- 27 Aug, 2016 9 commits
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Martin Willi authored
commit 62397da5 upstream. A wmediumd that does not send this attribute causes a NULL pointer dereference, as the attribute is accessed even if it does not exist. The attribute was required but never checked ever since userspace frame forwarding has been introduced. The issue gets more problematic once we allow wmediumd registration from user namespaces. Fixes: 7882513b ("mac80211_hwsim driver support userspace frame tx/rx") Signed-off-by:
Martin Willi <martin@strongswan.org> Signed-off-by:
Johannes Berg <johannes.berg@intel.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
Willy Tarreau <w@1wt.eu>
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Bob Copeland authored
commit fe7a7c57 upstream. Currently, the mesh paths associated with a nexthop station are cleaned up in the following code path: __sta_info_destroy_part1 synchronize_net() __sta_info_destroy_part2 -> cleanup_single_sta -> mesh_sta_cleanup -> mesh_plink_deactivate -> mesh_path_flush_by_nexthop However, there are a couple of problems here: 1) the paths aren't flushed at all if the MPM is running in userspace (e.g. when using wpa_supplicant or authsae) 2) there is no synchronize_rcu between removing the path and readers accessing the nexthop, which means the following race is possible: CPU0 CPU1 ~~~~ ~~~~ sta_info_destroy_part1() synchronize_net() rcu_read_lock() mesh_nexthop_resolve() mpath = mesh_path_lookup() [...] -> mesh_path_flush_by_nexthop() sta = rcu_dereference( mpath->next_hop) kfree(sta) access sta <-- CRASH Fix both of these by unconditionally flushing paths before destroying the sta, and by adding a synchronize_net() after path flush to ensure no active readers can still dereference the sta. Fixes this crash: [ 348.529295] BUG: unable to handle kernel paging request at 00020040 [ 348.530014] IP: [<f929245d>] ieee80211_mps_set_frame_flags+0x40/0xaa [mac80211] [ 348.530014] *pde = 00000000 [ 348.530014] Oops: 0000 [#1] PREEMPT [ 348.530014] Modules linked in: drbg ansi_cprng ctr ccm ppp_generic slhc ipt_MASQUERADE nf_nat_masquerade_ipv4 8021q ] [ 348.530014] CPU: 0 PID: 20597 Comm: wget Tainted: G O 4.6.0-rc5-wt=V1 #1 [ 348.530014] Hardware name: To Be Filled By O.E.M./To be filled by O.E.M., BIOS 080016 11/07/2014 [ 348.530014] task: f64fa280 ti: f4f9c000 task.ti: f4f9c000 [ 348.530014] EIP: 0060:[<f929245d>] EFLAGS: 00010246 CPU: 0 [ 348.530014] EIP is at ieee80211_mps_set_frame_flags+0x40/0xaa [mac80211] [ 348.530014] EAX: f4ce63e0 EBX: 00000088 ECX: f3788416 EDX: 00020008 [ 348.530014] ESI: 00000000 EDI: 00000088 EBP: f6409a4c ESP: f6409a40 [ 348.530014] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [ 348.530014] CR0: 80050033 CR2: 00020040 CR3: 33190000 CR4: 00000690 [ 348.530014] Stack: [ 348.530014] 00000000 f4ce63e0 f5f9bd80 f6409a64 f9291d80 0000ce67 f5d51e00 f4ce63e0 [ 348.530014] f3788416 f6409a80 f9291dc1 f4ce8320 f4ce63e0 f5d51e00 f4ce63e0 f4ce8320 [ 348.530014] f6409a98 f9277f6f 00000000 00000000 0000007c 00000000 f6409b2c f9278dd1 [ 348.530014] Call Trace: [ 348.530014] [<f9291d80>] mesh_nexthop_lookup+0xbb/0xc8 [mac80211] [ 348.530014] [<f9291dc1>] mesh_nexthop_resolve+0x34/0xd8 [mac80211] [ 348.530014] [<f9277f6f>] ieee80211_xmit+0x92/0xc1 [mac80211] [ 348.530014] [<f9278dd1>] __ieee80211_subif_start_xmit+0x807/0x83c [mac80211] [ 348.530014] [<c04df012>] ? sch_direct_xmit+0xd7/0x1b3 [ 348.530014] [<c022a8c6>] ? __local_bh_enable_ip+0x5d/0x7b [ 348.530014] [<f956870c>] ? nf_nat_ipv4_out+0x4c/0xd0 [nf_nat_ipv4] [ 348.530014] [<f957e036>] ? iptable_nat_ipv4_fn+0xf/0xf [iptable_nat] [ 348.530014] [<c04c6f45>] ? netif_skb_features+0x14d/0x30a [ 348.530014] [<f9278e10>] ieee80211_subif_start_xmit+0xa/0xe [mac80211] [ 348.530014] [<c04c769c>] dev_hard_start_xmit+0x1f8/0x267 [ 348.530014] [<c04c7261>] ? validate_xmit_skb.isra.120.part.121+0x10/0x253 [ 348.530014] [<c04defc6>] sch_direct_xmit+0x8b/0x1b3 [ 348.530014] [<c04c7a9c>] __dev_queue_xmit+0x2c8/0x513 [ 348.530014] [<c04c7cfb>] dev_queue_xmit+0xa/0xc [ 348.530014] [<f91bfc7a>] batadv_send_skb_packet+0xd6/0xec [batman_adv] [ 348.530014] [<f91bfdc4>] batadv_send_unicast_skb+0x15/0x4a [batman_adv] [ 348.530014] [<f91b5938>] batadv_dat_send_data+0x27e/0x310 [batman_adv] [ 348.530014] [<f91c30b5>] ? batadv_tt_global_hash_find.isra.11+0x8/0xa [batman_adv] [ 348.530014] [<f91b63f3>] batadv_dat_snoop_outgoing_arp_request+0x208/0x23d [batman_adv] [ 348.530014] [<f91c0cd9>] batadv_interface_tx+0x206/0x385 [batman_adv] [ 348.530014] [<c04c769c>] dev_hard_start_xmit+0x1f8/0x267 [ 348.530014] [<c04c7261>] ? validate_xmit_skb.isra.120.part.121+0x10/0x253 [ 348.530014] [<c04defc6>] sch_direct_xmit+0x8b/0x1b3 [ 348.530014] [<c04c7a9c>] __dev_queue_xmit+0x2c8/0x513 [ 348.530014] [<f80cbd2a>] ? igb_xmit_frame+0x57/0x72 [igb] [ 348.530014] [<c04c7cfb>] dev_queue_xmit+0xa/0xc [ 348.530014] [<f843a326>] br_dev_queue_push_xmit+0xeb/0xfb [bridge] [ 348.530014] [<f843a35f>] br_forward_finish+0x29/0x74 [bridge] [ 348.530014] [<f843a23b>] ? deliver_clone+0x3b/0x3b [bridge] [ 348.530014] [<f843a714>] __br_forward+0x89/0xe7 [bridge] [ 348.530014] [<f843a336>] ? br_dev_queue_push_xmit+0xfb/0xfb [bridge] [ 348.530014] [<f843a234>] deliver_clone+0x34/0x3b [bridge] [ 348.530014] [<f843a68b>] ? br_flood+0x95/0x95 [bridge] [ 348.530014] [<f843a66d>] br_flood+0x77/0x95 [bridge] [ 348.530014] [<f843a809>] br_flood_forward+0x13/0x1a [bridge] [ 348.530014] [<f843a68b>] ? br_flood+0x95/0x95 [bridge] [ 348.530014] [<f843b877>] br_handle_frame_finish+0x392/0x3db [bridge] [ 348.530014] [<c04e9b2b>] ? nf_iterate+0x2b/0x6b [ 348.530014] [<f843baa6>] br_handle_frame+0x1e6/0x240 [bridge] [ 348.530014] [<f843b4e5>] ? br_handle_local_finish+0x6a/0x6a [bridge] [ 348.530014] [<c04c4ba0>] __netif_receive_skb_core+0x43a/0x66b [ 348.530014] [<f843b8c0>] ? br_handle_frame_finish+0x3db/0x3db [bridge] [ 348.530014] [<c023cea4>] ? resched_curr+0x19/0x37 [ 348.530014] [<c0240707>] ? check_preempt_wakeup+0xbf/0xfe [ 348.530014] [<c0255dec>] ? ktime_get_with_offset+0x5c/0xfc [ 348.530014] [<c04c4fc1>] __netif_receive_skb+0x47/0x55 [ 348.530014] [<c04c57ba>] netif_receive_skb_internal+0x40/0x5a [ 348.530014] [<c04c61ef>] napi_gro_receive+0x3a/0x94 [ 348.530014] [<f80ce8d5>] igb_poll+0x6fd/0x9ad [igb] [ 348.530014] [<c0242bd8>] ? swake_up_locked+0x14/0x26 [ 348.530014] [<c04c5d29>] net_rx_action+0xde/0x250 [ 348.530014] [<c022a743>] __do_softirq+0x8a/0x163 [ 348.530014] [<c022a6b9>] ? __hrtimer_tasklet_trampoline+0x19/0x19 [ 348.530014] [<c021100f>] do_softirq_own_stack+0x26/0x2c [ 348.530014] <IRQ> [ 348.530014] [<c022a957>] irq_exit+0x31/0x6f [ 348.530014] [<c0210eb2>] do_IRQ+0x8d/0xa0 [ 348.530014] [<c058152c>] common_interrupt+0x2c/0x40 [ 348.530014] Code: e7 8c 00 66 81 ff 88 00 75 12 85 d2 75 0e b2 c3 b8 83 e9 29 f9 e8 a7 5f f9 c6 eb 74 66 81 e3 8c 005 [ 348.530014] EIP: [<f929245d>] ieee80211_mps_set_frame_flags+0x40/0xaa [mac80211] SS:ESP 0068:f6409a40 [ 348.530014] CR2: 0000000000020040 [ 348.530014] ---[ end trace 48556ac26779732e ]--- [ 348.530014] Kernel panic - not syncing: Fatal exception in interrupt [ 348.530014] Kernel Offset: disabled Reported-by:
Fred Veldini <fred.veldini@gmail.com> Tested-by:
Bob Copeland <me@bobcopeland.com> Signed-off-by:
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Feng Tang authored
commit 881d0327 upstream. Note: This is a verified backported patch for stable 4.4 kernel, and it could also be applied to 4.3/4.2/4.1/3.18/3.16 There is a problem with alx devices, that the network link will be lost in 1-5 minutes after the device is up. >From debugging without datasheet, we found the error always happen when the DMA RX address is set to 0x....fc0, which is very likely to be a HW/silicon problem. This patch will apply rx skb with 64 bytes longer space, and if the allocated skb has a 0x...fc0 address, it will use skb_resever(skb, 64) to advance the address, so that the RX overflow can be avoided. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=70761Signed-off-by:
Feng Tang <feng.tang@intel.com> Suggested-by:
Eric Dumazet <edumazet@google.com> Tested-by:
Ole Lukoie <olelukoie@mail.ru> Signed-off-by:
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Tom Goff authored
commit 70a0dec4 upstream. This fixes wrong-interface signaling on 32-bit platforms for entries created when jiffies > 2^31 + MFC_ASSERT_THRESH. Signed-off-by:
Tom Goff <thomas.goff@ll.mit.edu> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
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Simon Horman authored
commit d5d8760b upstream. Since 32b8a8e5 ("sit: add IPv4 over IPv4 support") ipip6_err() may be called for packets whose IP protocol is IPPROTO_IPIP as well as those whose IP protocol is IPPROTO_IPV6. In the case of IPPROTO_IPIP packets the correct protocol value is not passed to ipv4_update_pmtu() or ipv4_redirect(). This patch resolves this problem by using the IP protocol of the packet rather than a hard-coded value. This appears to be consistent with the usage of the protocol of a packet by icmp_socket_deliver() the caller of ipip6_err(). I was able to exercise the redirect case by using a setup where an ICMP redirect was received for the destination of the encapsulated packet. However, it appears that although incorrect the protocol field is not used in this case and thus no problem manifests. On inspection it does not appear that a problem will manifest in the fragmentation needed/update pmtu case either. In short I believe this is a cosmetic fix. None the less, the use of IPPROTO_IPV6 seems wrong and confusing. Reviewed-by:
Dinan Gunawardena <dinan.gunawardena@netronome.com> Signed-off-by:
Simon Horman <simon.horman@netronome.com> Acked-by:
YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by:
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Herbert Xu authored
commit 5f070e81 upstream. When there is more data to be processed, the current test in scatterwalk_done may prevent us from calling pagedone even when we should. In particular, if we're on an SG entry spanning multiple pages where the last page is not a full page, we will incorrectly skip calling pagedone on the second last page. This patch fixes this by adding a separate test for whether we've reached the end of a page. Cc: stable@vger.kernel.org Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
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Herbert Xu authored
commit b30bdfa8 upstream. As it is if you ask for a sync gcm you may actually end up with an async one because it does not filter out async implementations of ghash. This patch fixes this by adding the necessary filter when looking for ghash. Signed-off-by:
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Linus Walleij authored
commit 19ced623 upstream. The hash buffer is really HASH_BLOCK_SIZE bytes, someone must have thought that memmove takes n*u32 words by mistake. Tests work as good/bad as before after this patch. Cc: Joakim Bech <joakim.bech@linaro.org> Cc: stable@vger.kernel.org Reported-by:
David Binderman <linuxdev.baldrick@gmail.com> Signed-off-by:
Linus Walleij <linus.walleij@linaro.org> Signed-off-by:
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Al Viro authored
commit 3d56c25e upstream. Ascend-to-parent logics in d_walk() depends on all encountered child dentries not getting freed without an RCU delay. Unfortunately, in quite a few cases it is not true, with hard-to-hit oopsable race as the result. Fortunately, the fix is simiple; right now the rule is "if it ever been hashed, freeing must be delayed" and changing it to "if it ever had a parent, freeing must be delayed" closes that hole and covers all cases the old rule used to cover. Moreover, pipes and sockets remain _not_ covered, so we do not introduce RCU delay in the cases which are the reason for having that delay conditional in the first place. Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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- 22 Aug, 2016 8 commits
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Jann Horn authored
commit 2f36db71 upstream. This prevents users from triggering a stack overflow through a recursive invocation of pagefault handling that involves mapping procfs files into virtual memory. Signed-off-by:
Jann Horn <jannh@google.com> Acked-by:
Tyler Hicks <tyhicks@canonical.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Helge Deller authored
commit 8b78f260 upstream. One of the debian buildd servers had this crash in the syslog without any other information: Unaligned handler failed, ret = -2 clock_adjtime (pid 22578): Unaligned data reference (code 28) CPU: 1 PID: 22578 Comm: clock_adjtime Tainted: G E 4.5.0-2-parisc64-smp #1 Debian 4.5.4-1 task: 000000007d9960f8 ti: 00000001bde7c000 task.ti: 00000001bde7c000 YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI PSW: 00001000000001001111100000001111 Tainted: G E r00-03 000000ff0804f80f 00000001bde7c2b0 00000000402d2be8 00000001bde7c2b0 r04-07 00000000409e1fd0 00000000fa6f7fff 00000001bde7c148 00000000fa6f7fff r08-11 0000000000000000 00000000ffffffff 00000000fac9bb7b 000000000002b4d4 r12-15 000000000015241c 000000000015242c 000000000000002d 00000000fac9bb7b r16-19 0000000000028800 0000000000000001 0000000000000070 00000001bde7c218 r20-23 0000000000000000 00000001bde7c210 0000000000000002 0000000000000000 r24-27 0000000000000000 0000000000000000 00000001bde7c148 00000000409e1fd0 r28-31 0000000000000001 00000001bde7c320 00000001bde7c350 00000001bde7c218 sr00-03 0000000001200000 0000000001200000 0000000000000000 0000000001200000 sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000 IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000402d2e84 00000000402d2e88 IIR: 0ca0d089 ISR: 0000000001200000 IOR: 00000000fa6f7fff CPU: 1 CR30: 00000001bde7c000 CR31: ffffffffffffffff ORIG_R28: 00000002369fe628 IAOQ[0]: compat_get_timex+0x2dc/0x3c0 IAOQ[1]: compat_get_timex+0x2e0/0x3c0 RP(r2): compat_get_timex+0x40/0x3c0 Backtrace: [<00000000402d4608>] compat_SyS_clock_adjtime+0x40/0xc0 [<0000000040205024>] syscall_exit+0x0/0x14 This means the userspace program clock_adjtime called the clock_adjtime() syscall and then crashed inside the compat_get_timex() function. Syscalls should never crash programs, but instead return EFAULT. The IIR register contains the executed instruction, which disassebles into "ldw 0(sr3,r5),r9". This load-word instruction is part of __get_user() which tried to read the word at %r5/IOR (0xfa6f7fff). This means the unaligned handler jumped in. The unaligned handler is able to emulate all ldw instructions, but it fails if it fails to read the source e.g. because of page fault. The following program reproduces the problem: #define _GNU_SOURCE #include <unistd.h> #include <sys/syscall.h> #include <sys/mman.h> int main(void) { /* allocate 8k */ char *ptr = mmap(NULL, 2*4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); /* free second half (upper 4k) and make it invalid. */ munmap(ptr+4096, 4096); /* syscall where first int is unaligned and clobbers into invalid memory region */ /* syscall should return EFAULT */ return syscall(__NR_clock_adjtime, 0, ptr+4095); } To fix this issue we simply need to check if the faulting instruction address is in the exception fixup table when the unaligned handler failed. If it is, call the fixup routine instead of crashing. While looking at the unaligned handler I found another issue as well: The target register should not be modified if the handler was unsuccessful. Signed-off-by:
Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org Signed-off-by:
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Dave Weinstein authored
commit 7de24996 upstream. Add access checks to sys_oabi_epoll_wait() and sys_oabi_semtimedop(). This fixes CVE-2016-3857, a local privilege escalation under CONFIG_OABI_COMPAT. Cc: stable@vger.kernel.org Reported-by:
Chiachih Wu <wuchiachih@gmail.com> Reviewed-by:
Kees Cook <keescook@chromium.org> Reviewed-by:
Nicolas Pitre <nico@linaro.org> Signed-off-by:
Dave Weinstein <olorin@google.com> Signed-off-by:
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Russell King authored
commit e2dfb4b8 upstream. PTRACE_SETVFPREGS fails to properly mark the VFP register set to be reloaded, because it undoes one of the effects of vfp_flush_hwstate(). Specifically vfp_flush_hwstate() sets thread->vfpstate.hard.cpu to an invalid CPU number, but vfp_set() overwrites this with the original CPU number, thereby rendering the hardware state as apparently "valid", even though the software state is more recent. Fix this by reverting the previous change. Cc: <stable@vger.kernel.org> Fixes: 8130b9d7 ("ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers") Acked-by:
Will Deacon <will.deacon@arm.com> Tested-by:
Simon Marchi <simon.marchi@ericsson.com> Signed-off-by:
Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by:
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Paolo Bonzini authored
commit d14bdb55 upstream. MOV to DR6 or DR7 causes a #GP if an attempt is made to write a 1 to any of bits 63:32. However, this is not detected at KVM_SET_DEBUGREGS time, and the next KVM_RUN oopses: general protection fault: 0000 [#1] SMP CPU: 2 PID: 14987 Comm: a.out Not tainted 4.4.9-300.fc23.x86_64 #1 Hardware name: LENOVO 2325F51/2325F51, BIOS G2ET32WW (1.12 ) 05/30/2012 [...] Call Trace: [<ffffffffa072c93d>] kvm_arch_vcpu_ioctl_run+0x141d/0x14e0 [kvm] [<ffffffffa071405d>] kvm_vcpu_ioctl+0x33d/0x620 [kvm] [<ffffffff81241648>] do_vfs_ioctl+0x298/0x480 [<ffffffff812418a9>] SyS_ioctl+0x79/0x90 [<ffffffff817a0f2e>] entry_SYSCALL_64_fastpath+0x12/0x71 Code: 55 83 ff 07 48 89 e5 77 27 89 ff ff 24 fd 90 87 80 81 0f 23 fe 5d c3 0f 23 c6 5d c3 0f 23 ce 5d c3 0f 23 d6 5d c3 0f 23 de 5d c3 <0f> 23 f6 5d c3 0f 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 RIP [<ffffffff810639eb>] native_set_debugreg+0x2b/0x40 RSP <ffff88005836bd50> Testcase (beautified/reduced from syzkaller output): #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[8]; 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); memcpy(&dr, "\x5d\x6a\x6b\xe8\x57\x3b\x4b\x7e\xcf\x0d\xa1\x72" "\xa3\x4a\x29\x0c\xfc\x6d\x44\x00\xa7\x52\xc7\xd8" "\x00\xdb\x89\x9d\x78\xb5\x54\x6b\x6b\x13\x1c\xe9" "\x5e\xd3\x0e\x40\x6f\xb4\x66\xf7\x5b\xe3\x36\xcb", 48); r[7] = ioctl(r[4], KVM_SET_DEBUGREGS, &dr); r[6] = ioctl(r[4], KVM_RUN, 0); } Reported-by:
Dmitry Vyukov <dvyukov@google.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
Radim KrÄmáŠ<rkrcmar@redhat.com> Signed-off-by:
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Dave Chinner authored
commit 7d3aa7fe upstream. We don't write back stale inodes so we should skip them in xfs_iflush_cluster, too. cc: <stable@vger.kernel.org> # 3.10.x- Signed-off-by:
Dave Chinner <dchinner@redhat.com> Reviewed-by:
Brian Foster <bfoster@redhat.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Dave Chinner <david@fromorbit.com> Signed-off-by:
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Dave Chinner authored
commit 51b07f30 upstream. Some careless idiot(*) wrote crap code in commit 1a3e8f3d ("xfs: convert inode cache lookups to use RCU locking") back in late 2010, and so xfs_iflush_cluster checks the wrong inode for whether it is still valid under RCU protection. Fix it to lock and check the correct inode. (*) Careless-idiot: Dave Chinner <dchinner@redhat.com> cc: <stable@vger.kernel.org> # 3.10.x- Discovered-by:
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Dave Chinner authored
commit b1438f47 upstream. When a failure due to an inode buffer occurs, the error handling fails to abort the inode writeback correctly. This can result in the inode being reclaimed whilst still in the AIL, leading to use-after-free situations as well as filesystems that cannot be unmounted as the inode log items left in the AIL never get removed. Fix this by ensuring fatal errors from xfs_imap_to_bp() result in the inode flush being aborted correctly. Reported-by:
Shyam Kaushik <shyam@zadarastorage.com> Diagnosed-by:
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- 21 Aug, 2016 23 commits
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Ville Syrjälä authored
commit 3017cd63 upstream. With netconsole (at least) the pr_err("... disablingn") call can recurse back into the dma-debug code, where it'll try to grab free_entries_lock again. Avoid the problem by doing the printk after dropping the lock. Link: http://lkml.kernel.org/r/1463678421-18683-1-git-send-email-ville.syrjala@linux.intel.comSigned-off-by:
Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Vegard Nossum authored
commit 554a5ccc upstream. If we hit this error when mounted with errors=continue or errors=remount-ro: EXT4-fs error (device loop0): ext4_mb_mark_diskspace_used:2940: comm ext4.exe: Allocating blocks 5090-6081 which overlap fs metadata then ext4_mb_new_blocks() will call ext4_mb_release_context() and try to continue. However, ext4_mb_release_context() is the wrong thing to call here since we are still actually using the allocation context. Instead, just error out. We could retry the allocation, but there is a possibility of getting stuck in an infinite loop instead, so this seems safer. [ Fixed up so we don't return EAGAIN to userspace. --tytso ] Fixes: 8556e8f3 ("ext4: Don't allow new groups to be added during block allocation") Signed-off-by:
Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by:
Theodore Ts'o <tytso@mit.edu> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: stable@vger.kernel.org [wt: 3.10 doesn't have EFSCORRUPTED, but XFS uses EUCLEAN as does 3.14 on this patch so use this instead] Signed-off-by:
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Vegard Nossum authored
commit c65d5c6c upstream. If we encounter a filesystem error during orphan cleanup, we should stop. Otherwise, we may end up in an infinite loop where the same inode is processed again and again. EXT4-fs (loop0): warning: checktime reached, running e2fsck is recommended EXT4-fs error (device loop0): ext4_mb_generate_buddy:758: group 2, block bitmap and bg descriptor inconsistent: 6117 vs 0 free clusters Aborting journal on device loop0-8. EXT4-fs (loop0): Remounting filesystem read-only EXT4-fs error (device loop0) in ext4_free_blocks:4895: Journal has aborted EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted EXT4-fs error (device loop0) in ext4_ext_remove_space:3068: IO failure EXT4-fs error (device loop0) in ext4_ext_truncate:4667: Journal has aborted EXT4-fs error (device loop0) in ext4_orphan_del:2927: Journal has aborted EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted EXT4-fs (loop0): Inode 16 (00000000618192a0): orphan list check failed! [...] EXT4-fs (loop0): Inode 16 (0000000061819748): orphan list check failed! [...] EXT4-fs (loop0): Inode 16 (0000000061819bf0): orphan list check failed! [...] See-also: c9eb13a9 ("ext4: fix hang when processing corrupted orphaned inode list") Cc: Jan Kara <jack@suse.cz> Signed-off-by:
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Vegard Nossum authored
commit 6a7fd522 upstream. If ext4_fill_super() fails early, it's possible for ext4_evict_inode() to call ext4_should_journal_data() before superblock options and flags are fully set up. In that case, the iput() on the journal inode can end up causing a BUG(). Work around this problem by reordering the tests so we only call ext4_should_journal_data() after we know it's not the journal inode. Fixes: 2d859db3 ("ext4: fix data corruption in inodes with journalled data") Fixes: 2b405bfa ("ext4: fix data=journal fast mount/umount hang") Cc: Jan Kara <jack@suse.cz> Cc: stable@vger.kernel.org Signed-off-by:
Jan Kara <jack@suse.cz> Signed-off-by:
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Vegard Nossum authored
commit f70749ca upstream. An extent with lblock = 4294967295 and len = 1 will pass the ext4_valid_extent() test: ext4_lblk_t last = lblock + len - 1; if (len == 0 || lblock > last) return 0; since last = 4294967295 + 1 - 1 = 4294967295. This would later trigger the BUG_ON(es->es_lblk + es->es_len < es->es_lblk) in ext4_es_end(). We can simplify it by removing the - 1 altogether and changing the test to use lblock + len <= lblock, since now if len = 0, then lblock + 0 == lblock and it fails, and if len > 0 then lblock + len > lblock in order to pass (i.e. it doesn't overflow). Fixes: 5946d089 ("ext4: check for overlapping extents in ext4_valid_extent_entries()") Fixes: 2f974865 ("ext4: check for zero length extent explicitly") Cc: Eryu Guan <guaneryu@gmail.com> Cc: stable@vger.kernel.org Signed-off-by:
Phil Turnbull <phil.turnbull@oracle.com> Signed-off-by:
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Vegard Nossum authored
commit 7bc94916 upstream. Although the extent tree depth of 5 should enough be for the worst case of 2*32 extents of length 1, the extent tree code does not currently to merge nodes which are less than half-full with a sibling node, or to shrink the tree depth if possible. So it's possible, at least in theory, for the tree depth to be greater than 5. However, even in the worst case, a tree depth of 32 is highly unlikely, and if the file system is maliciously corrupted, an insanely large eh_depth can cause memory allocation failures that will trigger kernel warnings (here, eh_depth = 65280): JBD2: ext4.exe wants too many credits credits:195849 rsv_credits:0 max:256 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 50 at fs/jbd2/transaction.c:293 start_this_handle+0x569/0x580 CPU: 0 PID: 50 Comm: ext4.exe Not tainted 4.7.0-rc5+ #508 Stack: 604a8947 625badd8 0002fd09 00000000 60078643 00000000 62623910 601bf9bc 62623970 6002fc84 626239b0 900000125 Call Trace: [<6001c2dc>] show_stack+0xdc/0x1a0 [<601bf9bc>] dump_stack+0x2a/0x2e [<6002fc84>] __warn+0x114/0x140 [<6002fdff>] warn_slowpath_null+0x1f/0x30 [<60165829>] start_this_handle+0x569/0x580 [<60165d4e>] jbd2__journal_start+0x11e/0x220 [<60146690>] __ext4_journal_start_sb+0x60/0xa0 [<60120a81>] ext4_truncate+0x131/0x3a0 [<60123677>] ext4_setattr+0x757/0x840 [<600d5d0f>] notify_change+0x16f/0x2a0 [<600b2b16>] do_truncate+0x76/0xc0 [<600c3e56>] path_openat+0x806/0x1300 [<600c55c9>] do_filp_open+0x89/0xf0 [<600b4074>] do_sys_open+0x134/0x1e0 [<600b4140>] SyS_open+0x20/0x30 [<6001ea68>] handle_syscall+0x88/0x90 [<600295fd>] userspace+0x3fd/0x500 [<6001ac55>] fork_handler+0x85/0x90 ---[ end trace 08b0b88b6387a244 ]--- [ Commit message modified and the extent tree depath check changed from 5 to 32 -- tytso ] Cc: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by:
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Nicolai Stange authored
commit 935244cd upstream. Currently, in ext4_mb_init(), there's a loop like the following: do { ... offset += 1 << (sb->s_blocksize_bits - i); i++; } while (i <= sb->s_blocksize_bits + 1); Note that the updated offset is used in the loop's next iteration only. However, at the last iteration, that is at i == sb->s_blocksize_bits + 1, the shift count becomes equal to (unsigned)-1 > 31 (c.f. C99 6.5.7(3)) and UBSAN reports UBSAN: Undefined behaviour in fs/ext4/mballoc.c:2621:15 shift exponent 4294967295 is too large for 32-bit type 'int' [...] Call Trace: [<ffffffff818c4d25>] dump_stack+0xbc/0x117 [<ffffffff818c4c69>] ? _atomic_dec_and_lock+0x169/0x169 [<ffffffff819411ab>] ubsan_epilogue+0xd/0x4e [<ffffffff81941cac>] __ubsan_handle_shift_out_of_bounds+0x1fb/0x254 [<ffffffff81941ab1>] ? __ubsan_handle_load_invalid_value+0x158/0x158 [<ffffffff814b6dc1>] ? kmem_cache_alloc+0x101/0x390 [<ffffffff816fc13b>] ? ext4_mb_init+0x13b/0xfd0 [<ffffffff814293c7>] ? create_cache+0x57/0x1f0 [<ffffffff8142948a>] ? create_cache+0x11a/0x1f0 [<ffffffff821c2168>] ? mutex_lock+0x38/0x60 [<ffffffff821c23ab>] ? mutex_unlock+0x1b/0x50 [<ffffffff814c26ab>] ? put_online_mems+0x5b/0xc0 [<ffffffff81429677>] ? kmem_cache_create+0x117/0x2c0 [<ffffffff816fcc49>] ext4_mb_init+0xc49/0xfd0 [...] Observe that the mentioned shift exponent, 4294967295, equals (unsigned)-1. Unless compilers start to do some fancy transformations (which at least GCC 6.0.0 doesn't currently do), the issue is of cosmetic nature only: the such calculated value of offset is never used again. Silence UBSAN by introducing another variable, offset_incr, holding the next increment to apply to offset and adjust that one by right shifting it by one position per loop iteration. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=114701 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112161 Cc: stable@vger.kernel.org Signed-off-by:
Nicolai Stange <nicstange@gmail.com> Signed-off-by:
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Nicolai Stange authored
commit b5cb316c upstream. Currently, in mb_find_order_for_block(), there's a loop like the following: while (order <= e4b->bd_blkbits + 1) { ... bb += 1 << (e4b->bd_blkbits - order); } Note that the updated bb is used in the loop's next iteration only. However, at the last iteration, that is at order == e4b->bd_blkbits + 1, the shift count becomes negative (c.f. C99 6.5.7(3)) and UBSAN reports UBSAN: Undefined behaviour in fs/ext4/mballoc.c:1281:11 shift exponent -1 is negative [...] Call Trace: [<ffffffff818c4d35>] dump_stack+0xbc/0x117 [<ffffffff818c4c79>] ? _atomic_dec_and_lock+0x169/0x169 [<ffffffff819411bb>] ubsan_epilogue+0xd/0x4e [<ffffffff81941cbc>] __ubsan_handle_shift_out_of_bounds+0x1fb/0x254 [<ffffffff81941ac1>] ? __ubsan_handle_load_invalid_value+0x158/0x158 [<ffffffff816e93a0>] ? ext4_mb_generate_from_pa+0x590/0x590 [<ffffffff816502c8>] ? ext4_read_block_bitmap_nowait+0x598/0xe80 [<ffffffff816e7b7e>] mb_find_order_for_block+0x1ce/0x240 [...] Unless compilers start to do some fancy transformations (which at least GCC 6.0.0 doesn't currently do), the issue is of cosmetic nature only: the such calculated value of bb is never used again. Silence UBSAN by introducing another variable, bb_incr, holding the next increment to apply to bb and adjust that one by right shifting it by one position per loop iteration. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=114701 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112161 Cc: stable@vger.kernel.org Signed-off-by:
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Theodore Ts'o authored
commit c9eb13a9 upstream. If the orphaned inode list contains inode #5, ext4_iget() returns a bad inode (since the bootloader inode should never be referenced directly). Because of the bad inode, we end up processing the inode repeatedly and this hangs the machine. This can be reproduced via: mke2fs -t ext4 /tmp/foo.img 100 debugfs -w -R "ssv last_orphan 5" /tmp/foo.img mount -o loop /tmp/foo.img /mnt (But don't do this if you are using an unpatched kernel if you care about the system staying functional. :-) This bug was found by the port of American Fuzzy Lop into the kernel to find file system problems[1]. (Since it *only* happens if inode #5 shows up on the orphan list --- 3, 7, 8, etc. won't do it, it's not surprising that AFL needed two hours before it found it.) [1] http://events.linuxfoundation.org/sites/events/files/slides/AFL%20filesystem%20fuzzing%2C%20Vault%202016_0.pdf Cc: stable@vger.kernel.org Reported by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by:
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Alex Deucher authored
commit 3edc38a0 upstream. Some of the checks didn't handle frev 2 tables properly. Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Signed-off-by:
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Lyude authored
commit 14ff8d48 upstream. DRM_CONNECTOR_POLL_CONNECT only enables polling for connections, not disconnections. Because of this, we end up losing hotplug polling for analog connectors once they get connected. Easy way to reproduce: - Grab a machine with a radeon GPU and a VGA port - Plug a monitor into the VGA port, wait for it to update the connector from disconnected to connected - Disconnect the monitor on VGA, a hotplug event is never sent for the removal of the connector. Originally, only using DRM_CONNECTOR_POLL_CONNECT might have been a good idea since doing VGA polling can sometimes result in having to mess with the DAC voltages to figure out whether or not there's actually something there since VGA doesn't have HPD. Doing this would have the potential of showing visible artifacts on the screen every time we ran a poll while a VGA display was connected. Luckily, radeon_vga_detect() only resorts to this sort of polling if the poll is forced, and DRM's polling helper doesn't force it's polls. Additionally, this removes some assignments to connector->polled that weren't actually doing anything. Cc: stable@vger.kernel.org Signed-off-by:
Lyude <cpaul@redhat.com> Signed-off-by:
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Alex Deucher authored
commit d814b24f upstream. ATPX dGPU power control requires a 200ms delay between power off and on. This should fix dGPU failures on resume from power off. Reviewed-by:
Hawking Zhang <Hawking.Zhang@amd.com> Acked-by:
Christian König <christian.koenig@amd.com> Signed-off-by:
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Alex Deucher authored
commit 05082b8b upstream. When executing in a PCI passthrough based virtuzliation environment, the hypervisor will usually attempt to send a PCIe bus reset signal to the ASIC when the VM reboots. In this scenario, the card is not correctly initialized, but we still consider it to be posted. Therefore, in a passthrough based environemnt we should always post the card to guarantee it is in a good state for driver initialization. Ported from amdgpu commit: amdgpu: fix asic initialization for virtualized environments Cc: Andres Rodriguez <andres.rodriguez@amd.com> Cc: Alex Williamson <alex.williamson@redhat.com> Signed-off-by:
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Lyude authored
commit 255f0e7c upstream. During boot, MST hotplugs are generally expected (even if no physical hotplugging occurs) and result in DRM's connector topology changing. This means that using num_connector from the current mode configuration can lead to the number of connectors changing under us. This can lead to some nasty scenarios in fbcon: - We allocate an array to the size of dev->mode_config.num_connectors. - MST hotplug occurs, dev->mode_config.num_connectors gets incremented. - We try to loop through each element in the array using the new value of dev->mode_config.num_connectors, and end up going out of bounds since dev->mode_config.num_connectors is now larger then the array we allocated. fb_helper->connector_count however, will always remain consistent while we do a modeset in fb_helper. Note: This is just polish for 4.7, Dave Airlie's drm_connector refcounting fixed these bugs for real. But it's good enough duct-tape for stable kernel backporting, since backporting the refcounting changes is way too invasive. Signed-off-by:
Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1463065021-18280-3-git-send-email-cpaul@redhat.comSigned-off-by:
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Itai Handler authored
