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2019-04-30clocksource/arm_arch_timer: Remove use of workaround static keyMarc Zyngier
The use of a static key in a hotplug path has proved to be a real nightmare, and makes it impossible to have scream-free lockdep kernel. Let's remove the static key altogether, and focus on something saner. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stableMarc Zyngier
Let's start with the removal of the arch_timer_read_ool_enabled static key in arch_timer_reg_read_stable. It is not a fast path, and we can simplify things a bit. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30clocksource/arm_arch_timer: Direcly assign set_next_event workaroundMarc Zyngier
When a given timer is affected by an erratum and requires an alternative implementation of set_next_event, we do a rather complicated dance to detect and call the workaround on each set_next_event call. This is clearly idiotic, as we can perfectly detect whether this CPU requires a workaround while setting up the clock event device. This only requires the CPU-specific detection to be done a bit earlier, and we can then safely override the set_next_event pointer if we have a workaround associated to that CPU. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by; Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvctMarc Zyngier
Only arch_timer_read_counter will guarantee that workarounds are applied. So let's use this one instead of arch_counter_get_cntvct. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30appletalk: Set error code if register_snap_client failedYueHaibing
If register_snap_client fails in atalk_init, error code should be set, otherwise it will triggers NULL pointer dereference while unloading module. Fixes: 9804501fa122 ("appletalk: Fix potential NULL pointer dereference in unregister_snap_client") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-30watchdog/sbsa: Use arch_timer_read_counter instead of arch_counter_get_cntvctMarc Zyngier
Only arch_timer_read_counter will guarantee that workarounds are applied. So let's use this one instead of arch_counter_get_cntvct. Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30ARM: vdso: Remove dependency with the arch_timer driver internalsMarc Zyngier
The VDSO code uses the kernel helper that was originally designed to abstract the access between 32 and 64bit systems. It worked so far because this function is declared as 'inline'. As we're about to revamp that part of the code, the VDSO would break. Let's fix it by doing what should have been done from the start, a proper system register access. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30net: dsa: bcm_sf2: fix buffer overflow doing set_rxnfcDan Carpenter
The "fs->location" is a u32 that comes from the user in ethtool_set_rxnfc(). We can't pass unclamped values to test_bit() or it results in an out of bounds access beyond the end of the bitmap. Fixes: 7318166cacad ("net: dsa: bcm_sf2: Add support for ethtool::rxnfc") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-30rxrpc: Fix net namespace cleanupDavid Howells
In rxrpc_destroy_all_calls(), there are two phases: (1) make sure the ->calls list is empty, emitting error messages if not, and (2) wait for the RCU cleanup to happen on outstanding calls (ie. ->nr_calls becomes 0). To avoid taking the call_lock, the function prechecks ->calls and if empty, it returns to avoid taking the lock - this is wrong, however: it still needs to go and do the second phase and wait for ->nr_calls to become 0. Without this, the rxrpc_net struct may get deallocated before we get to the RCU cleanup for the last calls. This can lead to: Slab corruption (Not tainted): kmalloc-16k start=ffff88802b178000, len=16384 050: 6b 6b 6b 6b 6b 6b 6b 6b 61 6b 6b 6b 6b 6b 6b 6b kkkkkkkkakkkkkkk Note the "61" at offset 0x58. This corresponds to the ->nr_calls member of struct rxrpc_net (which is >9k in size, and thus allocated out of the 16k slab). Fix this by flipping the condition on the if-statement, putting the locked section inside the if-body and dropping the return from there. The function will then always go on to wait for the RCU cleanup on outstanding calls. Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-30arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1Marc Zyngier
Neoverse-N1 is also affected by ARM64_ERRATUM_1188873, so let's add it to the list of affected CPUs. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> [will: Update silicon-errata.txt] Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30arm64: Add part number for Neoverse N1Marc Zyngier
New CPU, new part number. You know the drill. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30arm64: Make ARM64_ERRATUM_1188873 depend on COMPATMarc Zyngier
Since ARM64_ERRATUM_1188873 only affects AArch32 EL0, it makes some sense that it should depend on COMPAT. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32Marc Zyngier
We currently deal with ARM64_ERRATUM_1188873 by always trapping EL0 accesses for both instruction sets. Although nothing wrong comes out of that, people trying to squeeze the last drop of performance from buggy HW find this over the top. Oh well. Let's change the mitigation by flipping the counter enable bit on return to userspace. Non-broken HW gets an extra branch on the fast path, which is hopefully not the end of the world. The arch timer workaround is also removed. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30HID: logitech-dj: fix spelling in printkColin Ian King
There is a spelling mistake in a hid_err error message, fix it. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2019-04-30ALSA: hda/realtek - Apply the fixup for ASUS Q325UARTakashi Iwai
Some ASUS models like Q325UAR with ALC295 codec requires the same fixup that has been applied to ALC294 codec. Just copy the entry with the pin matching to cover ALC295 too. BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1784485 Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-04-30Merge branch 'master' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2019-04-30 1) Fix an out-of-bound array accesses in __xfrm_policy_unlink. From YueHaibing. 2) Reset the secpath on failure in the ESP GRO handlers to avoid dereferencing an invalid pointer on error. From Myungho Jung. 3) Add and revert a patch that tried to add rcu annotations to netns_xfrm. From Su Yanjun. 4) Wait for rcu callbacks before freeing xfrm6_tunnel_spi_kmem. From Su Yanjun. 5) Fix forgotten vti4 ipip tunnel deregistration. From Jeremy Sowden: 6) Remove some duplicated log messages in vti4. From Jeremy Sowden. 7) Don't use IPSEC_PROTO_ANY when flushing states because this will flush only IPsec portocol speciffic states. IPPROTO_ROUTING states may remain in the lists when doing net exit. Fix this by replacing IPSEC_PROTO_ANY with zero. From Cong Wang. 8) Add length check for UDP encapsulation to fix "Oversized IP packet" warnings on receive side. From Sabrina Dubroca. 9) Fix xfrm interface lookup when the interface is associated to a vrf layer 3 master device. From Martin Willi. 10) Reload header pointers after pskb_may_pull() in _decode_session4(), otherwise we may read from uninitialized memory. 11) Update the documentation about xfrm[46]_gc_thresh, it is not used anymore after the flowcache removal. From Nicolas Dichtel. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-30Revert "drm/qxl: drop prime import/export callbacks"Gerd Hoffmann
This reverts commit f4c34b1e2a37d5676180901fa6ff188bcb6371f8. Simliar to commit a0cecc23cfcb Revert "drm/virtio: drop prime import/export callbacks". We have to do the same with qxl, for the same reasons (it breaks DRI3). Drop the WARN_ON_ONCE(). Fixes: f4c34b1e2a37d5676 ("drm/qxl: drop prime import/export callbacks") Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Link: http://patchwork.freedesktop.org/patch/msgid/20190426053324.26443-1-kraxel@redhat.com Acked-by: Daniel Vetter <daniel@ffwll.ch>
2019-04-30arm64: mm: Remove pte_unmap_nested()Qian Cai
As of commit ece0e2b6406a ("mm: remove pte_*map_nested()"), pte_unmap_nested() is no longer used and can be removed from the arm64 code. Signed-off-by: Qian Cai <cai@lca.pw> [will: also remove pte_offset_map_nested()] Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variableQian Cai
When building with -Wunused-but-set-variable, the compiler shouts about a number of pte_unmap() users, since this expands to an empty macro on arm64: | mm/gup.c: In function 'gup_pte_range': | mm/gup.c:1727:16: warning: variable 'ptem' set but not used | [-Wunused-but-set-variable] | mm/gup.c: At top level: | mm/memory.c: In function 'copy_pte_range': | mm/memory.c:821:24: warning: variable 'orig_dst_pte' set but not used | [-Wunused-but-set-variable] | mm/memory.c:821:9: warning: variable 'orig_src_pte' set but not used | [-Wunused-but-set-variable] | mm/swap_state.c: In function 'swap_ra_info': | mm/swap_state.c:641:15: warning: variable 'orig_pte' set but not used | [-Wunused-but-set-variable] | mm/madvise.c: In function 'madvise_free_pte_range': | mm/madvise.c:318:9: warning: variable 'orig_pte' set but not used | [-Wunused-but-set-variable] Rewrite pte_unmap() as a static inline function, which silences the warnings. Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30x86/alternatives: Add comment about module removal racesNadav Amit
Add a comment to clarify that users of text_poke() must ensure that no races with module removal take place. 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@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-22-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/kprobes: Use vmalloc special flagRick Edgecombe
Use new flag VM_FLUSH_RESET_PERMS for handling freeing of special permissioned memory in vmalloc and remove places where memory was set NX and RW before freeing which is no longer needed. 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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-21-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/ftrace: Use vmalloc special flagRick Edgecombe
Use new flag VM_FLUSH_RESET_PERMS for handling freeing of special permissioned memory in vmalloc and remove places where memory was set NX and RW before freeing which is no longer needed. Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-20-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30bpf: Use vmalloc special flagRick Edgecombe
Use new flag VM_FLUSH_RESET_PERMS for handling freeing of special permissioned memory in vmalloc and remove places where memory was set RW before freeing which is no longer needed. Don't track if the memory is RO anymore because it is now tracked in vmalloc. 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: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-19-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
2019-04-30mm/vmalloc: Add flag for freeing of special permsissionsRick Edgecombe
Add a new flag VM_FLUSH_RESET_PERMS, for enabling vfree operations to immediately clear executable TLB entries before freeing pages, and handle resetting permissions on the directmap. This flag is useful for any kind of memory with elevated permissions, or where there can be related permissions changes on the directmap. Today this is RO+X and RO memory. Although this enables directly vfreeing non-writeable memory now, non-writable memory cannot be freed in an interrupt because the allocation itself is used as a node on deferred free list. So when RO memory needs to be freed in an interrupt the code doing the vfree needs to have its own work queue, as was the case before the deferred vfree list was added to vmalloc. For architectures with set_direct_map_ implementations this whole operation can be done with one TLB flush when centralized like this. For others with directmap permissions, currently only arm64, a backup method using set_memory functions is used to reset the directmap. When arm64 adds set_direct_map_ functions, this backup can be removed. When the TLB is flushed to both remove TLB entries for the vmalloc range mapping and the direct map permissions, the lazy purge operation could be done to try to save a TLB flush later. However today vm_unmap_aliases could flush a TLB range that does not include the directmap. So a helper is added with extra parameters that can allow both the vmalloc address and the direct mapping to be flushed during this operation. The behavior of the normal vm_unmap_aliases function is unchanged. Suggested-by: Dave Hansen <dave.hansen@intel.com> Suggested-by: Andy Lutomirski <luto@kernel.org> Suggested-by: Will Deacon <will.deacon@arm.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: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-17-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30mm/hibernation: Make hibernation handle unmapped pagesRick Edgecombe
Make hibernate handle unmapped pages on the direct map when CONFIG_ARCH_HAS_SET_ALIAS=y is set. These functions allow for setting pages to invalid configurations, so now hibernate should check if the pages have valid mappings and handle if they are unmapped when doing a hibernate save operation. Previously this checking was already done when CONFIG_DEBUG_PAGEALLOC=y was configured. It does not appear to have a big hibernating performance impact. The speed of the saving operation before this change was measured as 819.02 MB/s, and after was measured at 813.32 MB/s. Before: [ 4.670938] PM: Wrote 171996 kbytes in 0.21 seconds (819.02 MB/s) After: [ 4.504714] PM: Wrote 178932 kbytes in 0.22 seconds (813.32 MB/s) Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Pavel Machek <pavel@ucw.cz> 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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-16-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/mm/cpa: Add set_direct_map_*() functionsRick Edgecombe
Add two new functions set_direct_map_default_noflush() and set_direct_map_invalid_noflush() for setting the direct map alias for the page to its default valid permissions and to an invalid state that cannot be cached in a TLB, respectively. These functions do not flush the TLB. Note, __kernel_map_pages() does something similar but flushes the TLB and doesn't reset the permission bits to default on all architectures. Also add an ARCH config ARCH_HAS_SET_DIRECT_MAP for specifying whether these have an actual implementation or a default empty one. 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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-15-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/alternatives: Remove the return value of text_poke_*()Nadav Amit
The return value of text_poke_early() and text_poke_bp() is useless. Remove it. 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: 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> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-14-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/jump-label: Remove support for custom text pokerNadav Amit
There are only two types of text poking: early and breakpoint based. The use of a function pointer to perform text poking complicates the code and is probably inefficient due to the use of indirect branches. 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: 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> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-13-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>
2019-04-30x86/kprobes: Set instruction page as executableNadav Amit
Set the page as executable after allocation. This patch is a preparatory patch for a following patch that makes module allocated pages non-executable. While at it, do some small cleanup of what appears to be unnecessary masking. 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@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-11-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/ftrace: Set trampoline pages as executableNadav Amit
Since alloc_module() will not set the pages as executable soon, set ftrace trampoline pages as executable after they are allocated. For the time being, do not change ftrace to use the text_poke() interface. As a result, ftrace still breaks W^X. 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> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-10-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/kgdb: Avoid redundant comparison of patched codeNadav Amit
text_poke() already ensures that the written value is the correct one and fails if that is not the case. There is no need for an additional comparison. Remove it. 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@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-9-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/alternatives: Use temporary mm for text pokingNadav Amit
text_poke() can potentially compromise security as it sets temporary PTEs in the fixmap. These PTEs might be used to rewrite the kernel code from other cores accidentally or maliciously, if an attacker gains the ability to write onto kernel memory. Moreover, since remote TLBs are not flushed after the temporary PTEs are removed, the time-window in which the code is writable is not limited if the fixmap PTEs - maliciously or accidentally - are cached in the TLB. To address these potential security hazards, use a temporary mm for patching the code. Finally, text_poke() is also not conservative enough when mapping pages, as it always tries to map 2 pages, even when a single one is sufficient. So try to be more conservative, and do not map more than needed. 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: 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> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-8-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/alternatives: Initialize temporary mm for patchingNadav Amit
To prevent improper use of the PTEs that are used for text patching, the next patches will use a temporary mm struct. Initailize it by copying the init mm. The address that will be used for patching is taken from the lower area that is usually used for the task memory. Doing so prevents the need to frequently synchronize the temporary-mm (e.g., when BPF programs are installed), since different PGDs are used for the task memory. Finally, randomize the address of the PTEs to harden against exploits that use these PTEs. Suggested-by: Andy Lutomirski <luto@kernel.org> Tested-by: Masami Hiramatsu <mhiramat@kernel.org> 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> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> 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 Link: https://lkml.kernel.org/r/20190426232303.28381-8-nadav.amit@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30fork: Provide a function for copying init_mmNadav Amit
Provide a function for copying init_mm. This function will be later used for setting a temporary mm. Tested-by: Masami Hiramatsu <mhiramat@kernel.org> 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> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.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: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-6-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30uprobes: Initialize uprobes earlierNadav Amit
In order to have a separate address space for text poking, we need to duplicate init_mm early during start_kernel(). This, however, introduces a problem since uprobes functions are called from dup_mmap(), but uprobes is still not initialized in this early stage. Since uprobes initialization is necassary for fork, and since all the dependant initialization has been done when fork is initialized (percpu and vmalloc), move uprobes initialization to fork_init(). It does not seem uprobes introduces any security problem for the poking_mm. Crash and burn if uprobes initialization fails, similarly to other early initializations. Change the init_probes() name to probes_init() to match other early initialization functions name convention. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> 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 Link: https://lkml.kernel.org/r/20190426232303.28381-6-nadav.amit@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/mm: Save debug registers when loading a temporary mmNadav Amit
