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VC4 + udlfb #26
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I don't have any UDL devices, so I don't really have a way to test this. It may end up getting fixed as part of camera/video decode support, thought. |
anholt
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…ted yet When enabling the below kernel configs: CONFIG_DEFERRED_STRUCT_PAGE_INIT CONFIG_DEBUG_PAGEALLOC CONFIG_PAGE_EXTENSION CONFIG_DEBUG_VM kernel bootup may fail due to the following oops: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 PGD 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 11 PID: 106 Comm: pgdatinit1 Not tainted 4.6.0-rc5-next-20160427 #26 Hardware name: Intel Corporation S5520HC/S5520HC, BIOS S5500.86B.01.10.0025.030220091519 03/02/2009 task: ffff88017c080040 ti: ffff88017c084000 task.ti: ffff88017c084000 RIP: 0010:[<ffffffff8118d982>] [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 RSP: 0000:ffff88017c087c48 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000980 RSI: 0000000000000080 RDI: 0000000000660401 RBP: ffff88017c087cd0 R08: 0000000000000401 R09: 0000000000000009 R10: ffff88017c080040 R11: 000000000000000a R12: 0000000000000400 R13: ffffea0019810000 R14: ffffea0019810040 R15: ffff88066cfe6080 FS: 0000000000000000(0000) GS:ffff88066cd40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000002406000 CR4: 00000000000006e0 Call Trace: free_hot_cold_page+0x192/0x1d0 __free_pages+0x5c/0x90 __free_pages_boot_core+0x11a/0x14e deferred_free_range+0x50/0x62 deferred_init_memmap+0x220/0x3c3 kthread+0xf8/0x110 ret_from_fork+0x22/0x40 Code: 49 89 d4 48 c1 e0 06 49 01 c5 e9 de fe ff ff 4c 89 f7 44 89 4d b8 4c 89 45 c0 44 89 5d c8 48 89 4d d0 e8 62 c7 07 00 48 8b 4d d0 <48> 8b 00 44 8b 5d c8 4c 8b 45 c0 44 8b 4d b8 a8 02 0f 84 05 ff RIP [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 RSP <ffff88017c087c48> CR2: 0000000000000000 The problem is lookup_page_ext() returns NULL then page_is_guard() tried to access it in page freeing. page_is_guard() depends on PAGE_EXT_DEBUG_GUARD bit of page extension flag, but freeing page might reach here before the page_ext arrays are allocated when feeding a range of pages to the allocator for the first time during bootup or memory hotplug. When it returns NULL, page_is_guard() should just return false instead of checking PAGE_EXT_DEBUG_GUARD unconditionally. Link: http://lkml.kernel.org/r/1463610225-29060-1-git-send-email-yang.shi@linaro.org Signed-off-by: Yang Shi <yang.shi@linaro.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
anholt
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When DEFERRED_STRUCT_PAGE_INIT is enabled, just a subset of memmap at boot are initialized, then the rest are initialized in parallel by starting one-off "pgdatinitX" kernel thread for each node X. If page_ext_init is called before it, some pages will not have valid extension, this may lead the below kernel oops when booting up kernel: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 PGD 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 11 PID: 106 Comm: pgdatinit1 Not tainted 4.6.0-rc5-next-20160427 #26 Hardware name: Intel Corporation S5520HC/S5520HC, BIOS S5500.86B.01.10.0025.030220091519 03/02/2009 task: ffff88017c080040 ti: ffff88017c084000 task.ti: ffff88017c084000 RIP: 0010:[<ffffffff8118d982>] [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 RSP: 0000:ffff88017c087c48 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000980 RSI: 0000000000000080 RDI: 0000000000660401 RBP: ffff88017c087cd0 R08: 0000000000000401 R09: 0000000000000009 R10: ffff88017c080040 R11: 000000000000000a R12: 0000000000000400 R13: ffffea0019810000 R14: ffffea0019810040 R15: ffff88066cfe6080 FS: 0000000000000000(0000) GS:ffff88066cd40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000002406000 CR4: 00000000000006e0 Call Trace: free_hot_cold_page+0x192/0x1d0 __free_pages+0x5c/0x90 __free_pages_boot_core+0x11a/0x14e deferred_free_range+0x50/0x62 deferred_init_memmap+0x220/0x3c3 kthread+0xf8/0x110 ret_from_fork+0x22/0x40 Code: 49 89 d4 48 c1 e0 06 49 01 c5 e9 de fe ff ff 4c 89 f7 44 89 4d b8 4c 89 45 c0 44 89 5d c8 48 89 4d d0 e8 62 c7 07 00 48 8b 4d d0 <48> 8b 00 44 8b 5d c8 4c 8b 45 c0 44 8b 4d b8 a8 02 0f 84 05 ff RIP [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 RSP <ffff88017c087c48> CR2: 0000000000000000 Move page_ext_init() after page_alloc_init_late() to make sure page extension is setup for all pages. Link: http://lkml.kernel.org/r/1463696006-31360-1-git-send-email-yang.shi@linaro.org Signed-off-by: Yang Shi <yang.shi@linaro.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
You'll probably want to look into something like https://wiki.archlinux.org/index.php/DisplayLink for how to set up UDL these days. Ultimately, this is not a vc4 driver issue, just Xorg configuration for UDL, so closing. |
