kernel/linux.git, branch v4.14.227

Linux 4.14.227

2021-03-24T10:05:06+00:00

Tested-by: Jon Hunter Tested-by: Guenter Roeck Tested-by: Jason Self Tested-by: Linux Kernel Functional Testing Tested-by: Hulk Robot Link: https://lore.kernel.org/r/20210322121920.053255560@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

genirq: Disable interrupts for force threaded handlers

2021-03-24T10:05:06+00:00

commit 81e2073c175b887398e5bca6c004efa89983f58d upstream. With interrupt force threading all device interrupt handlers are invoked from kernel threads. Contrary to hard interrupt context the invocation only disables bottom halfs, but not interrupts. This was an oversight back then because any code like this will have an issue: thread(irq_A) irq_handler(A) spin_lock(&foo->lock); interrupt(irq_B) irq_handler(B) spin_lock(&foo->lock); This has been triggered with networking (NAPI vs. hrtimers) and console drivers where printk() happens from an interrupt which interrupted the force threaded handler. Now people noticed and started to change the spin_lock() in the handler to spin_lock_irqsave() which affects performance or add IRQF_NOTHREAD to the interrupt request which in turn breaks RT. Fix the root cause and not the symptom and disable interrupts before invoking the force threaded handler which preserves the regular semantics and the usefulness of the interrupt force threading as a general debugging tool. For not RT this is not changing much, except that during the execution of the threaded handler interrupts are delayed until the handler returns. Vs. scheduling and softirq processing there is no difference. For RT kernels there is no issue. Fixes: 8d32a307e4fa ("genirq: Provide forced interrupt threading") Reported-by: Johan Hovold Signed-off-by: Thomas Gleixner Reviewed-by: Johan Hovold Acked-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20210317143859.513307808@linutronix.de Signed-off-by: Greg Kroah-Hartman

ext4: fix potential error in ext4_do_update_inode

2021-03-24T10:05:06+00:00

commit 7d8bd3c76da1d94b85e6c9b7007e20e980bfcfe6 upstream. If set_large_file = 1 and errors occur in ext4_handle_dirty_metadata(), the error code will be overridden, go to out_brelse to avoid this situation. Signed-off-by: Shijie Luo Link: https://lore.kernel.org/r/20210312065051.36314-1-luoshijie1@huawei.com Cc: stable@kernel.org Reviewed-by: Jan Kara Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: do not try to set xattr into ea_inode if value is empty

2021-03-24T10:05:06+00:00

commit 6b22489911b726eebbf169caee52fea52013fbdd upstream. Syzbot report a warning that ext4 may create an empty ea_inode if set an empty extent attribute to a file on the file system which is no free blocks left. WARNING: CPU: 6 PID: 10667 at fs/ext4/xattr.c:1640 ext4_xattr_set_entry+0x10f8/0x1114 fs/ext4/xattr.c:1640 ... Call trace: ext4_xattr_set_entry+0x10f8/0x1114 fs/ext4/xattr.c:1640 ext4_xattr_block_set+0x1d0/0x1b1c fs/ext4/xattr.c:1942 ext4_xattr_set_handle+0x8a0/0xf1c fs/ext4/xattr.c:2390 ext4_xattr_set+0x120/0x1f0 fs/ext4/xattr.c:2491 ext4_xattr_trusted_set+0x48/0x5c fs/ext4/xattr_trusted.c:37 __vfs_setxattr+0x208/0x23c fs/xattr.c:177 ... Now, ext4 try to store extent attribute into an external inode if ext4_xattr_block_set() return -ENOSPC, but for the case of store an empty extent attribute, store the extent entry into the extent attribute block is enough. A simple reproduce below. fallocate test.img -l 1M mkfs.ext4 -F -b 2048 -O ea_inode test.img mount test.img /mnt dd if=/dev/zero of=/mnt/foo bs=2048 count=500 setfattr -n "user.test" /mnt/foo Reported-by: syzbot+98b881fdd8ebf45ab4ae@syzkaller.appspotmail.com Fixes: 9c6e7853c531 ("ext4: reserve space for xattr entries/names") Cc: stable@kernel.org Signed-off-by: zhangyi (F) Link: https://lore.kernel.org/r/20210305120508.298465-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: find old entry again if failed to rename whiteout

