kernel/linux.git/drivers/char, branch v4.19.77

hwrng: core - don't wait on add_early_randomness()

2019-10-05T11:10:12+00:00

commit 78887832e76541f77169a24ac238fccb51059b63 upstream. add_early_randomness() is called by hwrng_register() when the hardware is added. If this hardware and its module are present at boot, and if there is no data available the boot hangs until data are available and can't be interrupted. For instance, in the case of virtio-rng, in some cases the host can be not able to provide enough entropy for all the guests. We can have two easy ways to reproduce the problem but they rely on misconfiguration of the hypervisor or the egd daemon: - if virtio-rng device is configured to connect to the egd daemon of the host but when the virtio-rng driver asks for data the daemon is not connected, - if virtio-rng device is configured to connect to the egd daemon of the host but the egd daemon doesn't provide data. The guest kernel will hang at boot until the virtio-rng driver provides enough data. To avoid that, call rng_get_data() in non-blocking mode (wait=0) from add_early_randomness(). Signed-off-by: Laurent Vivier Fixes: d9e797261933 ("hwrng: add randomness to system from rng...") Cc: Reviewed-by: Theodore Ts'o Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

/dev/mem: Bail out upon SIGKILL.

2019-10-05T11:10:11+00:00

commit 8619e5bdeee8b2c685d686281f2d2a6017c4bc15 upstream. syzbot found that a thread can stall for minutes inside read_mem() or write_mem() after that thread was killed by SIGKILL [1]. Reading from iomem areas of /dev/mem can be slow, depending on the hardware. While reading 2GB at one read() is legal, delaying termination of killed thread for minutes is bad. Thus, allow reading/writing /dev/mem and /dev/kmem to be preemptible and killable. [ 1335.912419][T20577] read_mem: sz=4096 count=2134565632 [ 1335.943194][T20577] read_mem: sz=4096 count=2134561536 [ 1335.978280][T20577] read_mem: sz=4096 count=2134557440 [ 1336.011147][T20577] read_mem: sz=4096 count=2134553344 [ 1336.041897][T20577] read_mem: sz=4096 count=2134549248 Theoretically, reading/writing /dev/mem and /dev/kmem can become "interruptible". But this patch chose "killable". Future patch will make them "interruptible" so that we can revert to "killable" if some program regressed. [1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e Signed-off-by: Tetsuo Handa Cc: stable Reported-by: syzbot Link: https://lore.kernel.org/r/1566825205-10703-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

tpm: Fix some name collisions with drivers/char/tpm.h

2019-09-16T06:22:05+00:00

[ Upstream commit 8ab547a2dcfac6ec184a5e036e1093eb3f7a215c ] * Rename TPM_BUFSIZE defined in drivers/char/tpm/st33zp24/st33zp24.h to ST33ZP24_BUFSIZE. * Rename TPM_BUFSIZE defined in drivers/char/tpm/tpm_i2c_infineon.c to TPM_I2C_INFINEON_BUFSIZE. * Rename TPM_RETRY in tpm_i2c_nuvoton to TPM_I2C_RETRIES. * Remove TPM_HEADER_SIZE from tpm_i2c_nuvoton. Cc: stable@vger.kernel.org Fixes: bf38b8710892 ("tpm/tpm_i2c_stm_st33: Split tpm_i2c_tpm_st33 in 2 layers (core + phy)") Fixes: aad628c1d91a ("char/tpm: Add new driver for Infineon I2C TIS TPM") Fixes: 32d33b29ba07 ("TPM: Retry SaveState command in suspend path") Signed-off-by: Jarkko Sakkinen Signed-off-by: Sasha Levin

hpet: Fix division by zero in hpet_time_div()

2019-07-31T05:27:10+00:00

commit 0c7d37f4d9b8446956e97b7c5e61173cdb7c8522 upstream. The base value in do_div() called by hpet_time_div() is truncated from unsigned long to uint32_t, resulting in a divide-by-zero exception. UBSAN: Undefined behaviour in ../drivers/char/hpet.c:572:2 division by zero CPU: 1 PID: 23682 Comm: syz-executor.3 Not tainted 4.4.184.x86_64+ #4 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 0000000000000000 b573382df1853d00 ffff8800a3287b98 ffffffff81ad7561 ffff8800a3287c00 ffffffff838b35b0 ffffffff838b3860 ffff8800a3287c20 0000000000000000 ffff8800a3287bb0 ffffffff81b8f25e ffffffff838b35a0 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [] ubsan_epilogue+0x12/0x8d lib/ubsan.c:166 [] __ubsan_handle_divrem_overflow+0x282/0x2c8 lib/ubsan.c:262 [] hpet_time_div drivers/char/hpet.c:572 [inline] [] hpet_ioctl_common drivers/char/hpet.c:663 [inline] [] hpet_ioctl_common.cold+0xa8/0xad drivers/char/hpet.c:577 [] hpet_ioctl+0xc6/0x180 drivers/char/hpet.c:676 [] vfs_ioctl fs/ioctl.c:43 [inline] [] file_ioctl fs/ioctl.c:470 [inline] [] do_vfs_ioctl+0x6e0/0xf70 fs/ioctl.c:605 [] SYSC_ioctl fs/ioctl.c:622 [inline] [] SyS_ioctl+0x94/0xc0 fs/ioctl.c:613 [] tracesys_phase2+0x90/0x95 The main C reproducer autogenerated by syzkaller, syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); memcpy((void*)0x20000100, "/dev/hpet\000", 10); syscall(__NR_openat, 0xffffffffffffff9c, 0x20000100, 0, 0); syscall(__NR_ioctl, r[0], 0x40086806, 0x40000000000000); Fix it by using div64_ul(). Signed-off-by: Kefeng Wang Signed-off-by: Zhang HongJun Cc: stable Reviewed-by: Arnd Bergmann Link: https://lore.kernel.org/r/20190711132757.130092-1-wangkefeng.wang@huawei.com Signed-off-by: Greg Kroah-Hartman

hwrng: omap - Set default quality

2019-05-31T13:46:31+00:00

[ Upstream commit 62f95ae805fa9e1e84d47d3219adddd97b2654b7 ] Newer combinations of the glibc, kernel and openssh can result in long initial startup times on OMAP devices: [ 6.671425] systemd-rc-once[102]: Creating ED25519 key; this may take some time ... [ 142.652491] systemd-rc-once[102]: Creating ED25519 key; done. due to the blocking getrandom(2) system call: [ 142.610335] random: crng init done Set the quality level for the omap hwrng driver allowing the kernel to use the hwrng as an entropy source at boot. Signed-off-by: Rouven Czerwinski Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

virtio_console: initialize vtermno value for ports

2019-05-31T13:46:29+00:00

[ Upstream commit 4b0a2c5ff7215206ea6135a405f17c5f6fca7d00 ] For regular serial ports we do not initialize value of vtermno variable. A garbage value is assigned for non console ports. The value can be observed as a random integer with [1]. [1] vim /sys/kernel/debug/virtio-ports/vport*p* This patch initialize the value of vtermno for console serial ports to '1' and regular serial ports are initiaized to '0'. Reported-by: siliu@redhat.com Signed-off-by: Pankaj Gupta Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

random: add a spinlock_t to struct batched_entropy

2019-05-31T13:46:19+00:00

[ Upstream commit b7d5dc21072cda7124d13eae2aefb7343ef94197 ] The per-CPU variable batched_entropy_uXX is protected by get_cpu_var(). This is just a preempt_disable() which ensures that the variable is only from the local CPU. It does not protect against users on the same CPU from another context. It is possible that a preemptible context reads slot 0 and then an interrupt occurs and the same value is read again. The above scenario is confirmed by lockdep if we add a spinlock: | ================================ | WARNING: inconsistent lock state | 5.1.0-rc3+ #42 Not tainted | -------------------------------- | inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. | ksoftirqd/9/56 [HC0[0]:SC1[1]:HE0:SE0] takes: | (____ptrval____) (batched_entropy_u32.lock){+.?.}, at: get_random_u32+0x3e/0xe0 | {SOFTIRQ-ON-W} state was registered at: | _raw_spin_lock+0x2a/0x40 | get_random_u32+0x3e/0xe0 | new_slab+0x15c/0x7b0 | ___slab_alloc+0x492/0x620 | __slab_alloc.isra.73+0x53/0xa0 | kmem_cache_alloc_node+0xaf/0x2a0 | copy_process.part.41+0x1e1/0x2370 | _do_fork+0xdb/0x6d0 | kernel_thread+0x20/0x30 | kthreadd+0x1ba/0x220 | ret_from_fork+0x3a/0x50 … | other info that might help us debug this: | Possible unsafe locking scenario: | | CPU0 | ---- | lock(batched_entropy_u32.lock); | | lock(batched_entropy_u32.lock); | | *** DEADLOCK *** | | stack backtrace: | Call Trace: … | kmem_cache_alloc_trace+0x20e/0x270 | ipmi_alloc_recv_msg+0x16/0x40 … | __do_softirq+0xec/0x48d | run_ksoftirqd+0x37/0x60 | smpboot_thread_fn+0x191/0x290 | kthread+0xfe/0x130 | ret_from_fork+0x3a/0x50 Add a spinlock_t to the batched_entropy data structure and acquire the lock while accessing it. Acquire the lock with disabled interrupts because this function may be used from interrupt context. Remove the batched_entropy_reset_lock lock. Now that we have a lock for the data scructure, we can access it from a remote CPU. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

