user/sven/linux.git/kernel, branch v5.14.9

bpf: Add oversize check before call kvcalloc()

2021-09-30T08:13:04Z

[ Upstream commit 0e6491b559704da720f6da09dd0a52c4df44c514 ] Commit 7661809d493b ("mm: don't allow oversized kvmalloc() calls") add the oversize check. When the allocation is larger than what kmalloc() supports, the following warning triggered: WARNING: CPU: 0 PID: 8408 at mm/util.c:597 kvmalloc_node+0x108/0x110 mm/util.c:597 Modules linked in: CPU: 0 PID: 8408 Comm: syz-executor221 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:kvmalloc_node+0x108/0x110 mm/util.c:597 Call Trace: kvmalloc include/linux/mm.h:806 [inline] kvmalloc_array include/linux/mm.h:824 [inline] kvcalloc include/linux/mm.h:829 [inline] check_btf_line kernel/bpf/verifier.c:9925 [inline] check_btf_info kernel/bpf/verifier.c:10049 [inline] bpf_check+0xd634/0x150d0 kernel/bpf/verifier.c:13759 bpf_prog_load kernel/bpf/syscall.c:2301 [inline] __sys_bpf+0x11181/0x126e0 kernel/bpf/syscall.c:4587 __do_sys_bpf kernel/bpf/syscall.c:4691 [inline] __se_sys_bpf kernel/bpf/syscall.c:4689 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4689 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported-by: syzbot+f3e749d4c662818ae439@syzkaller.appspotmail.com Signed-off-by: Bixuan Cui Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20210911005557.45518-1-cuibixuan@huawei.com Signed-off-by: Sasha Levin

dma-debug: prevent an error message from causing runtime problems

2021-09-30T08:13:04Z

[ Upstream commit 510e1a724ab1bf38150be2c1acabb303f98d0047 ] For some drivers, that use the DMA API. This error message can be reached several millions of times per second, causing spam to the kernel's printk buffer and bringing the CPU usage up to 100% (so, it should be rate limited). However, since there is at least one driver that is in the mainline and suffers from the error condition, it is more useful to err_printk() here instead of just rate limiting the error message (in hopes that it will make it easier for other drivers that suffer from this issue to be spotted). Link: https://lkml.kernel.org/r/fd67fbac-64bf-f0ea-01e1-5938ccfab9d0@arm.com Reported-by: Jeremy Linton Signed-off-by: Hamza Mahfooz Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin

blktrace: Fix uaf in blk_trace access after removing by sysfs

2021-09-30T08:13:03Z

[ Upstream commit 5afedf670caf30a2b5a52da96eb7eac7dee6a9c9 ] There is an use-after-free problem triggered by following process: P1(sda) P2(sdb) echo 0 > /sys/block/sdb/trace/enable blk_trace_remove_queue synchronize_rcu blk_trace_free relay_close rcu_read_lock __blk_add_trace trace_note_tsk (Iterate running_trace_list) relay_close_buf relay_destroy_buf kfree(buf) trace_note(sdb's bt) relay_reserve buf->offset <- nullptr deference (use-after-free) !!! rcu_read_unlock [ 502.714379] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 502.715260] #PF: supervisor read access in kernel mode [ 502.715903] #PF: error_code(0x0000) - not-present page [ 502.716546] PGD 103984067 P4D 103984067 PUD 17592b067 PMD 0 [ 502.717252] Oops: 0000 [#1] SMP [ 502.720308] RIP: 0010:trace_note.isra.0+0x86/0x360 [ 502.732872] Call Trace: [ 502.733193] __blk_add_trace.cold+0x137/0x1a3 [ 502.733734] blk_add_trace_rq+0x7b/0xd0 [ 502.734207] blk_add_trace_rq_issue+0x54/0xa0 [ 502.734755] blk_mq_start_request+0xde/0x1b0 [ 502.735287] scsi_queue_rq+0x528/0x1140 ... [ 502.742704] sg_new_write.isra.0+0x16e/0x3e0 [ 502.747501] sg_ioctl+0x466/0x1100 Reproduce method: ioctl(/dev/sda, BLKTRACESETUP, blk_user_trace_setup[buf_size=127]) ioctl(/dev/sda, BLKTRACESTART) ioctl(/dev/sdb, BLKTRACESETUP, blk_user_trace_setup[buf_size=127]) ioctl(/dev/sdb, BLKTRACESTART) echo 0 > /sys/block/sdb/trace/enable & // Add delay(mdelay/msleep) before kernel enters blk_trace_free() ioctl$SG_IO(/dev/sda, SG_IO, ...) // Enters trace_note_tsk() after blk_trace_free() returned // Use mdelay in rcu region rather than msleep(which may schedule out) Remove blk_trace from running_list before calling blk_trace_free() by sysfs if blk_trace is at Blktrace_running state. Fixes: c71a896154119f ("blktrace: add ftrace plugin") Signed-off-by: Zhihao Cheng Link: https://lore.kernel.org/r/20210923134921.109194-1-chengzhihao1@huawei.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

KVM: rseq: Update rseq when processing NOTIFY_RESUME on xfer to KVM guest

2021-09-30T08:12:55Z

commit 8646e53633f314e4d746a988240d3b951a92f94a upstream. Invoke rseq's NOTIFY_RESUME handler when processing the flag prior to transferring to a KVM guest, which is roughly equivalent to an exit to userspace and processes many of the same pending actions. While the task cannot be in an rseq critical section as the KVM path is reachable only by via ioctl(KVM_RUN), the side effects that apply to rseq outside of a critical section still apply, e.g. the current CPU needs to be updated if the task is migrated. Clearing TIF_NOTIFY_RESUME without informing rseq can lead to segfaults and other badness in userspace VMMs that use rseq in combination with KVM, e.g. due to the CPU ID being stale after task migration. Fixes: 72c3c0fe54a3 ("x86/kvm: Use generic xfer to guest work function") Reported-by: Peter Foley Bisected-by: Doug Evans Acked-by: Mathieu Desnoyers Cc: Shakeel Butt Cc: Thomas Gleixner Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Message-Id: <20210901203030.1292304-2-seanjc@google.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

sched/idle: Make the idle timer expire in hard interrupt context

2021-09-26T12:10:25Z

[ Upstream commit 9848417926353daa59d2b05eb26e185063dbac6e ] The intel powerclamp driver will setup a per-CPU worker with RT priority. The worker will then invoke play_idle() in which it remains in the idle poll loop until it is stopped by the timer it started earlier. That timer needs to expire in hard interrupt context on PREEMPT_RT. Otherwise the timer will expire in ksoftirqd as a SOFT timer but that task won't be scheduled on the CPU because its priority is lower than the priority of the worker which is in the idle loop. Always expire the idle timer in hard interrupt context. Reported-by: Thomas Gleixner Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20210906113034.jgfxrjdvxnjqgtmc@linutronix.de Signed-off-by: Sasha Levin

tracing/boot: Fix to loop on only subkeys

2021-09-26T12:10:19Z

[ Upstream commit cfd799837dbc48499abb05d1891b3d9992354d3a ] Since the commit e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key") allows to co-exist a value node and key nodes under a node, xbc_node_for_each_child() is not only returning key node but also a value node. In the boot-time tracing using xbc_node_for_each_child() to iterate the events, groups and instances, but those must be key nodes. Thus it must use xbc_node_for_each_subkey(). Link: https://lkml.kernel.org/r/163112988361.74896.2267026262061819145.stgit@devnote2 Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key") Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sasha Levin

profiling: fix shift-out-of-bounds bugs

2021-09-26T12:10:17Z

commit 2d186afd04d669fe9c48b994c41a7405a3c9f16d upstream. Syzbot reported shift-out-of-bounds bug in profile_init(). The problem was in incorrect prof_shift. Since prof_shift value comes from userspace we need to clamp this value into [0, BITS_PER_LONG -1] boundaries. Second possible shiht-out-of-bounds was found by Tetsuo: sample_step local variable in read_profile() had "unsigned int" type, but prof_shift allows to make a BITS_PER_LONG shift. So, to prevent possible shiht-out-of-bounds sample_step type was changed to "unsigned long". Also, "unsigned short int" will be sufficient for storing [0, BITS_PER_LONG] value, that's why there is no need for "unsigned long" prof_shift. Link: https://lkml.kernel.org/r/20210813140022.5011-1-paskripkin@gmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-and-tested-by: syzbot+e68c89a9510c159d9684@syzkaller.appspotmail.com Suggested-by: Tetsuo Handa Signed-off-by: Pavel Skripkin Cc: Thomas Gleixner Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

prctl: allow to setup brk for et_dyn executables

2021-09-26T12:10:17Z

commit e1fbbd073137a9d63279f6bf363151a938347640 upstream. Keno Fischer reported that when a binray loaded via ld-linux-x the prctl(PR_SET_MM_MAP) doesn't allow to setup brk value because it lays before mm:end_data. For example a test program shows | # ~/t | | start_code 401000 | end_code 401a15 | start_stack 7ffce4577dd0 | start_data 403e10 | end_data 40408c | start_brk b5b000 | sbrk(0) b5b000 and when executed via ld-linux | # /lib64/ld-linux-x86-64.so.2 ~/t | | start_code 7fc25b0a4000 | end_code 7fc25b0c4524 | start_stack 7fffcc6b2400 | start_data 7fc25b0ce4c0 | end_data 7fc25b0cff98 | start_brk 55555710c000 | sbrk(0) 55555710c000 This of course prevent criu from restoring such programs. Looking into how kernel operates with brk/start_brk inside brk() syscall I don't see any problem if we allow to setup brk/start_brk without checking for end_data. Even if someone pass some weird address here on a purpose then the worst possible result will be an unexpected unmapping of existing vma (own vma, since prctl works with the callers memory) but test for RLIMIT_DATA is still valid and a user won't be able to gain more memory in case of expanding VMAs via new values shipped with prctl call. Link: https://lkml.kernel.org/r/20210121221207.GB2174@grain Fixes: bbdc6076d2e5 ("binfmt_elf: move brk out of mmap when doing direct loader exec") Signed-off-by: Cyrill Gorcunov Reported-by: Keno Fischer Acked-by: Andrey Vagin Tested-by: Andrey Vagin Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Kirill Tkhai Cc: Eric W. Biederman Cc: Pavel Tikhomirov Cc: Alexander Mikhalitsyn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

tracing/boot: Fix a hist trigger dependency for boot time tracing

2021-09-22T10:39:29Z

[ Upstream commit 6fe7c745f2acb73e4cc961d7f91125eef5a8861f ] Fixes a build error when CONFIG_HIST_TRIGGERS=n with boot-time tracing. Since the trigger_process_regex() is defined only when CONFIG_HIST_TRIGGERS=y, if it is disabled, the 'actions' event option also must be disabled. Link: https://lkml.kernel.org/r/162856123376.203126.582144262622247352.stgit@devnote2 Fixes: 81a59555ff15 ("tracing/boot: Add per-event settings") Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sasha Levin

tracing/probes: Reject events which have the same name of existing one

2021-09-22T10:39:26Z

[ Upstream commit 8e242060c6a4947e8ae7d29794af6a581db08841 ] Since kprobe_events and uprobe_events only check whether the other same-type probe event has the same name or not, if the user gives the same name of the existing tracepoint event (or the other type of probe events), it silently fails to create the tracefs entry (but registered.) as below. /sys/kernel/tracing # ls events/task/task_rename enable filter format hist id trigger /sys/kernel/tracing # echo p:task/task_rename vfs_read >> kprobe_events [ 113.048508] Could not create tracefs 'task_rename' directory /sys/kernel/tracing # cat kprobe_events p:task/task_rename vfs_read To fix this issue, check whether the existing events have the same name or not in trace_probe_register_event_call(). If exists, it rejects to register the new event. Link: https://lkml.kernel.org/r/162936876189.187130.17558311387542061930.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sasha Levin