2021-03-24T10:05:05+00:00

commit b7ff91fd030dc9d72ed91b1aab36e445a003af4f upstream. If we failed to add new entry on rename whiteout, we cannot reset the old->de entry directly, because the old->de could have moved from under us during make indexed dir. So find the old entry again before reset is needed, otherwise it may corrupt the filesystem as below. /dev/sda: Entry '00000001' in ??? (12) has deleted/unused inode 15. CLEARED. /dev/sda: Unattached inode 75 /dev/sda: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY. Fixes: 6b4b8e6b4ad ("ext4: fix bug for rename with RENAME_WHITEOUT") Cc: stable@vger.kernel.org Signed-off-by: zhangyi (F) Link: https://lore.kernel.org/r/20210303131703.330415-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

x86: Introduce TS_COMPAT_RESTART to fix get_nr_restart_syscall()

2021-03-24T10:05:05+00:00

commit 8c150ba2fb5995c84a7a43848250d444a3329a7d upstream. The comment in get_nr_restart_syscall() says: * The problem is that we can get here when ptrace pokes * syscall-like values into regs even if we're not in a syscall * at all. Yes, but if not in a syscall then the status & (TS_COMPAT|TS_I386_REGS_POKED) check below can't really help: - TS_COMPAT can't be set - TS_I386_REGS_POKED is only set if regs->orig_ax was changed by 32bit debugger; and even in this case get_nr_restart_syscall() is only correct if the tracee is 32bit too. Suppose that a 64bit debugger plays with a 32bit tracee and * Tracee calls sleep(2) // TS_COMPAT is set * User interrupts the tracee by CTRL-C after 1 sec and does "(gdb) call func()" * gdb saves the regs by PTRACE_GETREGS * does PTRACE_SETREGS to set %rip='func' and %orig_rax=-1 * PTRACE_CONT // TS_COMPAT is cleared * func() hits int3. * Debugger catches SIGTRAP. * Restore original regs by PTRACE_SETREGS. * PTRACE_CONT get_nr_restart_syscall() wrongly returns __NR_restart_syscall==219, the tracee calls ia32_sys_call_table[219] == sys_madvise. Add the sticky TS_COMPAT_RESTART flag which survives after return to user mode. It's going to be removed in the next step again by storing the information in the restart block. As a further cleanup it might be possible to remove also TS_I386_REGS_POKED with that. Test-case: $ cvs -d :pserver:anoncvs:anoncvs@sourceware.org:/cvs/systemtap co ptrace-tests $ gcc -o erestartsys-trap-debuggee ptrace-tests/tests/erestartsys-trap-debuggee.c --m32 $ gcc -o erestartsys-trap-debugger ptrace-tests/tests/erestartsys-trap-debugger.c -lutil $ ./erestartsys-trap-debugger Unexpected: retval 1, errno 22 erestartsys-trap-debugger: ptrace-tests/tests/erestartsys-trap-debugger.c:421 Fixes: 609c19a385c8 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Reported-by: Jan Kratochvil Signed-off-by: Oleg Nesterov Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174709.GA17895@redhat.com Signed-off-by: Greg Kroah-Hartman

x86: Move TS_COMPAT back to asm/thread_info.h

2021-03-24T10:05:05+00:00

commit 66c1b6d74cd7035e85c426f0af4aede19e805c8a upstream. Move TS_COMPAT back to asm/thread_info.h, close to TS_I386_REGS_POKED. It was moved to asm/processor.h by b9d989c7218a ("x86/asm: Move the thread_info::status field to thread_struct"), then later 37a8f7c38339 ("x86/asm: Move 'status' from thread_struct to thread_info") moved the 'status' field back but TS_COMPAT was forgotten. Preparatory patch to fix the COMPAT case for get_nr_restart_syscall() Fixes: 609c19a385c8 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Signed-off-by: Oleg Nesterov Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174649.GA17880@redhat.com Signed-off-by: Greg Kroah-Hartman

kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data()

2021-03-24T10:05:05+00:00

commit 5abbe51a526253b9f003e9a0a195638dc882d660 upstream. Preparation for fixing get_nr_restart_syscall() on X86 for COMPAT. Add a new helper which sets restart_block->fn and calls a dummy arch_set_restart_data() helper. Fixes: 609c19a385c8 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Signed-off-by: Oleg Nesterov Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174641.GA17871@redhat.com Signed-off-by: Greg Kroah-Hartman

x86/ioapic: Ignore IRQ2 again

2021-03-24T10:05:05+00:00

commit a501b048a95b79e1e34f03cac3c87ff1e9f229ad upstream. Vitaly ran into an issue with hotplugging CPU0 on an Amazon instance where the matrix allocator claimed to be out of vectors. He analyzed it down to the point that IRQ2, the PIC cascade interrupt, which is supposed to be not ever routed to the IO/APIC ended up having an interrupt vector assigned which got moved during unplug of CPU0. The underlying issue is that IRQ2 for various reasons (see commit af174783b925 ("x86: I/O APIC: Never configure IRQ2" for details) is treated as a reserved system vector by the vector core code and is not accounted as a regular vector. The Amazon BIOS has an routing entry of pin2 to IRQ2 which causes the IO/APIC setup to claim that interrupt which is granted by the vector domain because there is no sanity check. As a consequence the allocation counter of CPU0 underflows which causes a subsequent unplug to fail with: [ ... ] CPU 0 has 4294967295 vectors, 589 available. Cannot disable CPU There is another sanity check missing in the matrix allocator, but the underlying root cause is that the IO/APIC code lost the IRQ2 ignore logic during the conversion to irqdomains. For almost 6 years nobody complained about this wreckage, which might indicate that this requirement could be lifted, but for any system which actually has a PIC IRQ2 is unusable by design so any routing entry has no effect and the interrupt cannot be connected to a device anyway. Due to that and due to history biased paranoia reasons restore the IRQ2 ignore logic and treat it as non existent despite a routing entry claiming otherwise. Fixes: d32932d02e18 ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces") Reported-by: Vitaly Kuznetsov Signed-off-by: Thomas Gleixner Tested-by: Vitaly Kuznetsov Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210318192819.636943062@linutronix.de Signed-off-by: Greg Kroah-Hartman

perf/x86/intel: Fix a crash caused by zero PEBS status

2021-03-24T10:05:04+00:00

commit d88d05a9e0b6d9356e97129d4ff9942d765f46ea upstream. A repeatable crash can be triggered by the perf_fuzzer on some Haswell system. https://lore.kernel.org/lkml/7170d3b-c17f-1ded-52aa-cc6d9ae999f4@maine.edu/ For some old CPUs (HSW and earlier), the PEBS status in a PEBS record may be mistakenly set to 0. To minimize the impact of the defect, the commit was introduced to try to avoid dropping the PEBS record for some cases. It adds a check in the intel_pmu_drain_pebs_nhm(), and updates the local pebs_status accordingly. However, it doesn't correct the PEBS status in the PEBS record, which may trigger the crash, especially for the large PEBS. It's possible that all the PEBS records in a large PEBS have the PEBS status 0. If so, the first get_next_pebs_record_by_bit() in the __intel_pmu_pebs_event() returns NULL. The at = NULL. Since it's a large PEBS, the 'count' parameter must > 1. The second get_next_pebs_record_by_bit() will crash. Besides the local pebs_status, correct the PEBS status in the PEBS record as well. Fixes: 01330d7288e0 ("perf/x86: Allow zero PEBS status with only single active event") Reported-by: Vince Weaver Suggested-by: Peter Zijlstra (Intel) Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1615555298-140216-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Greg Kroah-Hartman