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2019-05-14Merge tag 'modules-for-v5.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: - Use a separate table to store symbol types instead of hijacking fields in struct Elf_Sym - Trivial code cleanups * tag 'modules-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: add stubs for within_module functions kallsyms: store type information in its own array vmlinux.lds.h: drop unused __vermagic
2019-05-09Merge branch 'next-integrity' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull intgrity updates from James Morris: "This contains just three patches, the remainder were either included in other pull requests (eg. audit, lockdown) or will be upstreamed via other subsystems (eg. kselftests, Power). Included here is one bug fix, one documentation update, and extending the x86 IMA arch policy rules to coordinate the different kernel module signature verification methods" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: doc/kernel-parameters.txt: Deprecate ima_appraise_tcb x86/ima: add missing include x86/ima: require signed kernel modules
2019-04-30modules: Use vmalloc special flagRick Edgecombe
Use new flag for handling freeing of special permissioned memory in vmalloc and remove places where memory was set RW before freeing which is no longer needed. Since freeing of VM_FLUSH_RESET_PERMS memory is not supported in an interrupt by vmalloc, the freeing of init sections is moved to a work queue. Instead of call_rcu it now uses synchronize_rcu() in the work queue. Lastly, there is now a WARN_ON in module_memfree since it should not be called in an interrupt with special memory as is required for VM_FLUSH_RESET_PERMS. Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <akpm@linux-foundation.org> Cc: <ard.biesheuvel@linaro.org> Cc: <deneen.t.dock@intel.com> Cc: <kernel-hardening@lists.openwall.com> Cc: <kristen@linux.intel.com> Cc: <linux_dti@icloud.com> Cc: <will.deacon@arm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jessica Yu <jeyu@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@surriel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-18-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/modules: Avoid breaking W^X while loading modulesNadav Amit
When modules and BPF filters are loaded, there is a time window in which some memory is both writable and executable. An attacker that has already found another vulnerability (e.g., a dangling pointer) might be able to exploit this behavior to overwrite kernel code. Prevent having writable executable PTEs in this stage. In addition, avoiding having W+X mappings can also slightly simplify the patching of modules code on initialization (e.g., by alternatives and static-key), as would be done in the next patch. This was actually the main motivation for this patch. To avoid having W+X mappings, set them initially as RW (NX) and after they are set as RO set them as X as well. Setting them as executable is done as a separate step to avoid one core in which the old PTE is cached (hence writable), and another which sees the updated PTE (executable), which would break the W^X protection. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <akpm@linux-foundation.org> Cc: <ard.biesheuvel@linaro.org> Cc: <deneen.t.dock@intel.com> Cc: <kernel-hardening@lists.openwall.com> Cc: <kristen@linux.intel.com> Cc: <linux_dti@icloud.com> Cc: <will.deacon@arm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jessica Yu <jeyu@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Rik van Riel <riel@surriel.com> Link: https://lkml.kernel.org/r/20190426001143.4983-12-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-03-28kallsyms: store type information in its own arrayEugene Loh
When a module is loaded, its symbols' Elf_Sym information is stored in a symtab. Further, type information is also captured. Since Elf_Sym has no type field, historically the st_info field has been hijacked for storing type: st_info was overwritten. commit 5439c985c5a83a8419f762115afdf560ab72a452 ("module: Overwrite st_size instead of st_info") changes that practice, as its one-liner indicates. Unfortunately, this change overwrites symbol size, information that a tool like DTrace expects to find. Allocate a typetab array to store type information so that no Elf_Sym field needs to be overwritten. Fixes: 5439c985c5a8 ("module: Overwrite st_size instead of st_info") Signed-off-by: Eugene Loh <eugene.loh@oracle.com> Reviewed-by: Nick Alcock <nick.alcock@oracle.com> [jeyu: renamed typeoff -> typeoffs ] Signed-off-by: Jessica Yu <jeyu@kernel.org>
2019-03-27x86/ima: require signed kernel modulesMimi Zohar
Have the IMA architecture specific policy require signed kernel modules on systems with secure boot mode enabled; and coordinate the different signature verification methods, so only one signature is required. Requiring appended kernel module signatures may be configured, enabled on the boot command line, or with this patch enabled in secure boot mode. This patch defines set_module_sig_enforced(). To coordinate between appended kernel module signatures and IMA signatures, only define an IMA MODULE_CHECK policy rule if CONFIG_MODULE_SIG is not enabled. A custom IMA policy may still define and require an IMA signature. Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Jessica Yu <jeyu@kernel.org>
2019-03-07dynamic_debug: add static inline stub for ddebug_add_moduleRasmus Villemoes
For symmetry with ddebug_remove_module, and to avoid a bit of ifdeffery in module.c, move the declaration of ddebug_add_module inside #if defined(CONFIG_DYNAMIC_DEBUG) and add a corresponding no-op stub in the #else branch. Link: http://lkml.kernel.org/r/20190212214150.4807-10-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Jason Baron <jbaron@akamai.com> Cc: David Sterba <dsterba@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Petr Mladek <pmladek@suse.com> Cc: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-07dynamic_debug: move pr_err from module.c to ddebug_add_moduleRasmus Villemoes
This serves two purposes: First, we get a diagnostic if (though extremely unlikely), any of the calls of ddebug_add_module for built-in code fails, effectively disabling dynamic_debug. Second, I want to make struct _ddebug opaque, and avoid accessing any of its members outside dynamic_debug.[ch]. Link: http://lkml.kernel.org/r/20190212214150.4807-9-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Jason Baron <jbaron@akamai.com> Cc: David Sterba <dsterba@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Petr Mladek <pmladek@suse.com> Cc: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-06jump_label: move 'asm goto' support test to KconfigMasahiro Yamada
Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label". The jump label is controlled by HAVE_JUMP_LABEL, which is defined like this: #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) # define HAVE_JUMP_LABEL #endif We can improve this by testing 'asm goto' support in Kconfig, then make JUMP_LABEL depend on CC_HAS_ASM_GOTO. Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will match to the real kernel capability. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
2018-12-28Merge tag 'driver-core-4.21-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of driver core patches for 4.21-rc1. It's not really big, just a number of small changes for some reported issues, some documentation updates to hopefully make it harder for people to abuse the driver model, and some other minor cleanups. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: mm, memory_hotplug: update a comment in unregister_memory() component: convert to DEFINE_SHOW_ATTRIBUTE sysfs: Disable lockdep for driver bind/unbind files driver core: Add missing dev->bus->need_parent_lock checks kobject: return error code if writing /sys/.../uevent fails driver core: Move async_synchronize_full call driver core: platform: Respect return code of platform_device_register_full() kref/kobject: Improve documentation drivers/base/memory.c: Use DEVICE_ATTR_RO and friends driver core: Replace simple_strto{l,ul} by kstrtou{l,ul} kernfs: Improve kernfs_notify() poll notification latency kobject: Fix warnings in lib/kobject_uevent.c kobject: drop unnecessary cast "%llu" for u64 driver core: fix comments for device_block_probing() driver core: Replace simple_strtol by kstrtoint
2018-12-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) New ipset extensions for matching on destination MAC addresses, from Stefano Brivio. 2) Add ipv4 ttl and tos, plus ipv6 flow label and hop limit offloads to nfp driver. From Stefano Brivio. 3) Implement GRO for plain UDP sockets, from Paolo Abeni. 4) Lots of work from Michał Mirosław to eliminate the VLAN_TAG_PRESENT bit so that we could support the entire vlan_tci value. 5) Rework the IPSEC policy lookups to better optimize more usecases, from Florian Westphal. 6) Infrastructure changes eliminating direct manipulation of SKB lists wherever possible, and to always use the appropriate SKB list helpers. This work is still ongoing... 7) Lots of PHY driver and state machine improvements and simplifications, from Heiner Kallweit. 8) Various TSO deferral refinements, from Eric Dumazet. 9) Add ntuple filter support to aquantia driver, from Dmitry Bogdanov. 10) Batch dropping of XDP packets in tuntap, from Jason Wang. 11) Lots of cleanups and improvements to the r8169 driver from Heiner Kallweit, including support for ->xmit_more. This driver has been getting some much needed love since he started working on it. 12) Lots of new forwarding selftests from Petr Machata. 13) Enable VXLAN learning in mlxsw driver, from Ido Schimmel. 14) Packed ring support for virtio, from Tiwei Bie. 15) Add new Aquantia AQtion USB driver, from Dmitry Bezrukov. 16) Add XDP support to dpaa2-eth driver, from Ioana Ciocoi Radulescu. 17) Implement coalescing on TCP backlog queue, from Eric Dumazet. 18) Implement carrier change in tun driver, from Nicolas Dichtel. 19) Support msg_zerocopy in UDP, from Willem de Bruijn. 20) Significantly improve garbage collection of neighbor objects when the table has many PERMANENT entries, from David Ahern. 21) Remove egdev usage from nfp and mlx5, and remove the facility completely from the tree as it no longer has any users. From Oz Shlomo and others. 22) Add a NETDEV_PRE_CHANGEADDR so that drivers can veto the change and therefore abort the operation before the commit phase (which is the NETDEV_CHANGEADDR event). From Petr Machata. 23) Add indirect call wrappers to avoid retpoline overhead, and use them in the GRO code paths. From Paolo Abeni. 24) Add support for netlink FDB get operations, from Roopa Prabhu. 25) Support bloom filter in mlxsw driver, from Nir Dotan. 26) Add SKB extension infrastructure. This consolidates the handling of the auxiliary SKB data used by IPSEC and bridge netfilter, and is designed to support the needs to MPTCP which could be integrated in the future. 27) Lots of XDP TX optimizations in mlx5 from Tariq Toukan. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1845 commits) net: dccp: fix kernel crash on module load drivers/net: appletalk/cops: remove redundant if statement and mask bnx2x: Fix NULL pointer dereference in bnx2x_del_all_vlans() on some hw net/net_namespace: Check the return value of register_pernet_subsys() net/netlink_compat: Fix a missing check of nla_parse_nested ieee802154: lowpan_header_create check must check daddr net/mlx4_core: drop useless LIST_HEAD mlxsw: spectrum: drop useless LIST_HEAD net/mlx5e: drop useless LIST_HEAD iptunnel: Set tun_flags in the iptunnel_metadata_reply from src net/mlx5e: fix semicolon.cocci warnings staging: octeon: fix build failure with XFRM enabled net: Revert recent Spectre-v1 patches. can: af_can: Fix Spectre v1 vulnerability packet: validate address length if non-zero nfc: af_nfc: Fix Spectre v1 vulnerability phonet: af_phonet: Fix Spectre v1 vulnerability net: core: Fix Spectre v1 vulnerability net: minor cleanup in skb_ext_add() net: drop the unused helper skb_ext_get() ...
2018-12-27Merge tag 'modules-for-v4.21' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: - Some modules-related kallsyms cleanups and a kallsyms fix for ARM. - Include keys from the secondary keyring in module signature verification. * tag 'modules-for-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: ARM: module: Fix function kallsyms on Thumb-2 module: Overwrite st_size instead of st_info module: make it clearer when we're handling kallsyms symbols vs exported symbols modsign: use all trusted keys to verify module signature
2018-12-18bpf: support raw tracepoints in modulesMatt Mullins
Distributions build drivers as modules, including network and filesystem drivers which export numerous tracepoints. This enables bpf(BPF_RAW_TRACEPOINT_OPEN) to attach to those tracepoints. Signed-off-by: Matt Mullins <mmullins@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-12-14ARM: module: Fix function kallsyms on Thumb-2Vincent Whitchurch
Thumb-2 functions have the lowest bit set in the symbol value in the symtab. When kallsyms are generated for the vmlinux, the kallsyms are generated from the output of nm, and nm clears the lowest bit. $ arm-linux-gnueabihf-readelf -a vmlinux | grep show_interrupts 95947: 8015dc89 686 FUNC GLOBAL DEFAULT 2 show_interrupts $ arm-linux-gnueabihf-nm vmlinux | grep show_interrupts 8015dc88 T show_interrupts $ cat /proc/kallsyms | grep show_interrupts 8015dc88 T show_interrupts However, for modules, the kallsyms uses the values in the symbol table without modification, so for functions in modules, the lowest bit is set in kallsyms. $ arm-linux-gnueabihf-readelf -a drivers/net/tun.ko | grep tun_get_socket 333: 00002d4d 36 FUNC GLOBAL DEFAULT 1 tun_get_socket $ arm-linux-gnueabihf-nm drivers/net/tun.ko | grep tun_get_socket 00002d4c T tun_get_socket $ cat /proc/kallsyms | grep tun_get_socket 7f802d4d t tun_get_socket [tun] Because of this, the symbol+offset of the crashing instruction shown in oopses is incorrect when the crash is in a module. For example, given a tun_get_socket which starts like this, 00002d4c <tun_get_socket>: 2d4c: 6943 ldr r3, [r0, #20] 2d4e: 4a07 ldr r2, [pc, #28] 2d50: 4293 cmp r3, r2 a crash when tun_get_socket is called with NULL results in: PC is at tun_xdp+0xa3/0xa4 [tun] pc : [<7f802d4c>] As can be seen, the "PC is at" line reports the wrong symbol name, and the symbol+offset will point to the wrong source line if it is passed to gdb. To solve this, add a way for archs to fixup the reading of these module kallsyms values, and use that to clear the lowest bit for function symbols on Thumb-2. After the fix: # cat /proc/kallsyms | grep tun_get_socket 7f802d4c t tun_get_socket [tun] PC is at tun_get_socket+0x0/0x24 [tun] pc : [<7f802d4c>] Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-12-14module: Overwrite st_size instead of st_infoVincent Whitchurch
st_info is currently overwritten after relocation and used to store the elf_type(). However, we're going to need it fix kallsyms on ARM's Thumb-2 kernels, so preserve st_info and overwrite the st_size field instead. st_size is neither used by the module core nor by any architecture. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-12-06kobject: return error code if writing /sys/.../uevent failsPeter Rajnoha
Propagate error code back to userspace if writing the /sys/.../uevent file fails. Before, the write operation always returned with success, even if we failed to recognize the input string or if we failed to generate the uevent itself. With the error codes properly propagated back to userspace, we are able to react in userspace accordingly by not assuming and awaiting a uevent that is not delivered. Signed-off-by: Peter Rajnoha <prajnoha@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-29module: make it clearer when we're handling kallsyms symbols vs exported symbolsJessica Yu
The module loader internally works with both exported symbols represented as struct kernel_symbol, as well as Elf symbols from a module's symbol table. It's hard to distinguish sometimes which type of symbol we're handling given that some helper function names are not consistent or helpful. Take get_ksymbol() for instance - are we looking for an exported symbol or a kallsyms symbol here? Or symname() and kernel_symbol_name() - which function handles an exported symbol and which one an Elf symbol? Clean up and unify the function naming scheme a bit to make it clear which kind of symbol we're handling. This change only affects static functions internal to the module loader. Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-11-27modules: Replace synchronize_sched() and call_rcu_sched()Paul E. McKenney
Now that synchronize_rcu() waits for preempt-disable regions of code as well as RCU read-side critical sections, synchronize_sched() can be replaced by synchronize_rcu(). Similarly, call_rcu_sched() can be replaced by call_rcu(). This commit therefore makes these changes. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com> Acked-by: Jessica Yu <jeyu@kernel.org>
2018-09-27jump_table: Move entries into ro_after_init regionArd Biesheuvel
The __jump_table sections emitted into the core kernel and into each module consist of statically initialized references into other parts of the code, and with the exception of entries that point into init code, which are defused at post-init time, these data structures are never modified. So let's move them into the ro_after_init section, to prevent them from being corrupted inadvertently by buggy code, or deliberately by an attacker. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Jessica Yu <jeyu@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: Arnd Bergmann <arnd@arndb.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Link: https://lkml.kernel.org/r/20180919065144.25010-9-ard.biesheuvel@linaro.org
2018-08-22module: use relative references for __ksymtab entriesArd Biesheuvel
An ordinary arm64 defconfig build has ~64 KB worth of __ksymtab entries, each consisting of two 64-bit fields containing absolute references, to the symbol itself and to a char array containing its name, respectively. When we build the same configuration with KASLR enabled, we end up with an additional ~192 KB of relocations in the .init section, i.e., one 24 byte entry for each absolute reference, which all need to be processed at boot time. Given how the struct kernel_symbol that describes each entry is completely local to module.c (except for the references emitted by EXPORT_SYMBOL() itself), we can easily modify it to contain two 32-bit relative references instead. This reduces the size of the __ksymtab section by 50% for all 64-bit architectures, and gets rid of the runtime relocations entirely for architectures implementing KASLR, either via standard PIE linking (arm64) or using custom host tools (x86). Note that the binary search involving __ksymtab contents relies on each section being sorted by symbol name. This is implemented based on the input section names, not the names in the ksymtab entries, so this patch does not interfere with that. Given that the use of place-relative relocations requires support both in the toolchain and in the module loader, we cannot enable this feature for all architectures. So make it dependent on whether CONFIG_HAVE_ARCH_PREL32_RELOCATIONS is defined. Link: http://lkml.kernel.org/r/20180704083651.24360-4-ard.biesheuvel@linaro.org Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Jessica Yu <jeyu@kernel.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Will Deacon <will.deacon@arm.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morris <james.morris@microsoft.com> Cc: James Morris <jmorris@namei.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Nicolas Pitre <nico@linaro.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Russell King <linux@armlinux.org.uk> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17Merge tag 'modules-for-v4.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: "Summary of modules changes for the 4.19 merge window: - Fix modules kallsyms for livepatch. Livepatch modules can have SHN_UNDEF symbols in their module symbol tables for later symbol resolution, but kallsyms shouldn't be returning these symbols - Some code cleanups and minor reshuffling in load_module() were done to log the module name when module signature verification fails" * tag 'modules-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: kernel/module: Use kmemdup to replace kmalloc+memcpy ARM: module: fix modsign build error modsign: log module name in the event of an error module: replace VMLINUX_SYMBOL_STR() with __stringify() or string literal module: print sensible error code module: setup load info before module_sig_check() module: make it clear when we're handling the module copy in info->hdr module: exclude SHN_UNDEF symbols from kallsyms api
2018-08-02kernel/module: Use kmemdup to replace kmalloc+memcpyzhong jiang
we prefer to the kmemdup rather than kmalloc+memcpy. so just replace them. Signed-off-by: zhong jiang <zhongjiang@huawei.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-07-16module: replace the existing LSM hook in init_moduleMimi Zohar
Both the init_module and finit_module syscalls call either directly or indirectly the security_kernel_read_file LSM hook. This patch replaces the direct call in init_module with a call to the new security_kernel_load_data hook and makes the corresponding changes in SELinux, LoadPin, and IMA. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Kees Cook <keescook@chromium.org> Acked-by: Jessica Yu <jeyu@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-02modsign: log module name in the event of an errorJessica Yu
Now that we have the load_info struct all initialized (including info->name, which contains the name of the module) before module_sig_check(), make the load_info struct and hence module name available to mod_verify_sig() so that we can log the module name in the event of an error. Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-25module: replace VMLINUX_SYMBOL_STR() with __stringify() or string literalMasahiro Yamada
With the special case handling for Blackfin and Metag was removed by commit 94e58e0ac312 ("export.h: remove code for prefixing symbols with underscore"), VMLINUX_SYMBOL_STR() is now equivalent to __stringify(). Replace the remaining usages to prepare for the entire removal of VMLINUX_SYMBOL_STR(). Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-25module: print sensible error codeJason A. Donenfeld
Printing "err 0" to the user in the warning message is not particularly useful, especially when this gets transformed into a -ENOENT for the remainder of the call chain. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-22module: setup load info before module_sig_check()Jessica Yu
We want to be able to log the module name in early error messages, such as when module signature verification fails. Previously, the module name is set in layout_and_allocate(), meaning that any error messages that happen before (such as those in module_sig_check()) won't be logged with a module name, which isn't terribly helpful. In order to do this, reshuffle the order in load_module() and set up load info earlier so that we can log the module name along with these error messages. This requires splitting rewrite_section_headers() out of setup_load_info(). While we're at it, clean up and split up the operations done in layout_and_allocate(), setup_load_info(), and rewrite_section_headers() more cleanly so these functions only perform what their names suggest. Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-22module: make it clear when we're handling the module copy in info->hdrJessica Yu
In load_module(), it's not always clear whether we're handling the temporary module copy in info->hdr (which is freed at the end of load_module()) or if we're handling the module already allocated and copied to it's final place. Adding an info->mod field and using it whenever we're handling the temporary copy makes that explicitly clear. Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-18module: exclude SHN_UNDEF symbols from kallsyms apiJessica Yu
Livepatch modules are special in that we preserve their entire symbol tables in order to be able to apply relocations after module load. The unwanted side effect of this is that undefined (SHN_UNDEF) symbols of livepatch modules are accessible via the kallsyms api and this can confuse symbol resolution in livepatch (klp_find_object_symbol()) and cause subtle bugs in livepatch. Have the module kallsyms api skip over SHN_UNDEF symbols. These symbols are usually not available for normal modules anyway as we cut down their symbol tables to just the core (non-undefined) symbols, so this should really just affect livepatch modules. Note that this patch doesn't affect the display of undefined symbols in /proc/kallsyms. Reported-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-06-16Merge tag 'modules-for-v4.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull module updates from Jessica Yu: "Minor code cleanup and also allow sig_enforce param to be shown in sysfs with CONFIG_MODULE_SIG_FORCE" * tag 'modules-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: Allow to always show the status of modsign module: Do not access sig_enforce directly
2018-06-06Merge tag 'overflow-v4.18-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull overflow updates from Kees Cook: "This adds the new overflow checking helpers and adds them to the 2-factor argument allocators. And this adds the saturating size helpers and does a treewide replacement for the struct_size() usage. Additionally this adds the overflow testing modules to make sure everything works. I'm still working on the treewide replacements for allocators with "simple" multiplied arguments: *alloc(a * b, ...) -> *alloc_array(a, b, ...) and *zalloc(a * b, ...) -> *calloc(a, b, ...) as well as the more complex cases, but that's separable from this portion of the series. I expect to have the rest sent before -rc1 closes; there are a lot of messy cases to clean up. Summary: - Introduce arithmetic overflow test helper functions (Rasmus) - Use overflow helpers in 2-factor allocators (Kees, Rasmus) - Introduce overflow test module (Rasmus, Kees) - Introduce saturating size helper functions (Matthew, Kees) - Treewide use of struct_size() for allocators (Kees)" * tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: treewide: Use struct_size() for devm_kmalloc() and friends treewide: Use struct_size() for vmalloc()-family treewide: Use struct_size() for kmalloc()-family device: Use overflow helpers for devm_kmalloc() mm: Use overflow helpers in kvmalloc() mm: Use overflow helpers in kmalloc_array*() test_overflow: Add memory allocation overflow tests overflow.h: Add allocation size calculation helpers test_overflow: Report test failures test_overflow: macrofy some more, do more tests for free lib: add runtime test of check_*_overflow functions compiler.h: enable builtin overflow checkers and add fallback code
2018-06-06treewide: Use struct_size() for kmalloc()-familyKees Cook
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; void *entry[]; }; instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL); This patch makes the changes for kmalloc()-family (and kvmalloc()-family) uses. It was done via automatic conversion with manual review for the "CHECKME" non-standard cases noted below, using the following Coccinelle script: // pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len * // sizeof *pkey_cache->table, GFP_KERNEL); @@ identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc"; expression GFP; identifier VAR, ELEMENT; expression COUNT; @@ - alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP) + alloc(struct_size(VAR, ELEMENT, COUNT), GFP) // mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL); @@ identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc"; expression GFP; identifier VAR, ELEMENT; expression COUNT; @@ - alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP) + alloc(struct_size(VAR, ELEMENT, COUNT), GFP) // Same pattern, but can't trivially locate the trailing element name, // or variable name. @@ identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc"; expression GFP; expression SOMETHING, COUNT, ELEMENT; @@ - alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP) + alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-05-11init: fix false positives in W+X checkingJeffrey Hugo
load_module() creates W+X mappings via __vmalloc_node_range() (from layout_and_allocate()->move_module()->module_alloc()) by using PAGE_KERNEL_EXEC. These mappings are later cleaned up via "call_rcu_sched(&freeinit->rcu, do_free_init)" from do_init_module(). This is a problem because call_rcu_sched() queues work, which can be run after debug_checkwx() is run, resulting in a race condition. If hit, the race results in a nasty splat about insecure W+X mappings, which results in a poor user experience as these are not the mappings that debug_checkwx() is intended to catch. This issue is observed on multiple arm64 platforms, and has been artificially triggered on an x86 platform. Address the race by flushing the queued work before running the arch-defined mark_rodata_ro() which then calls debug_checkwx(). Link: http://lkml.kernel.org/r/1525103946-29526-1-git-send-email-jhugo@codeaurora.org Fixes: e1a58320a38d ("x86/mm: Warn on W^X mappings") Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org> Reported-by: Timur Tabi <timur@codeaurora.org> Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Laura Abbott <labbott@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-18module: Fix display of wrong module .text addressThomas Richter
Reading file /proc/modules shows the correct address: [root@s35lp76 ~]# cat /proc/modules | egrep '^qeth_l2' qeth_l2 94208 1 - Live 0x000003ff80401000 and reading file /sys/module/qeth_l2/sections/.text [root@s35lp76 ~]# cat /sys/module/qeth_l2/sections/.text 0x0000000018ea8363 displays a random address. This breaks the perf tool which uses this address on s390 to calculate start of .text section in memory. Fix this by printing the correct (unhashed) address. Thanks to Jessica Yu for helping on this. Fixes: ef0010a30935 ("vsprintf: don't use 'restricted_pointer()' when not restricting") Cc: <stable@vger.kernel.org> # v4.15+ Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Cc: Jessica Yu <jeyu@kernel.org> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-04-16module: Allow to always show the status of modsignJia Zhang
The sig_enforce parameter could be always shown to reflect the current status of signature enforcement. For the case of CONFIG_MODULE_SIG_FORCE=y, this modification doesn't do anything, since sig_enforce can only be enabled, and not disabled, even via the kernel cmdline. Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com> [jeyu: reworded commit message to provide clarification] Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-04-16module: Do not access sig_enforce directlyJia Zhang
Call is_module_sig_enforced() instead. Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-04-02Merge tag 'arch-removal' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pul removal of obsolete architecture ports from Arnd Bergmann: "This removes the entire architecture code for blackfin, cris, frv, m32r, metag, mn10300, score, and tile, including the associated device drivers. I have been working with the (former) maintainers for each one to ensure that my interpretation was right and the code is definitely unused in mainline kernels. Many had fond memories of working on the respective ports to start with and getting them included in upstream, but also saw no point in keeping the port alive without any users. In the end, it seems that while the eight architectures are extremely different, they all suffered the same fate: There was one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem, which was more costly than licensing newer off-the-shelf CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems that all the SoC product lines are still around, but have not used the custom CPU architectures for several years at this point. In contrast, CPU instruction sets that remain popular and have actively maintained kernel ports tend to all be used across multiple licensees. [ See the new nds32 port merged in the previous commit for the next generation of "one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem" - Linus ] The removal came out of a discussion that is now documented at https://lwn.net/Articles/748074/. Unlike the original plans, I'm not marking any ports as deprecated but remove them all at once after I made sure that they are all unused. Some architectures (notably tile, mn10300, and blackfin) are still being shipped in products with old kernels, but those products will never be updated to newer kernel releases. After this series, we still have a few architectures without mainline gcc support: - unicore32 and hexagon both have very outdated gcc releases, but the maintainers promised to work on providing something newer. At least in case of hexagon, this will only be llvm, not gcc. - openrisc, risc-v and nds32 are still in the process of finishing their support or getting it added to mainline gcc in the first place. They all have patched gcc-7.3 ports that work to some degree, but complete upstream support won't happen before gcc-8.1. Csky posted their first kernel patch set last week, their situation will be similar [ Palmer Dabbelt points out that RISC-V support is in mainline gcc since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]" This really says it all: 2498 files changed, 95 insertions(+), 467668 deletions(-) * tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits) MAINTAINERS: UNICORE32: Change email account staging: iio: remove iio-trig-bfin-timer driver tty: hvc: remove tile driver tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers serial: remove tile uart driver serial: remove m32r_sio driver serial: remove blackfin drivers serial: remove cris/etrax uart drivers usb: Remove Blackfin references in USB support usb: isp1362: remove blackfin arch glue usb: musb: remove blackfin port usb: host: remove tilegx platform glue pwm: remove pwm-bfin driver i2c: remove bfin-twi driver spi: remove blackfin related host drivers watchdog: remove bfin_wdt driver can: remove bfin_can driver mmc: remove bfin_sdh driver input: misc: remove blackfin rotary driver input: keyboard: remove bf54x driver ...
2018-03-16mm: remove blackfin MPU supportArnd Bergmann
The CONFIG_MPU option was only defined on blackfin, and that architecture is now being removed, so the respective code can be simplified. A lot of other microcontrollers have an MPU, but I suspect that if we want to bring that support back, we'd do it differently anyway. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-08module: propagate error in modules_open()Leon Yu
otherwise kernel can oops later in seq_release() due to dereferencing null file->private_data which is only set if seq_open() succeeds. BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 IP: seq_release+0xc/0x30 Call Trace: close_pdeo+0x37/0xd0 proc_reg_release+0x5d/0x60 __fput+0x9d/0x1d0 ____fput+0x9/0x10 task_work_run+0x75/0x90 do_exit+0x252/0xa00 do_group_exit+0x36/0xb0 SyS_exit_group+0xf/0x10 Fixes: 516fb7f2e73d ("/proc/module: use the same logic as /proc/kallsyms for address exposure") Cc: Jessica Yu <jeyu@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: stable@vger.kernel.org # 4.15+ Signed-off-by: Leon Yu <chianglungyu@gmail.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-02-07Merge tag 'modules-for-v4.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: "Minor code cleanups and MAINTAINERS update" * tag 'modules-for-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: modpost: Remove trailing semicolon ftrace/module: Move ftrace_release_mod() to ddebug_cleanup label MAINTAINERS: Remove from module & paravirt maintenance
2018-02-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk updates from Petr Mladek: - Add a console_msg_format command line option: The value "default" keeps the old "[time stamp] text\n" format. The value "syslog" allows to see the syslog-like "<log level>[timestamp] text" format. This feature was requested by people doing regression tests, for example, 0day robot. They want to have both filtered and full logs at hands. - Reduce the risk of softlockup: Pass the console owner in a busy loop. This is a new approach to the old problem. It was first proposed by Steven Rostedt on Kernel Summit 2017. It marks a context in which the console_lock owner calls console drivers and could not sleep. On the other side, printk() callers could detect this state and use a busy wait instead of a simple console_trylock(). Finally, the console_lock owner checks if there is a busy waiter at the end of the special context and eventually passes the console_lock to the waiter. The hand-off works surprisingly well and helps in many situations. Well, there is still a possibility of the softlockup, for example, when the flood of messages stops and the last owner still has too much to flush. There is increasing number of people having problems with printk-related softlockups. We might eventually need to get better solution. Anyway, this looks like a good start and promising direction. - Do not allow to schedule in console_unlock() called from printk(): This reverts an older controversial commit. The reschedule helped to avoid softlockups. But it also slowed down the console output. This patch is obsoleted by the new console waiter logic described above. In fact, the reschedule made the hand-off less effective. - Deprecate "%pf" and "%pF" format specifier: It was needed on ia64, ppc64 and parisc64 to dereference function descriptors and show the real function address. It is done transparently by "%ps" and "pS" format specifier now. Sergey Senozhatsky found that all the function descriptors were in a special elf section and could be easily detected. - Remove printk_symbol() API: It has been obsoleted by "%pS" format specifier, and this change helped to remove few continuous lines and a less intuitive old API. - Remove redundant memsets: Sergey removed unnecessary memset when processing printk.devkmsg command line option. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (27 commits) printk: drop redundant devkmsg_log_str memsets printk: Never set console_may_schedule in console_trylock() printk: Hide console waiter logic into helpers printk: Add console owner and waiter logic to load balance console writes kallsyms: remove print_symbol() function checkpatch: add pF/pf deprecation warning symbol lookup: introduce dereference_symbol_descriptor() parisc64: Add .opd based function descriptor dereference powerpc64: Add .opd based function descriptor dereference ia64: Add .opd based function descriptor dereference sections: split dereference_function_descriptor() openrisc: Fix conflicting types for _exext and _stext lib: do not use print_symbol() irq debug: do not use print_symbol() sysfs: do not use print_symbol() drivers: do not use print_symbol() x86: do not use print_symbol() unicore32: do not use print_symbol() sh: do not use print_symbol() mn10300: do not use print_symbol() ...
2018-01-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Significantly shrink the core networking routing structures. Result of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf 2) Add netdevsim driver for testing various offloads, from Jakub Kicinski. 3) Support cross-chip FDB operations in DSA, from Vivien Didelot. 4) Add a 2nd listener hash table for TCP, similar to what was done for UDP. From Martin KaFai Lau. 5) Add eBPF based queue selection to tun, from Jason Wang. 6) Lockless qdisc support, from John Fastabend. 7) SCTP stream interleave support, from Xin Long. 8) Smoother TCP receive autotuning, from Eric Dumazet. 9) Lots of erspan tunneling enhancements, from William Tu. 10) Add true function call support to BPF, from Alexei Starovoitov. 11) Add explicit support for GRO HW offloading, from Michael Chan. 12) Support extack generation in more netlink subsystems. From Alexander Aring, Quentin Monnet, and Jakub Kicinski. 13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From Russell King. 14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso. 15) Many improvements and simplifications to the NFP driver bpf JIT, from Jakub Kicinski. 16) Support for ipv6 non-equal cost multipath routing, from Ido Schimmel. 17) Add resource abstration to devlink, from Arkadi Sharshevsky. 18) Packet scheduler classifier shared filter block support, from Jiri Pirko. 19) Avoid locking in act_csum, from Davide Caratti. 20) devinet_ioctl() simplifications from Al viro. 21) More TCP bpf improvements from Lawrence Brakmo. 22) Add support for onlink ipv6 route flag, similar to ipv4, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits) tls: Add support for encryption using async offload accelerator ip6mr: fix stale iterator net/sched: kconfig: Remove blank help texts openvswitch: meter: Use 64-bit arithmetic instead of 32-bit tcp_nv: fix potential integer overflow in tcpnv_acked r8169: fix RTL8168EP take too long to complete driver initialization. qmi_wwan: Add support for Quectel EP06 rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK ipmr: Fix ptrdiff_t print formatting ibmvnic: Wait for device response when changing MAC qlcnic: fix deadlock bug tcp: release sk_frag.page in tcp_disconnect ipv4: Get the address of interface correctly. net_sched: gen_estimator: fix lockdep splat net: macb: Handle HRESP error net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring ipv6: addrconf: break critical section in addrconf_verify_rtnl() ipv6: change route cache aging logic i40e/i40evf: Update DESC_NEEDED value to reflect larger value bnxt_en: cleanup DIM work on device shutdown ...
2018-01-29Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/pti updates from Thomas Gleixner: "Another set of melted spectrum related changes: - Code simplifications and cleanups for RSB and retpolines. - Make the indirect calls in KVM speculation safe. - Whitelist CPUs which are known not to speculate from Meltdown and prepare for the new CPUID flag which tells the kernel that a CPU is not affected. - A less rigorous variant of the module retpoline check which merily warns when a non-retpoline protected module is loaded and reflects that fact in the sysfs file. - Prepare for Indirect Branch Prediction Barrier support. - Prepare for exposure of the Speculation Control MSRs to guests, so guest OSes which depend on those "features" can use them. Includes a blacklist of the broken microcodes. The actual exposure of the MSRs through KVM is still being worked on" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/speculation: Simplify indirect_branch_prediction_barrier() x86/retpoline: Simplify vmexit_fill_RSB() x86/cpufeatures: Clean up Spectre v2 related CPUID flags x86/cpu/bugs: Make retpoline module warning conditional x86/bugs: Drop one "mitigation" from dmesg x86/nospec: Fix header guards names x86/alternative: Print unadorned pointers x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown x86/msr: Add definitions for new speculation control MSRs x86/cpufeatures: Add AMD feature bits for Speculation Control x86/cpufeatures: Add Intel feature bits for Speculation Control x86/cpufeatures: Add CPUID_7_EDX CPUID leaf module/retpoline: Warn about missing retpoline in module KVM: VMX: Make indirect call speculation safe KVM: x86: Make indirect calls in emulator speculation safe
2018-01-26module/retpoline: Warn about missing retpoline in moduleAndi Kleen
There's a risk that a kernel which has full retpoline mitigations becomes vulnerable when a module gets loaded that hasn't been compiled with the right compiler or the right option. To enable detection of that mismatch at module load time, add a module info string "retpoline" at build time when the module was compiled with retpoline support. This only covers compiled C source, but assembler source or prebuilt object files are not checked. If a retpoline enabled kernel detects a non retpoline protected module at load time, print a warning and report it in the sysfs vulnerability file. [ tglx: Massaged changelog ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: gregkh@linuxfoundation.org Cc: torvalds@linux-foundation.org Cc: jeyu@kernel.org Cc: arjan@linux.intel.com Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
2018-01-15ftrace/module: Move ftrace_release_mod() to ddebug_cleanup labelNamit Gupta
ftrace_module_init happen after dynamic_debug_setup, it is desired that cleanup should be called after this label however in current implementation it is called in free module label,ie:even though ftrace in not initialized, from so many fail case ftrace_release_mod() will be called and unnecessary traverse the whole list. In below patch we moved ftrace_release_mod() from free_module label to ddebug_cleanup label. that is the best possible location, other solution is to make new label to ftrace_release_mod() but since ftrace_module_init() is not return with minimum changes it should be in ddebug_cleanup label. Signed-off-by: Namit Gupta <gupta.namit@samsung.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2018-01-12error-injection: Separate error-injection from kprobeMasami Hiramatsu
Since error-injection framework is not limited to be used by kprobes, nor bpf. Other kernel subsystems can use it freely for checking safeness of error-injection, e.g. livepatch, ftrace etc. So this separate error-injection framework from kprobes. Some differences has been made: - "kprobe" word is removed from any APIs/structures. - BPF_ALLOW_ERROR_INJECTION() is renamed to ALLOW_ERROR_INJECTION() since it is not limited for BPF too. - CONFIG_FUNCTION_ERROR_INJECTION is the config item of this feature. It is automatically enabled if the arch supports error injection feature for kprobe or ftrace etc. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-09sections: split dereference_function_descriptor()Sergey Senozhatsky
There are two format specifiers to print out a pointer in symbolic format: '%pS/%ps' and '%pF/%pf'. On most architectures, the two mean exactly the same thing, but some architectures (ia64, ppc64, parisc64) use an indirect pointer for C function pointers, where the function pointer points to a function descriptor (which in turn contains the actual pointer to the code). The '%pF/%pf, when used appropriately, automatically does the appropriate function descriptor dereference on such architectures. The "when used appropriately" part is tricky. Basically this is a subtle ABI detail, specific to some platforms, that made it to the API level and people can be unaware of it and miss the whole "we need to dereference the function" business out. [1] proves that point (note that it fixes only '%pF' and '%pS', there might be '%pf' and '%ps' cases as well). It appears that we can handle everything within the affected arches and make '%pS/%ps' smart enough to retire '%pF/%pf'. Function descriptors live in .opd elf section and all affected arches (ia64, ppc64, parisc64) handle it properly for kernel and modules. So we, technically, can decide if the dereference is needed by simply looking at the pointer: if it belongs to .opd section then we need to dereference it. The kernel and modules have their own .opd sections, obviously, that's why we need to split dereference_function_descriptor() and use separate kernel and module dereference arch callbacks. This patch does the first step, it a) adds dereference_kernel_function_descriptor() function. b) adds a weak alias to dereference_module_function_descriptor() function. So, for the time being, we will have: 1) dereference_function_descriptor() A generic function, that simply dereferences the pointer. There is bunch of places that call it: kgdbts, init/main.c, extable, etc. 2) dereference_kernel_function_descriptor() A function to call on kernel symbols that does kernel .opd section address range test. 3) dereference_module_function_descriptor() A function to call on modules' symbols that does modules' .opd section address range test. [1] https://marc.info/?l=linux-kernel&m=150472969730573 Link: http://lkml.kernel.org/r/20171109234830.5067-2-sergey.senozhatsky@gmail.com To: Fenghua Yu <fenghua.yu@intel.com> To: Benjamin Herrenschmidt <benh@kernel.crashing.org> To: Paul Mackerras <paulus@samba.org> To: Michael Ellerman <mpe@ellerman.id.au> To: James Bottomley <jejb@parisc-linux.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-ia64@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Tested-by: Tony Luck <tony.luck@intel.com> #ia64 Tested-by: Santosh Sivaraj <santosh@fossix.org> #powerpc Tested-by: Helge Deller <deller@gmx.de> #parisc64 Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-12-12add infrastructure for tagging functions as error injectableJosef Bacik
Using BPF we can override kprob'ed functions and return arbitrary values. Obviously this can be a bit unsafe, so make this feature opt-in for functions. Simply tag a function with KPROBE_ERROR_INJECT_SYMBOL in order to give BPF access to that function for error injection purposes. Signed-off-by: Josef Bacik <jbacik@fb.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-11-29kallsyms: take advantage of the new '%px' formatLinus Torvalds
The conditional kallsym hex printing used a special fixed-width '%lx' output (KALLSYM_FMT) in preparation for the hashing of %p, but that series ended up adding a %px specifier to help with the conversions. Use it, and avoid the "print pointer as an unsigned long" code. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17Merge tag 'trace-v4.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from - allow module init functions to be traced - clean up some unused or not used by config events (saves space) - clean up of trace histogram code - add support for preempt and interrupt enabled/disable events - other various clean ups * tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits) tracing, thermal: Hide cpu cooling trace events when not in use tracing, thermal: Hide devfreq trace events when not in use ftrace: Kill FTRACE_OPS_FL_PER_CPU perf/ftrace: Small cleanup perf/ftrace: Fix function trace events perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function") tracing, dma-buf: Remove unused trace event dma_fence_annotate_wait_on tracing, memcg, vmscan: Hide trace events when not in use tracing/xen: Hide events that are not used when X86_PAE is not defined tracing: mark trace_test_buffer as __maybe_unused printk: Remove superfluous memory barriers from printk_safe ftrace: Clear hashes of stale ips of init memory tracing: Add support for preempt and irq enable/disable events tracing: Prepare to add preempt and irq trace events ftrace/kallsyms: Have /proc/kallsyms show saved mod init functions ftrace: Add freeing algorithm to free ftrace_mod_maps ftrace: Save module init functions kallsyms symbols for tracing ftrace: Allow module init functions to be traced ftrace: Add a ftrace_free_mem() function for modules to use tracing: Reimplement log2 ...