anholt
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Jan 23, 2017
commit 1c7de2b upstream. There is at least one Chelsio 10Gb card which uses VPD area to store some non-standard blocks (example below). However pci_vpd_size() returns the length of the first block only assuming that there can be only one VPD "End Tag". Since 4e1a635 ("vfio/pci: Use kernel VPD access functions"), VFIO blocks access beyond that offset, which prevents the guest "cxgb3" driver from probing the device. The host system does not have this problem as its driver accesses the config space directly without pci_read_vpd(). Add a quirk to override the VPD size to a bigger value. The maximum size is taken from EEPROMSIZE in drivers/net/ethernet/chelsio/cxgb3/common.h. We do not read the tag as the cxgb3 driver does as the driver supports writing to EEPROM/VPD and when it writes, it only checks for 8192 bytes boundary. The quirk is registered for all devices supported by the cxgb3 driver. This adds a quirk to the PCI layer (not to the cxgb3 driver) as the cxgb3 driver itself accesses VPD directly and the problem only exists with the vfio-pci driver (when cxgb3 is not running on the host and may not be even loaded) which blocks accesses beyond the first block of VPD data. However vfio-pci itself does not have quirks mechanism so we add it to PCI. This is the controller: Ethernet controller [0200]: Chelsio Communications Inc T310 10GbE Single Port Adapter [1425:0030] This is what I parsed from its VPD: === b'\x82*\x0010 Gigabit Ethernet-SR PCI Express Adapter\x90J\x00EC\x07D76809 FN\x0746K' 0000 Large item 42 bytes; name 0x2 Identifier String b'10 Gigabit Ethernet-SR PCI Express Adapter' 002d Large item 74 bytes; name 0x10 #00 [EC] len=7: b'D76809 ' #0a [FN] len=7: b'46K7897' #14 [PN] len=7: b'46K7897' #1e [MN] len=4: b'1037' #25 [FC] len=4: b'5769' #2c [SN] len=12: b'YL102035603V' #3b [NA] len=12: b'00145E992ED1' 007a Small item 1 bytes; name 0xf End Tag 0c00 Large item 16 bytes; name 0x2 Identifier String b'S310E-SR-X ' 0c13 Large item 234 bytes; name 0x10 #00 [PN] len=16: b'TBD ' #13 [EC] len=16: b'110107730D2 ' #26 [SN] len=16: b'97YL102035603V ' #39 [NA] len=12: b'00145E992ED1' #48 [V0] len=6: b'175000' #51 [V1] len=6: b'266666' #5a [V2] len=6: b'266666' #63 [V3] len=6: b'2000 ' #6c [V4] len=2: b'1 ' #71 [V5] len=6: b'c2 ' #7a [V6] len=6: b'0 ' #83 [V7] len=2: b'1 ' #88 [V8] len=2: b'0 ' #8d [V9] len=2: b'0 ' #92 [VA] len=2: b'0 ' #97 [RV] len=80: b's\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'... 0d00 Large item 252 bytes; name 0x11 #00 [VC] len=16: b'122310_1222 dp ' #13 [VD] len=16: b'610-0001-00 H1\x00\x00' #26 [VE] len=16: b'122310_1353 fp ' #39 [VF] len=16: b'610-0001-00 H1\x00\x00' #4c [RW] len=173: b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'... 0dff Small item 0 bytes; name 0xf End Tag 10f3 Large item 13315 bytes; name 0x62 !!! unknown item name 98: b'\xd0\x03\x00@`\x0c\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00' === Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
anholt
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Mar 30, 2017
[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
anholt
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Mar 30, 2017
[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
anholt
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As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
anholt
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Apr 8, 2017
lockdep doesn't like us taking the mm->mmap_sem inside the get_pages callback for a couple of reasons. The straightforward deadlock: [13755.434059] ============================================= [13755.434061] [ INFO: possible recursive locking detected ] [13755.434064] 4.11.0-rc1-CI-CI_DRM_297+ #1 Tainted: G U [13755.434066] --------------------------------------------- [13755.434068] gem_userptr_bli/8398 is trying to acquire lock: [13755.434070] (&mm->mmap_sem){++++++}, at: [<ffffffffa00c988a>] i915_gem_userptr_get_pages+0x5a/0x2e0 [i915] [13755.434096] but task is already holding lock: [13755.434098] (&mm->mmap_sem){++++++}, at: [<ffffffff8104d485>] __do_page_fault+0x105/0x560 [13755.434105] other info that might help us debug this: [13755.434108] Possible unsafe locking scenario: [13755.434110] CPU0 [13755.434111] ---- [13755.434112] lock(&mm->mmap_sem); [13755.434115] lock(&mm->mmap_sem); [13755.434117] *** DEADLOCK *** [13755.434121] May be due to missing lock nesting notation [13755.434126] 2 locks held by gem_userptr_bli/8398: [13755.434128] #0: (&mm->mmap_sem){++++++}, at: [<ffffffff8104d485>] __do_page_fault+0x105/0x560 [13755.434135] #1: (&obj->mm.lock){+.+.+.}, at: [<ffffffffa00b887d>] __i915_gem_object_get_pages+0x1d/0x70 [i915] [13755.434156] stack backtrace: [13755.434161] CPU: 3 PID: 8398 Comm: gem_userptr_bli Tainted: G U 4.11.0-rc1-CI-CI_DRM_297+ #1 [13755.434165] Hardware name: GIGABYTE GB-BKi7(H)A-7500/MFLP7AP-00, BIOS F4 02/20/2017 [13755.434169] Call Trace: [13755.434174] dump_stack+0x67/0x92 [13755.434178] __lock_acquire+0x133a/0x1b50 [13755.434182] lock_acquire+0xc9/0x220 [13755.434200] ? i915_gem_userptr_get_pages+0x5a/0x2e0 [i915] [13755.434204] down_read+0x42/0x70 [13755.434221] ? i915_gem_userptr_get_pages+0x5a/0x2e0 [i915] [13755.434238] i915_gem_userptr_get_pages+0x5a/0x2e0 [i915] [13755.434255] ____i915_gem_object_get_pages+0x25/0x60 [i915] [13755.434272] __i915_gem_object_get_pages+0x59/0x70 [i915] [13755.434288] i915_gem_fault+0x397/0x6a0 [i915] [13755.434304] ? i915_gem_fault+0x1a1/0x6a0 [i915] [13755.434308] ? __lock_acquire+0x449/0x1b50 [13755.434311] ? __lock_acquire+0x449/0x1b50 [13755.434315] ? vm_mmap_pgoff+0xa9/0xd0 [13755.434318] __do_fault+0x19/0x70 [13755.434321] __handle_mm_fault+0x863/0xe50 [13755.434325] handle_mm_fault+0x17f/0x370 [13755.434329] ? handle_mm_fault+0x40/0x370 [13755.434332] __do_page_fault+0x279/0x560 [13755.434336] do_page_fault+0xc/0x10 [13755.434339] page_fault+0x22/0x30 [13755.434342] RIP: 0033:0x7f5ab91b5880 [13755.434345] RSP: 002b:00007fff62922218 EFLAGS: 00010216 [13755.434348] RAX: 0000000000b74500 RBX: 00007f5ab7f81000 RCX: 0000000000000000 [13755.434352] RDX: 0000000000100000 RSI: 00007f5ab7f81000 RDI: 00007f5aba61c000 [13755.434355] RBP: 00007f5aba61c000 R08: 0000000000000007 R09: 0000000100000000 [13755.434359] R10: 000000000000037d R11: 00007f5ab91b5840 R12: 0000000000000001 [13755.434362] R13: 0000000000000005 R14: 0000000000000001 R15: 0000000000000000 and cyclic deadlocks: [ 2566.458979] ====================================================== [ 2566.459054] [ INFO: possible circular locking dependency detected ] [ 2566.459127] 4.11.0-rc1+ #26 Not tainted [ 2566.459194] ------------------------------------------------------- [ 2566.459266] gem_streaming_w/759 is trying to acquire lock: [ 2566.459334] (&obj->mm.lock){+.+.+.}, at: [<ffffffffa034bc80>] i915_gem_object_pin_pages+0x0/0xc0 [i915] [ 2566.459605] [ 2566.459605] but task is already holding lock: [ 2566.459699] (&mm->mmap_sem){++++++}, at: [<ffffffff8106fd11>] __do_page_fault+0x121/0x500 [ 2566.459814] [ 2566.459814] which lock already depends on the new lock. [ 2566.459814] [ 2566.459934] [ 2566.459934] the existing dependency chain (in reverse order) is: [ 2566.460030] [ 2566.460030] -> #1 (&mm->mmap_sem){++++++}: [ 2566.460139] lock_acquire+0xfe/0x220 [ 2566.460214] down_read+0x4e/0x90 [ 2566.460444] i915_gem_userptr_get_pages+0x6e/0x340 [i915] [ 2566.460669] ____i915_gem_object_get_pages+0x8b/0xd0 [i915] [ 2566.460900] __i915_gem_object_get_pages+0x6a/0x80 [i915] [ 2566.461132] __i915_vma_do_pin+0x7fa/0x930 [i915] [ 2566.461352] eb_add_vma+0x67b/0x830 [i915] [ 2566.461572] eb_lookup_vmas+0xafe/0x1010 [i915] [ 2566.461792] i915_gem_do_execbuffer+0x715/0x2870 [i915] [ 2566.462012] i915_gem_execbuffer2+0x106/0x2b0 [i915] [ 2566.462152] drm_ioctl+0x36c/0x670 [drm] [ 2566.462236] do_vfs_ioctl+0x12c/0xa60 [ 2566.462317] SyS_ioctl+0x41/0x70 [ 2566.462399] entry_SYSCALL_64_fastpath+0x1c/0xb1 [ 2566.462477] [ 2566.462477] -> #0 (&obj->mm.lock){+.+.+.}: [ 2566.462587] __lock_acquire+0x1602/0x1790 [ 2566.462661] lock_acquire+0xfe/0x220 [ 2566.462893] i915_gem_object_pin_pages+0x4c/0xc0 [i915] [ 2566.463116] i915_gem_fault+0x2c2/0x8c0 [i915] [ 2566.463197] __do_fault+0x42/0x130 [ 2566.463276] __handle_mm_fault+0x92c/0x1280 [ 2566.463356] handle_mm_fault+0x1e2/0x440 [ 2566.463443] __do_page_fault+0x1c4/0x500 [ 2566.463529] do_page_fault+0xc/0x10 [ 2566.463613] page_fault+0x1f/0x30 [ 2566.463693] [ 2566.463693] other info that might help us debug this: [ 2566.463693] [ 2566.463820] Possible unsafe locking scenario: [ 2566.463820] [ 2566.463918] CPU0 CPU1 [ 2566.463988] ---- ---- [ 2566.464068] lock(&mm->mmap_sem); [ 2566.464143] lock(&obj->mm.lock); [ 2566.464226] lock(&mm->mmap_sem); [ 2566.464304] lock(&obj->mm.lock); [ 2566.464378] [ 2566.464378] *** DEADLOCK *** [ 2566.464378] [ 2566.464504] 1 lock held by gem_streaming_w/759: [ 2566.464576] #0: (&mm->mmap_sem){++++++}, at: [<ffffffff8106fd11>] __do_page_fault+0x121/0x500 [ 2566.464699] [ 2566.464699] stack backtrace: [ 2566.464801] CPU: 0 PID: 759 Comm: gem_streaming_w Not tainted 4.11.0-rc1+ #26 [ 2566.464881] Hardware name: GIGABYTE GB-BXBT-1900/MZBAYAB-00, BIOS F8 03/02/2016 [ 2566.464983] Call Trace: [ 2566.465061] dump_stack+0x68/0x9f [ 2566.465144] print_circular_bug+0x20b/0x260 [ 2566.465234] __lock_acquire+0x1602/0x1790 [ 2566.465323] ? debug_check_no_locks_freed+0x1a0/0x1a0 [ 2566.465564] ? i915_gem_object_wait+0x238/0x650 [i915] [ 2566.465657] ? debug_lockdep_rcu_enabled.part.4+0x1a/0x30 [ 2566.465749] lock_acquire+0xfe/0x220 [ 2566.465985] ? i915_sg_trim+0x1b0/0x1b0 [i915] [ 2566.466223] i915_gem_object_pin_pages+0x4c/0xc0 [i915] [ 2566.466461] ? i915_sg_trim+0x1b0/0x1b0 [i915] [ 2566.466699] i915_gem_fault+0x2c2/0x8c0 [i915] [ 2566.466939] ? i915_gem_pwrite_ioctl+0xce0/0xce0 [i915] [ 2566.467030] ? __lock_acquire+0x642/0x1790 [ 2566.467122] ? __lock_acquire+0x642/0x1790 [ 2566.467209] ? debug_lockdep_rcu_enabled+0x35/0x40 [ 2566.467299] ? get_unmapped_area+0x1b4/0x1d0 [ 2566.467387] __do_fault+0x42/0x130 [ 2566.467474] __handle_mm_fault+0x92c/0x1280 [ 2566.467564] ? __pmd_alloc+0x1e0/0x1e0 [ 2566.467651] ? vm_mmap_pgoff+0x160/0x190 [ 2566.467740] ? handle_mm_fault+0x111/0x440 [ 2566.467827] handle_mm_fault+0x1e2/0x440 [ 2566.467914] ? handle_mm_fault+0x5d/0x440 [ 2566.468002] __do_page_fault+0x1c4/0x500 [ 2566.468090] do_page_fault+0xc/0x10 [ 2566.468180] page_fault+0x1f/0x30 [ 2566.468263] RIP: 0033:0x557895ced32a [ 2566.468337] RSP: 002b:00007fffd6dd8a10 EFLAGS: 00010202 [ 2566.468419] RAX: 00007f659a4db000 RBX: 0000000000000003 RCX: 00007f659ad032da [ 2566.468501] RDX: 0000000000000000 RSI: 0000000000100000 RDI: 0000000000000000 [ 2566.468586] RBP: 0000000000000007 R08: 0000000000000003 R09: 0000000100000000 [ 2566.468667] R10: 0000000000000001 R11: 0000000000000246 R12: 0000557895ceda60 [ 2566.468749] R13: 0000000000000001 R14: 00007fffd6dd8ac0 R15: 00007f659a4db000 By checking the status of the gup worker (serialized by the obj->mm.lock) we can determine whether it is still active, has failed or has succeeded. If the worker is still active (or failed), we know that it cannot be bound and so we can skip taking struct_mutex (risking potential recursion). As we check the worker status, we mark it to discard any partial results, forcing us to restart on the next get_pages. Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Fixes: 1c8782d ("drm/i915/userptr: Disallow wrapping GTT into a userptr") Testcase: igt/gem_userptr_blits/map-fixed-invalidate-gup Testcase: igt/gem_userptr_blits/dmabuf-sync Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michał Winiarski <michal.winiarski@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170315140150.19432-1-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
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Fengguang reported a KASAN warning: Kprobe smoke test: started ================================================================== BUG: KASAN: stack-out-of-bounds in deref_stack_reg+0xb5/0x11a Read of size 8 at addr ffff8800001c7cd8 by task swapper/1 CPU: 0 PID: 1 Comm: swapper Not tainted 4.14.0-rc8 #26 Call Trace: <#DB> ... save_trace+0xd9/0x1d3 mark_lock+0x5f7/0xdc3 __lock_acquire+0x6b4/0x38ef lock_acquire+0x1a1/0x2aa _raw_spin_lock_irqsave+0x46/0x55 kretprobe_table_lock+0x1a/0x42 pre_handler_kretprobe+0x3f5/0x521 kprobe_int3_handler+0x19c/0x25f do_int3+0x61/0x142 int3+0x30/0x60 [...] The ORC unwinder got confused by some kprobes changes, which isn't surprising since the runtime code no longer matches vmlinux and the stack was modified for kretprobes. Until we have a way for generated code to register changes with the unwinder, these types of warnings are inevitable. So just disable KASAN checks for stack accesses in the ORC unwinder. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20171108021934.zbl6unh5hpugybc5@treble Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Reported by syzkaller: *** Guest State *** CR0: actual=0x0000000080010031, shadow=0x0000000060000010, gh_mask=fffffffffffffff7 CR4: actual=0x0000000000002061, shadow=0x0000000000000000, gh_mask=ffffffffffffe8f1 CR3 = 0x000000002081e000 RSP = 0x000000000000fffa RIP = 0x0000000000000000 RFLAGS=0x00023000 DR7 = 0x00000000000000 ^^^^^^^^^^ ------------[ cut here ]------------ WARNING: CPU: 6 PID: 24431 at /home/kernel/linux/arch/x86/kvm//x86.c:7302 kvm_arch_vcpu_ioctl_run+0x651/0x2ea0 [kvm] CPU: 6 PID: 24431 Comm: reprotest Tainted: G W OE 4.14.0+ #26 RIP: 0010:kvm_arch_vcpu_ioctl_run+0x651/0x2ea0 [kvm] RSP: 0018:ffff880291d179e0 EFLAGS: 00010202 Call Trace: kvm_vcpu_ioctl+0x479/0x880 [kvm] do_vfs_ioctl+0x142/0x9a0 SyS_ioctl+0x74/0x80 entry_SYSCALL_64_fastpath+0x23/0x9a The failed vmentry is triggered by the following beautified testcase: #include <unistd.h> #include <sys/syscall.h> #include <string.h> #include <stdint.h> #include <linux/kvm.h> #include <fcntl.h> #include <sys/ioctl.h> long r[5]; int main() { struct kvm_debugregs dr = { 0 }; r[2] = open("/dev/kvm", O_RDONLY); r[3] = ioctl(r[2], KVM_CREATE_VM, 0); r[4] = ioctl(r[3], KVM_CREATE_VCPU, 7); struct kvm_guest_debug debug = { .control = 0xf0403, .arch = { .debugreg[6] = 0x2, .debugreg[7] = 0x2 } }; ioctl(r[4], KVM_SET_GUEST_DEBUG, &debug); ioctl(r[4], KVM_RUN, 0); } which testcase tries to setup the processor specific debug registers and configure vCPU for handling guest debug events through KVM_SET_GUEST_DEBUG. The KVM_SET_GUEST_DEBUG ioctl will get and set rflags in order to set TF bit if single step is needed. All regs' caches are reset to avail and GUEST_RFLAGS vmcs field is reset to 0x2 during vCPU reset. However, the cache of rflags is not reset during vCPU reset. The function vmx_get_rflags() returns an unreset rflags cache value since the cache is marked avail, it is 0 after boot. Vmentry fails if the rflags reserved bit 1 is 0. This patch fixes it by resetting both the GUEST_RFLAGS vmcs field and its cache to 0x2 during vCPU reset. Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Reported by syzkaller: ------------[ cut here ]------------ WARNING: CPU: 5 PID: 2939 at arch/x86/kvm/vmx.c:3844 free_loaded_vmcs+0x77/0x80 [kvm_intel] CPU: 5 PID: 2939 Comm: repro Not tainted 4.14.0+ #26 RIP: 0010:free_loaded_vmcs+0x77/0x80 [kvm_intel] Call Trace: vmx_free_vcpu+0xda/0x130 [kvm_intel] kvm_arch_destroy_vm+0x192/0x290 [kvm] kvm_put_kvm+0x262/0x560 [kvm] kvm_vm_release+0x2c/0x30 [kvm] __fput+0x190/0x370 task_work_run+0xa1/0xd0 do_exit+0x4d2/0x13e0 do_group_exit+0x89/0x140 get_signal+0x318/0xb80 do_signal+0x8c/0xb40 exit_to_usermode_loop+0xe4/0x140 syscall_return_slowpath+0x206/0x230 entry_SYSCALL_64_fastpath+0x98/0x9a The syzkaller testcase will execute VMXON/VMLAUCH instructions, so the vmx->nested stuff is populated, it will also issue KVM_SMI ioctl. However, the testcase is just a simple c program and not be lauched by something like seabios which implements smi_handler. Commit 05cade7 (KVM: nSVM: fix SMI injection in guest mode) gets out of guest mode and set nested.vmxon to false for the duration of SMM according to SDM 34.14.1 "leave VMX operation" upon entering SMM. We can't alloc/free the vmx->nested stuff each time when entering/exiting SMM since it will induce more overhead. So the function vmx_pre_enter_smm() marks nested.vmxon false even if vmx->nested stuff is still populated. What it expected is em_rsm() can mark nested.vmxon to be true again. However, the smi_handler/rsm will not execute since there is no something like seabios in this scenario. The function free_nested() fails to free the vmx->nested stuff since the vmx->nested.vmxon is false which results in the above warning. This patch fixes it by also considering the no SMI handler case, luckily vmx->nested.smm.vmxon is marked according to the value of vmx->nested.vmxon in vmx_pre_enter_smm(), we can take advantage of it and free vmx->nested stuff when L1 goes down. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Fixes: 05cade7 (KVM: nSVM: fix SMI injection in guest mode) Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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In rsa_get_n(), if the buffer contained all 0's and "FIPS mode" is enabled, we would read one byte past the end of the buffer while scanning the leading zeroes. Fix it by checking 'n_sz' before '!*ptr'. This bug was reachable by adding a specially crafted key of type "asymmetric" (requires CONFIG_RSA and CONFIG_X509_CERTIFICATE_PARSER). KASAN report: BUG: KASAN: slab-out-of-bounds in rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33 Read of size 1 at addr ffff88003501a708 by task keyctl/196 CPU: 1 PID: 196 Comm: keyctl Not tainted 4.14.0-09238-g1d3b78bbc6e9 #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 Call Trace: rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33 asn1_ber_decoder+0x82a/0x1fd0 lib/asn1_decoder.c:328 rsa_set_pub_key+0xd3/0x320 crypto/rsa.c:278 crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline] pkcs1pad_set_pub_key+0xae/0x200 crypto/rsa-pkcs1pad.c:117 crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline] public_key_verify_signature+0x270/0x9d0 crypto/asymmetric_keys/public_key.c:106 x509_check_for_self_signed+0x2ea/0x480 crypto/asymmetric_keys/x509_public_key.c:141 x509_cert_parse+0x46a/0x620 crypto/asymmetric_keys/x509_cert_parser.c:129 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Allocated by task 196: __do_kmalloc mm/slab.c:3711 [inline] __kmalloc_track_caller+0x118/0x2e0 mm/slab.c:3726 kmemdup+0x17/0x40 mm/util.c:118 kmemdup ./include/linux/string.h:414 [inline] x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Fixes: 5a7de97 ("crypto: rsa - return raw integers for the ASN.1 parser") Cc: <stable@vger.kernel.org> # v4.8+ Cc: Tudor Ambarus <tudor-dan.ambarus@nxp.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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In asn1_ber_decoder(), indefinitely-sized ASN.1 items were being passed to the action functions before their lengths had been computed, using the bogus length of 0x80 (ASN1_INDEFINITE_LENGTH). This resulted in reading data past the end of the input buffer, when given a specially crafted message. Fix it by rearranging the code so that the indefinite length is resolved before the action is called. This bug was originally found by fuzzing the X.509 parser in userspace using libFuzzer from the LLVM project. KASAN report (cleaned up slightly): BUG: KASAN: slab-out-of-bounds in memcpy ./include/linux/string.h:341 [inline] BUG: KASAN: slab-out-of-bounds in x509_fabricate_name.constprop.1+0x1a4/0x940 crypto/asymmetric_keys/x509_cert_parser.c:366 Read of size 128 at addr ffff880035dd9eaf by task keyctl/195 CPU: 1 PID: 195 Comm: keyctl Not tainted 4.14.0-09238-g1d3b78bbc6e9 #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xd1/0x175 lib/dump_stack.c:53 print_address_description+0x78/0x260 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x23f/0x350 mm/kasan/report.c:409 memcpy+0x1f/0x50 mm/kasan/kasan.c:302 memcpy ./include/linux/string.h:341 [inline] x509_fabricate_name.constprop.1+0x1a4/0x940 crypto/asymmetric_keys/x509_cert_parser.c:366 asn1_ber_decoder+0xb4a/0x1fd0 lib/asn1_decoder.c:447 x509_cert_parse+0x1c7/0x620 crypto/asymmetric_keys/x509_cert_parser.c:89 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Allocated by task 195: __do_kmalloc_node mm/slab.c:3675 [inline] __kmalloc_node+0x47/0x60 mm/slab.c:3682 kvmalloc ./include/linux/mm.h:540 [inline] SYSC_add_key security/keys/keyctl.c:104 [inline] SyS_add_key+0x19e/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Fixes: 42d5ec2 ("X.509: Add an ASN.1 decoder") Reported-by: Alexander Potapenko <glider@google.com> Cc: <stable@vger.kernel.org> # v3.7+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
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Jan 6, 2018
Adding a specially crafted X.509 certificate whose subjectPublicKey ASN.1 value is zero-length caused x509_extract_key_data() to set the public key size to SIZE_MAX, as it subtracted the nonexistent BIT STRING metadata byte. Then, x509_cert_parse() called kmemdup() with that bogus size, triggering the WARN_ON_ONCE() in kmalloc_slab(). This appears to be harmless, but it still must be fixed since WARNs are never supposed to be user-triggerable. Fix it by updating x509_cert_parse() to validate that the value has a BIT STRING metadata byte, and that the byte is 0 which indicates that the number of bits in the bitstring is a multiple of 8. It would be nice to handle the metadata byte in asn1_ber_decoder() instead. But that would be tricky because in the general case a BIT STRING could be implicitly tagged, and/or could legitimately have a length that is not a whole number of bytes. Here was the WARN (cleaned up slightly): WARNING: CPU: 1 PID: 202 at mm/slab_common.c:971 kmalloc_slab+0x5d/0x70 mm/slab_common.c:971 Modules linked in: CPU: 1 PID: 202 Comm: keyctl Tainted: G B 4.14.0-09238-g1d3b78bbc6e9 #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 task: ffff880033014180 task.stack: ffff8800305c8000 Call Trace: __do_kmalloc mm/slab.c:3706 [inline] __kmalloc_track_caller+0x22/0x2e0 mm/slab.c:3726 kmemdup+0x17/0x40 mm/util.c:118 kmemdup include/linux/string.h:414 [inline] x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Fixes: 42d5ec2 ("X.509: Add an ASN.1 decoder") Cc: <stable@vger.kernel.org> # v3.7+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com>
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Jan 17, 2018
commit e0058f3 upstream. In asn1_ber_decoder(), indefinitely-sized ASN.1 items were being passed to the action functions before their lengths had been computed, using the bogus length of 0x80 (ASN1_INDEFINITE_LENGTH). This resulted in reading data past the end of the input buffer, when given a specially crafted message. Fix it by rearranging the code so that the indefinite length is resolved before the action is called. This bug was originally found by fuzzing the X.509 parser in userspace using libFuzzer from the LLVM project. KASAN report (cleaned up slightly): BUG: KASAN: slab-out-of-bounds in memcpy ./include/linux/string.h:341 [inline] BUG: KASAN: slab-out-of-bounds in x509_fabricate_name.constprop.1+0x1a4/0x940 crypto/asymmetric_keys/x509_cert_parser.c:366 Read of size 128 at addr ffff880035dd9eaf by task keyctl/195 CPU: 1 PID: 195 Comm: keyctl Not tainted 4.14.0-09238-g1d3b78bbc6e9 #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xd1/0x175 lib/dump_stack.c:53 print_address_description+0x78/0x260 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x23f/0x350 mm/kasan/report.c:409 memcpy+0x1f/0x50 mm/kasan/kasan.c:302 memcpy ./include/linux/string.h:341 [inline] x509_fabricate_name.constprop.1+0x1a4/0x940 crypto/asymmetric_keys/x509_cert_parser.c:366 asn1_ber_decoder+0xb4a/0x1fd0 lib/asn1_decoder.c:447 x509_cert_parse+0x1c7/0x620 crypto/asymmetric_keys/x509_cert_parser.c:89 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Allocated by task 195: __do_kmalloc_node mm/slab.c:3675 [inline] __kmalloc_node+0x47/0x60 mm/slab.c:3682 kvmalloc ./include/linux/mm.h:540 [inline] SYSC_add_key security/keys/keyctl.c:104 [inline] SyS_add_key+0x19e/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Fixes: 42d5ec2 ("X.509: Add an ASN.1 decoder") Reported-by: Alexander Potapenko <glider@google.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Jan 17, 2018