random: fix CRNG initialization when random.trust_cpu=1

2019-05-31T13:46:18+00:00

[ Upstream commit fe6f1a6a8eedc1aa538fee0baa612b6a59639cf8 ] When the system boots with random.trust_cpu=1 it doesn't initialize the per-NUMA CRNGs because it skips the rest of the CRNG startup code. This means that the code from 1e7f583af67b ("random: make /dev/urandom scalable for silly userspace programs") is not used when random.trust_cpu=1. crash> dmesg | grep random: [ 0.000000] random: get_random_bytes called from start_kernel+0x94/0x530 with crng_init=0 [ 0.314029] random: crng done (trusting CPU's manufacturer) crash> print crng_node_pool $6 = (struct crng_state **) 0x0 After adding the missing call to numa_crng_init() the per-NUMA CRNGs are initialized again: crash> dmesg | grep random: [ 0.000000] random: get_random_bytes called from start_kernel+0x94/0x530 with crng_init=0 [ 0.314031] random: crng done (trusting CPU's manufacturer) crash> print crng_node_pool $1 = (struct crng_state **) 0xffff9a915f4014a0 The call to invalidate_batched_entropy() was also missing. This is important for architectures like PPC and S390 which only have the arch_get_random_seed_* functions. Fixes: 39a8883a2b98 ("random: add a config option to trust the CPU's hwrng") Signed-off-by: Jon DeVree Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ipmi:ssif: compare block number correctly for multi-part return messages

2019-05-22T05:37:43+00:00

commit 55be8658c7e2feb11a5b5b33ee031791dbd23a69 upstream. According to ipmi spec, block number is a number that is incremented, starting with 0, for each new block of message data returned using the middle transaction. Here, the 'blocknum' is data[0] which always starts from zero(0) and 'ssif_info->multi_pos' starts from 1. So, we need to add +1 to blocknum while comparing with multi_pos. Fixes: 7d6380cd40f79 ("ipmi:ssif: Fix handling of multi-part return messages"). Reported-by: Kiran Kolukuluru Signed-off-by: Kamlakant Patel Message-Id: <1556106615-18722-1-git-send-email-kamlakantp@marvell.com> [Also added a debug log if the block numbers don't match.] Signed-off-by: Corey Minyard Cc: stable@vger.kernel.org # 4.4 Signed-off-by: Greg Kroah-Hartman

ipmi: ipmi_si_hardcode.c: init si_type array to fix a crash

2019-05-16T17:41:23+00:00

[ Upstream commit a885bcfd152f97b25005298ab2d6b741aed9b49c ] The intended behavior of function ipmi_hardcode_init_one() is to default to kcs interface when no type argument is presented when initializing ipmi with hard coded addresses. However, the array of char pointers allocated on the stack by function ipmi_hardcode_init() was not inited to zeroes, so it contained stack debris. Consequently, passing the cruft stored in this array to function ipmi_hardcode_init_one() caused a crash when it was unable to detect that the char * being passed was nonsense and tried to access the address specified by the bogus pointer. The fix is simply to initialize the si_type array to zeroes, so if there were no type argument given to at the command line, function ipmi_hardcode_init_one() could properly default to the kcs interface. Signed-off-by: Tony Camuso Message-Id: <1554837603-40299-1-git-send-email-tcamuso@redhat.com> Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin