI 0064D). Synchronization is also recommended after programming the trace registers to ensure all updates are committed prior to normal code resuming (section 4.3.7 of ARM IHI 0064D). Let's ensure these syncronization points are present in the code and clearly commented. Note that we could rely on the barriers in CS_LOCK and coresight_disclaim_device_unlocked or the context switch to user space - however coresight may be of use in the kernel. On armv8 the mb macro is defined as dsb(sy) - Given that the etm4x is only used on armv8 let's directly use dsb(sy) instead of mb(). This removes some ambiguity and makes it easier to correlate the code with the TRM. Signed-off-by:
Andrew Murray <andrew.murray@arm.com> Reviewed-by:
Suzuki K Poulose <suzuki.poulose@arm.com> [Fixed capital letter for "use" in title] Signed-off-by:
Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20190829202842.580-11-mathieu.poirier@linaro.org Cc: stable@vger.kernel.org # 4.9+ Signed-off-by:
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Eric Sandeen authored
commit cc3a7bfe upstream. Today, put_compat_statfs64() disallows nearly any field value over 2^32 if f_bsize is only 32 bits, but that makes no sense. compat_statfs64 is there for the explicit purpose of providing 64-bit fields for f_files, f_ffree, etc. And f_bsize is always only 32 bits. As a result, 32-bit userspace gets -EOVERFLOW for i.e. large file counts even with -D_FILE_OFFSET_BITS=64 set. In reality, only f_bsize and f_frsize can legitimately overflow (fields like f_type and f_namelen should never be large), so test only those fields. This bug was discussed at length some time ago, and this is the proposal Al suggested at https://lkml.org/lkml/2018/8/6/640. It seemed to get dropped amid the discussion of other related changes, but this part seems obviously correct on its own, so I've picked it up and sent it, for expediency. Fixes: 64d2ab32 ("vfs: fix put_compat_statfs64() does not handle errors") Signed-off-by:
Eric Sandeen <sandeen@redhat.com> Signed-off-by:
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Josh Poimboeuf authored
commit a111b7c0 upstream. Configure arm64 runtime CPU speculation bug mitigations in accordance with the 'mitigations=' cmdline option. This affects Meltdown, Spectre v2, and Speculative Store Bypass. The default behavior is unchanged. Signed-off-by:
Josh Poimboeuf <jpoimboe@redhat.com> [will: reorder checks so KASLR implies KPTI and SSBS is affected by cmdline] Signed-off-by:
Will Deacon <will.deacon@arm.com> Signed-off-by:
Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by:
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Marc Zyngier authored
commit 517953c2 upstream. The SMCCC ARCH_WORKAROUND_1 service can indicate that although the firmware knows about the Spectre-v2 mitigation, this particular CPU is not vulnerable, and it is thus not necessary to call the firmware on this CPU. Let's use this information to our benefit. Signed-off-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
Jeremy Linton <jeremy.linton@arm.com> Reviewed-by:
Andre Przywara <andre.przywara@arm.com> Reviewed-by:
Catalin Marinas <catalin.marinas@arm.com> Tested-by:
Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by:
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Marc Zyngier authored
[ Upstream commit cbdf8a18 ] On a CPU that doesn't support SSBS, PSTATE[12] is RES0. In a system where only some of the CPUs implement SSBS, we end-up losing track of the SSBS bit across task migration. To address this issue, let's force the SSBS bit on context switch. Fixes: 8f04e8e6 ("arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3") Signed-off-by:
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Will Deacon authored
[ Upstream commit eb337cdf ] SSBS provides a relatively cheap mitigation for SSB, but it is still a mitigation and its presence does not indicate that the CPU is unaffected by the vulnerability. Tweak the mitigation logic so that we report the correct string in sysfs. Signed-off-by:
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Jeremy Linton authored
[ Upstream commit 526e065d ] Return status based on ssbd_state and __ssb_safe. If the mitigation is disabled, or the firmware isn't responding then return the expected machine state based on a whitelist of known good cores. Given a heterogeneous machine, the overall machine vulnerability defaults to safe but is reset to unsafe when we miss the whitelist and the firmware doesn't explicitly tell us the core is safe. In order to make that work we delay transitioning to vulnerable until we know the firmware isn't responding to avoid a case where we miss the whitelist, but the firmware goes ahead and reports the core is not vulnerable. If all the cores in the machine have SSBS, then __ssb_safe will remain true. Tested-by:
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Jeremy Linton authored
[ Upstream commit d2532e27 ] Track whether all the cores in the machine are vulnerable to Spectre-v2, and whether all the vulnerable cores have been mitigated. We then expose this information to userspace via sysfs. Signed-off-by:
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Jeremy Linton authored
[ Upstream commit 8c1e3d2b ] Ensure we are always able to detect whether or not the CPU is affected by Spectre-v2, so that we can later advertise this to userspace. Signed-off-by:
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Marc Zyngier authored
[ Upstream commit 73f38166 ] We currently have a list of CPUs affected by Spectre-v2, for which we check that the firmware implements ARCH_WORKAROUND_1. It turns out that not all firmwares do implement the required mitigation, and that we fail to let the user know about it. Instead, let's slightly revamp our checks, and rely on a whitelist of cores that are known to be non-vulnerable, and let the user know the status of the mitigation in the kernel log. Signed-off-by:
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