commit 7ccca1d5 upstream. Fix possible out of bounds read, by adding missing comma. The code may read pass the end of the dsi_errors array when the most significant bit (bit #31) in the intr_stat register is set. This bug has been detected using CppCheck (static analysis tool). Cc: stable@vger.kernel.org Signed-off-by:
Itai Handler <itai_handler@hotmail.com> Signed-off-by:
Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Signed-off-by:
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Tomáš Trnka authored
commit c0cb8bf3 upstream. The length of the GSS MIC token need not be a multiple of four bytes. It is then padded by XDR to a multiple of 4 B, but unwrap_integ_data() would previously only trim mic.len + 4 B. The remaining up to three bytes would then trigger a check in nfs4svc_decode_compoundargs(), leading to a "garbage args" error and mount failure: nfs4svc_decode_compoundargs: compound not properly padded! nfsd: failed to decode arguments! This would prevent older clients using the pre-RFC 4121 MIC format (37-byte MIC including a 9-byte OID) from mounting exports from v3.9+ servers using krb5i. The trimming was introduced by commit 4c190e2f ("sunrpc: trim off trailing checksum before returning decrypted or integrity authenticated buffer"). Fixes: 4c190e2f "unrpc: trim off trailing checksum..." Signed-off-by:
Tomáš Trnka <ttrnka@mail.muni.cz> Cc: stable@vger.kernel.org Acked-by:
Jeff Layton <jlayton@poochiereds.net> Signed-off-by:
J. Bruce Fields <bfields@redhat.com> Signed-off-by:
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Cyril Bur authored
commit 8e96a87c upstream. Userspace can quite legitimately perform an exec() syscall with a suspended transaction. exec() does not return to the old process, rather it load a new one and starts that, the expectation therefore is that the new process starts not in a transaction. Currently exec() is not treated any differently to any other syscall which creates problems. Firstly it could allow a new process to start with a suspended transaction for a binary that no longer exists. This means that the checkpointed state won't be valid and if the suspended transaction were ever to be resumed and subsequently aborted (a possibility which is exceedingly likely as exec()ing will likely doom the transaction) the new process will jump to invalid state. Secondly the incorrect attempt to keep the transactional state while still zeroing state for the new process creates at least two TM Bad Things. The first triggers on the rfid to return to userspace as start_thread() has given the new process a 'clean' MSR but the suspend will still be set in the hardware MSR. The second TM Bad Thing triggers in __switch_to() as the processor is still transactionally suspended but __switch_to() wants to zero the TM sprs for the new process. This is an example of the outcome of calling exec() with a suspended transaction. Note the first 700 is likely the first TM bad thing decsribed earlier only the kernel can't report it as we've loaded userspace registers. c000000000009980 is the rfid in fast_exception_return() Bad kernel stack pointer 3fffcfa1a370 at c000000000009980 Oops: Bad kernel stack pointer, sig: 6 [#1] CPU: 0 PID: 2006 Comm: tm-execed Not tainted NIP: c000000000009980 LR: 0000000000000000 CTR: 0000000000000000 REGS: c00000003ffefd40 TRAP: 0700 Not tainted MSR: 8000000300201031 <SF,ME,IR,DR,LE,TM[SE]> CR: 00000000 XER: 00000000 CFAR: c0000000000098b4 SOFTE: 0 PACATMSCRATCH: b00000010000d033 GPR00: 0000000000000000 00003fffcfa1a370 0000000000000000 0000000000000000 GPR04: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR12: 00003fff966611c0 0000000000000000 0000000000000000 0000000000000000 NIP [c000000000009980] fast_exception_return+0xb0/0xb8 LR [0000000000000000] (null) Call Trace: Instruction dump: f84d0278 e9a100d8 7c7b03a6 e84101a0 7c4ff120 e8410170 7c5a03a6 e8010070 e8410080 e8610088 e8810090 e8210078 <4c000024> 48000000 e8610178 88ed023b Kernel BUG at c000000000043e80 [verbose debug info unavailable] Unexpected TM Bad Thing exception at c000000000043e80 (msr 0x201033) Oops: Unrecoverable exception, sig: 6 [#2] CPU: 0 PID: 2006 Comm: tm-execed Tainted: G D task: c0000000fbea6d80 ti: c00000003ffec000 task.ti: c0000000fb7ec000 NIP: c000000000043e80 LR: c000000000015a24 CTR: 0000000000000000 REGS: c00000003ffef7e0 TRAP: 0700 Tainted: G D MSR: 8000000300201033 <SF,ME,IR,DR,RI,LE,TM[SE]> CR: 28002828 XER: 00000000 CFAR: c000000000015a20 SOFTE: 0 PACATMSCRATCH: b00000010000d033 GPR00: 0000000000000000 c00000003ffefa60 c000000000db5500 c0000000fbead000 GPR04: 8000000300001033 2222222222222222 2222222222222222 00000000ff160000 GPR08: 0000000000000000 800000010000d033 c0000000fb7e3ea0 c00000000fe00004 GPR12: 0000000000002200 c00000000fe00000 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 c0000000fbea7410 00000000ff160000 GPR24: c0000000ffe1f600 c0000000fbea8700 c0000000fbea8700 c0000000fbead000 GPR28: c000000000e20198 c0000000fbea6d80 c0000000fbeab680 c0000000fbea6d80 NIP [c000000000043e80] tm_restore_sprs+0xc/0x1c LR [c000000000015a24] __switch_to+0x1f4/0x420 Call Trace: Instruction dump: 7c800164 4e800020 7c0022a6 f80304a8 7c0222a6 f80304b0 7c0122a6 f80304b8 4e800020 e80304a8 7c0023a6 e80304b0 <7c0223a6> e80304b8 7c0123a6 4e800020 This fixes CVE-2016-5828. Fixes: bc2a9408 ("powerpc: Hook in new transactional memory code") Cc: stable@vger.kernel.org # v3.9+ Signed-off-by:
Cyril Bur <cyrilbur@gmail.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Gavin Shan authored
commit 8a934efe upstream. In commit 8445a87f "powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism", the PE address was replaced with the PCI config address in order to remove dependency on EEH. According to PAPR spec, firmware (pHyp or QEMU) should accept "xxBBSSxx" format PCI config address, not "xxxxBBSS" provided by the patch. Note that "BB" is PCI bus number and "SS" is the combination of slot and function number. This fixes the PCI address passed to DDW RTAS calls. Fixes: 8445a87f ("powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism") Cc: stable@vger.kernel.org # v3.4+ Reported-by:
Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Signed-off-by:
Gavin Shan <gwshan@linux.vnet.ibm.com> Tested-by:
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Guilherme G. Piccoli authored
commit 8445a87f upstream. Commit 39baadbf ("powerpc/eeh: Remove eeh information from pci_dn") changed the pci_dn struct by removing its EEH-related members. As part of this clean-up, DDW mechanism was modified to read the device configuration address from eeh_dev struct. As a consequence, now if we disable EEH mechanism on kernel command-line for example, the DDW mechanism will fail, generating a kernel oops by dereferencing a NULL pointer (which turns to be the eeh_dev pointer). This patch just changes the configuration address calculation on DDW functions to a manual calculation based on pci_dn members instead of using eeh_dev-based address. No functional changes were made. This was tested on pSeries, both in PHyp and qemu guest. Fixes: 39baadbf ("powerpc/eeh: Remove eeh information from pci_dn") Cc: stable@vger.kernel.org # v3.4+ Reviewed-by:
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Russell Currey authored
commit 871e178e upstream. In the "ibm,configure-pe" and "ibm,configure-bridge" RTAS calls, the spec states that values of 9900-9905 can be returned, indicating that software should delay for 10^x (where x is the last digit, i.e. 990x) milliseconds and attempt the call again. Currently, the kernel doesn't know about this, and respecting it fixes some PCI failures when the hypervisor is busy. The delay is capped at 0.2 seconds. Cc: <stable@vger.kernel.org> # 3.10+ Signed-off-by:
Russell Currey <ruscur@russell.cc> Acked-by:
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Thomas Huth authored
commit 8dd75ccb upstream. We are already using the privileged versions of MMCR0, MMCR1 and MMCRA in the kernel, so for MMCR2, we should better use the privileged versions, too, to be consistent. Fixes: 240686c1 ("powerpc: Initialise PMU related regs on Power8") Suggested-by:
Paul Mackerras <paulus@ozlabs.org> Signed-off-by:
Thomas Huth <thuth@redhat.com> Acked-by:
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Thomas Huth authored
commit d23fac2b upstream. The SIAR and SDAR registers are available twice, one time as SPRs 780 / 781 (unprivileged, but read-only), and one time as the SPRs 796 / 797 (privileged, but read and write). The Linux kernel code currently uses the unprivileged SPRs - while this is OK for reading, writing to that register of course does not work. Since the KVM code tries to write to this register, too (see the mtspr in book3s_hv_rmhandlers.S), the contents of this register sometimes get lost for the guests, e.g. during migration of a VM. To fix this issue, simply switch to the privileged SPR numbers instead. Signed-off-by:
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Hari Bathini authored
commit 8ed8ab40 upstream. Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long (8 instructions), which is not enough for the full first-level interrupt handler. For these we need to branch to an out-of-line (OOL) handler. But when we are running a relocatable kernel, interrupt vectors till __end_interrupts marker are copied down to real address 0x100. So, branching to labels (ie. OOL handlers) outside this section must be handled differently (see LOAD_HANDLER()), considering relocatable kernel, which would need at least 4 instructions. However, branching from interrupt vector means that we corrupt the CFAR (come-from address register) on POWER7 and later processors as mentioned in commit 1707dd16. So, EXCEPTION_PROLOG_0 (6 instructions) that contains the part up to the point where the CFAR is saved in the PACA should be part of the short interrupt vectors before we branch out to OOL handlers. But as mentioned already, there are interrupt vectors on 64-bit POWER server processors that are only 32 bytes long (like vectors 0x4f00, 0x4f20, etc.), which cannot accomodate the above two cases at the same time owing to space constraint. Currently, in these interrupt vectors, we simply branch out to OOL handlers, without using LOAD_HANDLER(), which leaves us vulnerable when running a relocatable kernel (eg. kdump case). While this has been the case for sometime now and kdump is used widely, we were fortunate not to see any problems so far, for three reasons: 1. In almost all cases, production kernel (relocatable) is used for kdump as well, which would mean that crashed kernel's OOL handler would be at the same place where we end up branching to, from short interrupt vector of kdump kernel. 2. Also, OOL handler was unlikely the reason for crash in almost all the kdump scenarios, which meant we had a sane OOL handler from crashed kernel that we branched to. 3. On most 64-bit POWER server processors, page size is large enough that marking interrupt vector code as executable (see commit 429d2e83) leads to marking OOL handler code from crashed kernel, that sits right below interrupt vector code from kdump kernel, as executable as well. Let us fix this by moving the __end_interrupts marker down past OOL handlers to make sure that we also copy OOL handlers to real address 0x100 when running a relocatable kernel. This fix has been tested successfully in kdump scenario, on an LPAR with 4K page size by using different default/production kernel and kdump kernel. Also tested by manually corrupting the OOL handlers in the first kernel and then kdump'ing, and then causing the OOL handlers to fire - mpe. Fixes: c1fb6816 ("powerpc: Add relocation on exception vector handlers") Signed-off-by:
Hari Bathini <hbathini@linux.vnet.ibm.com> Signed-off-by:
Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by:
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