user/sven/linux.git, branch v4.4.203

Linux 4.4.203

2019-11-25T14:54:52Z

arm64: uaccess: Ensure PAN is re-enabled after unhandled uaccess fault

2019-11-25T14:54:52Z

commit 94bb804e1e6f0a9a77acf20d7c70ea141c6c821e upstream. A number of our uaccess routines ('__arch_clear_user()' and '__arch_copy_{in,from,to}_user()') fail to re-enable PAN if they encounter an unhandled fault whilst accessing userspace. For CPUs implementing both hardware PAN and UAO, this bug has no effect when both extensions are in use by the kernel. For CPUs implementing hardware PAN but not UAO, this means that a kernel using hardware PAN may execute portions of code with PAN inadvertently disabled, opening us up to potential security vulnerabilities that rely on userspace access from within the kernel which would usually be prevented by this mechanism. In other words, parts of the kernel run the same way as they would on a CPU without PAN implemented/emulated at all. For CPUs not implementing hardware PAN and instead relying on software emulation via 'CONFIG_ARM64_SW_TTBR0_PAN=y', the impact is unfortunately much worse. Calling 'schedule()' with software PAN disabled means that the next task will execute in the kernel using the page-table and ASID of the previous process even after 'switch_mm()', since the actual hardware switch is deferred until return to userspace. At this point, or if there is a intermediate call to 'uaccess_enable()', the page-table and ASID of the new process are installed. Sadly, due to the changes introduced by KPTI, this is not an atomic operation and there is a very small window (two instructions) where the CPU is configured with the page-table of the old task and the ASID of the new task; a speculative access in this state is disastrous because it would corrupt the TLB entries for the new task with mappings from the previous address space. As Pavel explains: | I was able to reproduce memory corruption problem on Broadcom's SoC | ARMv8-A like this: | | Enable software perf-events with PERF_SAMPLE_CALLCHAIN so userland's | stack is accessed and copied. | | The test program performed the following on every CPU and forking | many processes: | | unsigned long *map = mmap(NULL, PAGE_SIZE, PROT_READ|PROT_WRITE, | MAP_SHARED | MAP_ANONYMOUS, -1, 0); | map[0] = getpid(); | sched_yield(); | if (map[0] != getpid()) { | fprintf(stderr, "Corruption detected!"); | } | munmap(map, PAGE_SIZE); | | From time to time I was getting map[0] to contain pid for a | different process. Ensure that PAN is re-enabled when returning after an unhandled user fault from our uaccess routines. Cc: Catalin Marinas Reviewed-by: Mark Rutland Tested-by: Mark Rutland Cc: Fixes: 338d4f49d6f7 ("arm64: kernel: Add support for Privileged Access Never") Signed-off-by: Pavel Tatashin [will: rewrote commit message] [will: backport for 4.4.y stable kernels] Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

spi: rockchip: initialize dma_slave_config properly

2019-11-25T14:54:51Z

[ Upstream commit dd8fd2cbc73f8650f651da71fc61a6e4f30c1566 ] The rxconf and txconf structs are allocated on the stack, so make sure we zero them before filling out the relevant fields. Signed-off-by: Huibin Hong Signed-off-by: Emil Renner Berthing Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

mac80211: minstrel: fix CCK rate group streams value

2019-11-25T14:54:51Z

[ Upstream commit 80df9be67c44cb636bbc92caeddad8caf334c53c ] Fixes a harmless underflow issue when CCK rates are actively being used Signed-off-by: Felix Fietkau Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

hwmon: (pwm-fan) Silence error on probe deferral

2019-11-25T14:54:51Z

[ Upstream commit 9f67f7583e77fe5dc57aab3a6159c2642544eaad ] Probe deferrals aren't actual errors, so silence the error message in case the PWM cannot yet be acquired. Signed-off-by: Thierry Reding Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin

ARM: 8802/1: Call syscall_trace_exit even when system call skipped

2019-11-25T14:54:51Z

[ Upstream commit f18aef742c8fbd68e280dff0a63ba0ca6ee8ad85 ] On at least x86 and ARM64, and as documented in the ptrace man page a skipped system call will still cause a syscall exit ptrace stop. Previous to this commit 32-bit ARM did not, resulting in strace being confused when seccomp skips system calls. This change also impacts programs that use ptrace to skip system calls. Fixes: ad75b51459ae ("ARM: 7579/1: arch/allow a scno of -1 to not cause a SIGILL") Signed-off-by: Timothy E Baldwin Signed-off-by: Eugene Syromyatnikov Reviewed-by: Kees Cook Tested-by: Kees Cook Tested-by: Eugene Syromyatnikov Signed-off-by: Russell King Signed-off-by: Sasha Levin

spi: spidev: Fix OF tree warning logic

2019-11-25T14:54:50Z

[ Upstream commit 605b3bec73cbd74b4ac937b580cd0b47d1300484 ] spidev will make a big fuss if a device tree node binds a device by using "spidev" as the node's compatible property. However, the logic for this isn't looking for "spidev" in the compatible, but rather checking that the device is NOT compatible with spidev's list of devices. This causes a false positive if a device not named "rohm,dh2228fv", etc. binds to spidev, even if a means other than putting "spidev" in the device tree was used. E.g., the sysfs driver_override attribute. Signed-off-by: Trent Piepho Reviewed-by: Jan KundrÃ¡t Tested-by: Jan KundrÃ¡t Reviewed-by: Geert Uytterhoeven Signed-off-by: Mark Brown Signed-off-by: Sasha Levin

gpio: syscon: Fix possible NULL ptr usage

2019-11-25T14:54:50Z

[ Upstream commit 70728c29465bc4bfa7a8c14304771eab77e923c7 ] The priv->data->set can be NULL while flags contains GPIO_SYSCON_FEAT_OUT and chip->set is valid pointer. This happens in case the controller uses the default GPIO setter. Always use chip->set to access the setter to avoid possible NULL pointer dereferencing. Signed-off-by: Marek Vasut Signed-off-by: Linus Walleij Signed-off-by: Sasha Levin

x86/kexec: Correct KEXEC_BACKUP_SRC_END off-by-one error

2019-11-25T14:54:49Z

[ Upstream commit 51fbf14f2528a8c6401290e37f1c893a2412f1d3 ] The only use of KEXEC_BACKUP_SRC_END is as an argument to walk_system_ram_res(): int crash_load_segments(struct kimage *image) { ... walk_system_ram_res(KEXEC_BACKUP_SRC_START, KEXEC_BACKUP_SRC_END, image, determine_backup_region); walk_system_ram_res() expects "start, end" arguments that are inclusive, i.e., the range to be walked includes both the start and end addresses. KEXEC_BACKUP_SRC_END was previously defined as (640 * 1024UL), which is the first address *past* the desired 0-640KB range. Define KEXEC_BACKUP_SRC_END as (640 * 1024UL - 1) so the KEXEC_BACKUP_SRC region is [0-0x9ffff], not [0-0xa0000]. Fixes: dd5f726076cc ("kexec: support for kexec on panic using new system call") Signed-off-by: Bjorn Helgaas Signed-off-by: Borislav Petkov CC: "H. Peter Anvin" CC: Andrew Morton CC: Brijesh Singh CC: Greg Kroah-Hartman CC: Ingo Molnar CC: Lianbo Jiang CC: Takashi Iwai CC: Thomas Gleixner CC: Tom Lendacky CC: Vivek Goyal CC: baiyaowei@cmss.chinamobile.com CC: bhe@redhat.com CC: dan.j.williams@intel.com CC: dyoung@redhat.com CC: kexec@lists.infradead.org Link: http://lkml.kernel.org/r/153805811578.1157.6948388946904655969.stgit@bhelgaas-glaptop.roam.corp.google.com Signed-off-by: Sasha Levin

media: cx231xx: fix potential sign-extension overflow on large shift

2019-11-25T14:54:49Z

[ Upstream commit 32ae592036d7aeaabcccb2b1715373a68639a768 ] Shifting the u8 value[3] by an int can lead to sign-extension overflow. For example, if value[3] is 0xff and the shift is 24 then it is promoted to int and then the top bit is sign-extended so that all upper 32 bits are set. Fix this by casting value[3] to a u32 before the shift. Detected by CoverityScan, CID#1016522 ("Unintended sign extension") Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver") Signed-off-by: Colin Ian King Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin