kernel/git/stable/linux.git/arch/um/include, branch linux-5.18.y

um: seed rng using host OS rng

2022-08-17T12:40:14+00:00

commit 0b9ba6135d7f18b82f3d8bebb55ded725ba88e0e upstream. UML generally does not provide access to special CPU instructions like RDRAND, and execution tends to be rather deterministic, with no real hardware interrupts, making good randomness really very hard, if not all together impossible. Not only is this a security eyebrow raiser, but it's also quite annoying when trying to do various pieces of UML-based automation that takes a long time to boot, if ever. Fix this by trivially calling getrandom() in the host and using that seed as "bootloader randomness", which initializes the rng immediately at UML boot. The old behavior can be restored the same way as on any other arch, by way of CONFIG_TRUST_BOOTLOADER_RANDOMNESS=n or random.trust_bootloader=0. So seen from that perspective, this just makes UML act like other archs, which is positive in its own right. Additionally, wire up arch_get_random_{int,long}() in the same way, so that reseeds can also make use of the host RNG, controllable by CONFIG_TRUST_CPU_RANDOMNESS and random.trust_cpu, per usual. Cc: stable@vger.kernel.org Acked-by: Johannes Berg Acked-By: Anton Ivanov Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman

um: Remove straying parenthesis

2022-08-17T12:40:14+00:00

commit c6496e0a4a90d8149203c16323cff3fa46e422e7 upstream. Commit e3a33af812c6 ("um: fix and optimize xor select template for CONFIG64 and timetravel mode") caused a build regression when CONFIG_XOR_BLOCKS and CONFIG_UML_TIME_TRAVEL_SUPPORT are selected. Fix it by removing the straying parenthesis. Cc: stable@vger.kernel.org Fixes: e3a33af812c6 ("um: fix and optimize xor select template for CONFIG64 and timetravel mode") Signed-off-by: Benjamin Beichler [rw: Added commit message] Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman

um: line: Use separate IRQs per line

2022-06-14T16:45:13+00:00

[ Upstream commit d5a9597d6916a76663085db984cb8fe97f0a5c56 ] Today, all possible serial lines (ssl*=) as well as all possible consoles (con*=) each share a single interrupt (with a fixed number) with others of the same type. Now, if you have two lines, say ssl0 and ssl1, and one of them is connected to an fd you cannot read (e.g. a file), but the other gets a read interrupt, then both of them get the interrupt since it's shared. Then, the read() call will return EOF, since it's a file being written and there's nothing to read (at least not at the current offset, at the end). Unfortunately, this is treated as a read error, and we close this line, losing all the possible output. It might be possible to work around this and make the IRQ sharing work, however, now that we have dynamically allocated IRQs that are easy to use, simply use that to achieve separating between the events; then there's no interrupt for that line and we never attempt the read in the first place, thus not closing the line. This manifested itself in the wifi hostap/hwsim tests where the parallel script communicates via one serial console and the kernel messages go to another (a file) and sending data on the communication console caused the kernel messages to stop flowing into the file. Reported-by: Jouni Malinen Signed-off-by: Johannes Berg Acked-By: anton ivanov Signed-off-by: Richard Weinberger Signed-off-by: Sasha Levin

um: Use asm-generic/dma-mapping.h

2022-06-09T08:30:50+00:00

commit 365719035526e8eda214a1cedb2e1c96e969a0d7 upstream. If DMA (PCI over virtio) is enabled, then some drivers may enable CONFIG_DMA_OPS as well, and then we pull in the x86 definition of get_arch_dma_ops(), which uses the dma_ops symbol, which isn't defined. Since we don't have real DMA ops nor any kind of IOMMU fix this in the simplest possible way: pull in the asm-generic file instead of inheriting the x86 one. It's not clear why those drivers that do (e.g. VDPA) "select DMA_OPS", and if they'd even work with this, but chances are nobody will be wanting to do that anyway, so fixing the build failure is good enough. Reported-by: Randy Dunlap Fixes: 68f5d3f3b654 ("um: add PCI over virtio emulation driver") Signed-off-by: Johannes Berg Tested-by: Randy Dunlap Acked-by: Randy Dunlap Cc: stable@vger.kernel.org Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman

ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP

2022-06-09T08:29:30+00:00

commit c200e4bb44e80b343c09841e7caaaca0aac5e5fa upstream. User mode linux is the last user of the PT_DTRACE flag. Using the flag to indicate single stepping is a little confusing and worse changing tsk->ptrace without locking could potentionally cause problems. So use a thread info flag with a better name instead of flag in tsk->ptrace. Remove the definition PT_DTRACE as uml is the last user. Cc: stable@vger.kernel.org Acked-by: Johannes Berg Tested-by: Kees Cook Reviewed-by: Oleg Nesterov Link: https://lkml.kernel.org/r/20220505182645.497868-3-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" Signed-off-by: Greg Kroah-Hartman

um: use fallback for random_get_entropy() instead of zero

2022-05-30T07:24:05+00:00

commit 9f13fb0cd11ed2327abff69f6501a2c124c88b5a upstream. In the event that random_get_entropy() can't access a cycle counter or similar, falling back to returning 0 is really not the best we can do. Instead, at least calling random_get_entropy_fallback() would be preferable, because that always needs to return _something_, even falling back to jiffies eventually. It's not as though random_get_entropy_fallback() is super high precision or guaranteed to be entropic, but basically anything that's not zero all the time is better than returning zero all the time. This is accomplished by just including the asm-generic code like on other architectures, which means we can get rid of the empty stub function here. Cc: Thomas Gleixner Cc: Arnd Bergmann Cc: Richard Weinberger Cc: Anton Ivanov Acked-by: Johannes Berg Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman

Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2022-04-02T02:57:03+00:00

Pull vfs updates from Al Viro: "Assorted bits and pieces" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: aio: drop needless assignment in aio_read() clean overflow checks in count_mounts() a bit seq_file: fix NULL pointer arithmetic warning uml/x86: use x86 load_unaligned_zeropad() asm/user.h: killed unused macros constify struct path argument of finish_automount()/do_add_mount() fs: Remove FIXME comment in generic_write_checks()

Merge tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml

2022-03-31T23:16:58+00:00

Pull UML updates from Richard Weinberger: - Devicetree support (for testing) - Various cleanups and fixes: UBD, port_user, uml_mconsole - Maintainer update * tag 'for-linus-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: run_helper: Write error message to kernel log on exec failure on host um: port_user: Improve error handling when port-helper is not found um: port_user: Allow setting path to port-helper using UML_PORT_HELPER envvar um: port_user: Search for in.telnetd in PATH um: clang: Strip out -mno-global-merge from USER_CFLAGS docs: UML: Mention telnetd for port channel um: Remove unused timeval_to_ns() function um: Fix uml_mconsole stop/go um: Cleanup syscall_handler_t definition/cast, fix warning uml: net: vector: fix const issue um: Fix WRITE_ZEROES in the UBD Driver um: Migrate vector drivers to NAPI um: Fix order of dtb unflatten/early init um: fix and optimize xor select template for CONFIG64 and timetravel mode um: Document dtb command line option lib/logic_iomem: correct fallback config references um: Remove duplicated include in syscalls_64.c MAINTAINERS: Update UserModeLinux entry

Merge tag 'char-misc-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2022-03-28T19:27:35+00:00

Pull char/misc and other driver updates from Greg KH: "Here is the big set of char/misc and other small driver subsystem updates for 5.18-rc1. Included in here are merges from driver subsystems which contain: - iio driver updates and new drivers - fsi driver updates - fpga driver updates - habanalabs driver updates and support for new hardware - soundwire driver updates and new drivers - phy driver updates and new drivers - coresight driver updates - icc driver updates Individual changes include: - mei driver updates - interconnect driver updates - new PECI driver subsystem added - vmci driver updates - lots of tiny misc/char driver updates All of these have been in linux-next for a while with no reported problems" * tag 'char-misc-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (556 commits) firmware: google: Properly state IOMEM dependency kgdbts: fix return value of __setup handler firmware: sysfb: fix platform-device leak in error path firmware: stratix10-svc: add missing callback parameter on RSU arm64: dts: qcom: add non-secure domain property to fastrpc nodes misc: fastrpc: Add dma handle implementation misc: fastrpc: Add fdlist implementation misc: fastrpc: Add helper function to get list and page misc: fastrpc: Add support to secure memory map dt-bindings: misc: add fastrpc domain vmid property misc: fastrpc: check before loading process to the DSP misc: fastrpc: add secure domain support dt-bindings: misc: add property to support non-secure DSP misc: fastrpc: Add support to get DSP capabilities misc: fastrpc: add support for FASTRPC_IOCTL_MEM_MAP/UNMAP misc: fastrpc: separate fastrpc device from channel context dt-bindings: nvmem: brcm,nvram: add basic NVMEM cells dt-bindings: nvmem: make "reg" property optional nvmem: brcm_nvram: parse NVRAM content into NVMEM cells nvmem: dt-bindings: Fix the error of dt-bindings check ...

Merge tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

2022-03-24T18:39:32+00:00

Pull flexible-array transformations from Gustavo Silva: "Treewide patch that replaces zero-length arrays with flexible-array members. This has been baking in linux-next for a whole development cycle" * tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: treewide: Replace zero-length arrays with flexible-array members