commit 0f30cbe upstream. Adding a specially crafted X.509 certificate whose subjectPublicKey ASN.1 value is zero-length caused x509_extract_key_data() to set the public key size to SIZE_MAX, as it subtracted the nonexistent BIT STRING metadata byte. Then, x509_cert_parse() called kmemdup() with that bogus size, triggering the WARN_ON_ONCE() in kmalloc_slab(). This appears to be harmless, but it still must be fixed since WARNs are never supposed to be user-triggerable. Fix it by updating x509_cert_parse() to validate that the value has a BIT STRING metadata byte, and that the byte is 0 which indicates that the number of bits in the bitstring is a multiple of 8. It would be nice to handle the metadata byte in asn1_ber_decoder() instead. But that would be tricky because in the general case a BIT STRING could be implicitly tagged, and/or could legitimately have a length that is not a whole number of bytes. Here was the WARN (cleaned up slightly): WARNING: CPU: 1 PID: 202 at mm/slab_common.c:971 kmalloc_slab+0x5d/0x70 mm/slab_common.c:971 Modules linked in: CPU: 1 PID: 202 Comm: keyctl Tainted: G B 4.14.0-09238-g1d3b78bbc6e9 #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 task: ffff880033014180 task.stack: ffff8800305c8000 Call Trace: __do_kmalloc mm/slab.c:3706 [inline] __kmalloc_track_caller+0x22/0x2e0 mm/slab.c:3726 kmemdup+0x17/0x40 mm/util.c:118 kmemdup include/linux/string.h:414 [inline] x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Fixes: 42d5ec2 ("X.509: Add an ASN.1 decoder") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Jan 17, 2018
commit d2890c3 upstream. In rsa_get_n(), if the buffer contained all 0's and "FIPS mode" is enabled, we would read one byte past the end of the buffer while scanning the leading zeroes. Fix it by checking 'n_sz' before '!*ptr'. This bug was reachable by adding a specially crafted key of type "asymmetric" (requires CONFIG_RSA and CONFIG_X509_CERTIFICATE_PARSER). KASAN report: BUG: KASAN: slab-out-of-bounds in rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33 Read of size 1 at addr ffff88003501a708 by task keyctl/196 CPU: 1 PID: 196 Comm: keyctl Not tainted 4.14.0-09238-g1d3b78bbc6e9 #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 Call Trace: rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33 asn1_ber_decoder+0x82a/0x1fd0 lib/asn1_decoder.c:328 rsa_set_pub_key+0xd3/0x320 crypto/rsa.c:278 crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline] pkcs1pad_set_pub_key+0xae/0x200 crypto/rsa-pkcs1pad.c:117 crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline] public_key_verify_signature+0x270/0x9d0 crypto/asymmetric_keys/public_key.c:106 x509_check_for_self_signed+0x2ea/0x480 crypto/asymmetric_keys/x509_public_key.c:141 x509_cert_parse+0x46a/0x620 crypto/asymmetric_keys/x509_cert_parser.c:129 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Allocated by task 196: __do_kmalloc mm/slab.c:3711 [inline] __kmalloc_track_caller+0x118/0x2e0 mm/slab.c:3726 kmemdup+0x17/0x40 mm/util.c:118 kmemdup ./include/linux/string.h:414 [inline] x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106 x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0x96 Fixes: 5a7de97 ("crypto: rsa - return raw integers for the ASN.1 parser") Cc: Tudor Ambarus <tudor-dan.ambarus@nxp.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Feb 5, 2018
[ Upstream commit c37c287 ] Reported by syzkaller: *** Guest State *** CR0: actual=0x0000000080010031, shadow=0x0000000060000010, gh_mask=fffffffffffffff7 CR4: actual=0x0000000000002061, shadow=0x0000000000000000, gh_mask=ffffffffffffe8f1 CR3 = 0x000000002081e000 RSP = 0x000000000000fffa RIP = 0x0000000000000000 RFLAGS=0x00023000 DR7 = 0x00000000000000 ^^^^^^^^^^ ------------[ cut here ]------------ WARNING: CPU: 6 PID: 24431 at /home/kernel/linux/arch/x86/kvm//x86.c:7302 kvm_arch_vcpu_ioctl_run+0x651/0x2ea0 [kvm] CPU: 6 PID: 24431 Comm: reprotest Tainted: G W OE 4.14.0+ #26 RIP: 0010:kvm_arch_vcpu_ioctl_run+0x651/0x2ea0 [kvm] RSP: 0018:ffff880291d179e0 EFLAGS: 00010202 Call Trace: kvm_vcpu_ioctl+0x479/0x880 [kvm] do_vfs_ioctl+0x142/0x9a0 SyS_ioctl+0x74/0x80 entry_SYSCALL_64_fastpath+0x23/0x9a The failed vmentry is triggered by the following beautified testcase: #include <unistd.h> #include <sys/syscall.h> #include <string.h> #include <stdint.h> #include <linux/kvm.h> #include <fcntl.h> #include <sys/ioctl.h> long r[5]; int main() { struct kvm_debugregs dr = { 0 }; r[2] = open("/dev/kvm", O_RDONLY); r[3] = ioctl(r[2], KVM_CREATE_VM, 0); r[4] = ioctl(r[3], KVM_CREATE_VCPU, 7); struct kvm_guest_debug debug = { .control = 0xf0403, .arch = { .debugreg[6] = 0x2, .debugreg[7] = 0x2 } }; ioctl(r[4], KVM_SET_GUEST_DEBUG, &debug); ioctl(r[4], KVM_RUN, 0); } which testcase tries to setup the processor specific debug registers and configure vCPU for handling guest debug events through KVM_SET_GUEST_DEBUG. The KVM_SET_GUEST_DEBUG ioctl will get and set rflags in order to set TF bit if single step is needed. All regs' caches are reset to avail and GUEST_RFLAGS vmcs field is reset to 0x2 during vCPU reset. However, the cache of rflags is not reset during vCPU reset. The function vmx_get_rflags() returns an unreset rflags cache value since the cache is marked avail, it is 0 after boot. Vmentry fails if the rflags reserved bit 1 is 0. This patch fixes it by resetting both the GUEST_RFLAGS vmcs field and its cache to 0x2 during vCPU reset. Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Mar 9, 2018
[ Upstream commit e2d5915 ] The hotplug code uses its own workqueue to handle IRQ requests (pseries_hp_wq), however that workqueue is initialized after init_ras_IRQ(). That can lead to a kernel panic if any hotplug interrupts fire after init_ras_IRQ() but before pseries_hp_wq is initialised. eg: UDP-Lite hash table entries: 2048 (order: 0, 65536 bytes) NET: Registered protocol family 1 Unpacking initramfs... (qemu) object_add memory-backend-ram,id=mem1,size=10G (qemu) device_add pc-dimm,id=dimm1,memdev=mem1 Unable to handle kernel paging request for data at address 0xf94d03007c421378 Faulting instruction address: 0xc00000000012d744 Oops: Kernel access of bad area, sig: 11 [#1] LE SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc2-ziviani+ #26 task: (ptrval) task.stack: (ptrval) NIP: c00000000012d744 LR: c00000000012d744 CTR: 0000000000000000 REGS: (ptrval) TRAP: 0380 Not tainted (4.15.0-rc2-ziviani+) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 28088042 XER: 20040000 CFAR: c00000000012d3c4 SOFTE: 0 ... NIP [c00000000012d744] __queue_work+0xd4/0x5c0 LR [c00000000012d744] __queue_work+0xd4/0x5c0 Call Trace: [c0000000fffefb90] [c00000000012d744] __queue_work+0xd4/0x5c0 (unreliable) [c0000000fffefc70] [c00000000012dce4] queue_work_on+0xb4/0xf0 This commit makes the RAS IRQ registration explicitly dependent on the creation of the pseries_hp_wq. Reported-by: Min Deng <mdeng@redhat.com> Reported-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com> Tested-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Apr 17, 2018
[ Upstream commit ebe2f87 ] The ACPI specification says OS shouldn't attempt to use GICC configuration parameters if the flag ACPI_MADT_ENABLED is cleared. The ARM64-SMP code skips the disabled GICC entries but not causing any issue. However the current GICv3 driver probe bails out causing kernel panic() instead of skipping the disabled GICC interfaces. This issue happens on systems where redistributor regions are not in the always-on power domain and one of GICC interface marked with ACPI_MADT_ENABLED=0. This patch does the two things to fix the panic. - Don't return an error in gic_acpi_match_gicc() for disabled GICC entry. - No need to keep GICR region information for disabled GICC entry. Observed kernel crash on QDF2400 platform GICC entry is disabled. Kernel crash traces: Kernel panic - not syncing: No interrupt controller found. CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.13.5 #26 [<ffff000008087770>] dump_backtrace+0x0/0x218 [<ffff0000080879dc>] show_stack+0x14/0x20 [<ffff00000883b078>] dump_stack+0x98/0xb8 [<ffff0000080c5c14>] panic+0x118/0x26c [<ffff000008b62348>] init_IRQ+0x24/0x2c [<ffff000008b609fc>] start_kernel+0x230/0x394 [<ffff000008b601e4>] __primary_switched+0x64/0x6c ---[ end Kernel panic - not syncing: No interrupt controller found. Disabled GICC subtable example: Subtable Type : 0B [Generic Interrupt Controller] Length : 50 Reserved : 0000 CPU Interface Number : 0000003D Processor UID : 0000003D Flags (decoded below) : 00000000 Processor Enabled : 0 Performance Interrupt Trig Mode : 0 Virtual GIC Interrupt Trig Mode : 0 Parking Protocol Version : 00000000 Performance Interrupt : 00000017 Parked Address : 0000000000000000 Base Address : 0000000000000000 Virtual GIC Base Address : 0000000000000000 Hypervisor GIC Base Address : 0000000000000000 Virtual GIC Interrupt : 00000019 Redistributor Base Address : 0000FFFF88F40000 ARM MPIDR : 000000000000000D Efficiency Class : 00 Reserved : 000000 Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Sorry for my ignorance, but it seems that the VC4 drivers doesn't work quite properly together with pluggable USB display devices, or maybe this is an issue with Xorg.
I used a Raspberry PI2 + Lenovo LT1412 , but I guess it should do any other USB display. Without the option "experimental GL driver for desktop" it works quite well, but no OpenGL output on X.
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