Prevent user watchpoints from mistakenly firing while the temporary mm is being used. As the addresses of the temporary mm might overlap those of the user-process, this is necessary to prevent wrong signals or worse things from happening. 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@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-5-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/mm: Introduce temporary mm structsAndy Lutomirski
Using a dedicated page-table for temporary PTEs prevents other cores from using - even speculatively - these PTEs, thereby providing two benefits: (1) Security hardening: an attacker that gains kernel memory writing abilities cannot easily overwrite sensitive data. (2) Avoiding TLB shootdowns: the PTEs do not need to be flushed in remote page-tables. To do so a temporary mm_struct can be used. Mappings which are private for this mm can be set in the userspace part of the address-space. During the whole time in which the temporary mm is loaded, interrupts must be disabled. The first use-case for temporary mm struct, which will follow, is for poking the kernel text. [ Commit message was written by Nadav Amit ] Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Andy Lutomirski <luto@kernel.org> 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> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.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: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-4-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/jump_label: Use text_poke_early() during early initNadav Amit
There is no apparent reason not to use text_poke_early() during early-init, since no patching of code that might be on the stack is done and only a single core is running. This is required for the next patches that would set a temporary mm for text poking, and this mm is only initialized after some static-keys are enabled/disabled. 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: 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> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-3-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30bpf: Fail bpf_probe_write_user() while mm is switchedNadav Amit
When using a temporary mm, bpf_probe_write_user() should not be able to write to user memory, since user memory addresses may be used to map kernel memory. Detect these cases and fail bpf_probe_write_user() in such cases. Suggested-by: Jann Horn <jannh@google.com> Reported-by: Jann Horn <jannh@google.com> 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: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-24-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30mm/tlb: Provide default nmi_uaccess_okay()Nadav Amit
x86 has an nmi_uaccess_okay(), but other architectures do not. Arch-independent code might need to know whether access to user addresses is ok in an NMI context or in other code whose execution context is unknown. Specifically, this function is needed for bpf_probe_write_user(). Add a default implementation of nmi_uaccess_okay() for architectures that do not have such a function. 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@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190426001143.4983-23-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30x86/alternatives: Add text_poke_kgdb() to not assert the lock when debuggingNadav Amit
text_mutex is currently expected to be held before text_poke() is called, but kgdb does not take the mutex, and instead *supposedly* ensures the lock is not taken and will not be acquired by any other core while text_poke() is running. The reason for the "supposedly" comment is that it is not entirely clear that this would be the case if gdb_do_roundup is zero. Create two wrapper functions, text_poke() and text_poke_kgdb(), which do or do not run the lockdep assertion respectively. While we are at it, change the return code of text_poke() to something meaningful. One day, callers might actually respect it and the existing BUG_ON() when patching fails could be removed. For kgdb, the return value can actually be used. Suggested-by: Peter Zijlstra <peterz@infradead.org> 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> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Jiri Kosina <jkosina@suse.cz> 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: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 9222f606506c ("x86/alternatives: Lockdep-enforce text_mutex in text_poke*()") Link: https://lkml.kernel.org/r/20190426001143.4983-2-namit@vmware.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30arm64: compat: Reduce address limit for 64K pagesVincenzo Frascino
With the introduction of the config option that allows to enable kuser helpers, it is now possible to reduce TASK_SIZE_32 when these are disabled and 64K pages are enabled. This extends the compliance with the section 6.5.8 of the C standard (C99). Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30arm64: arch_timer: Ensure counter register reads occur with seqlock heldWill Deacon
When executing clock_gettime(), either in the vDSO or via a system call, we need to ensure that the read of the counter register occurs within the seqlock reader critical section. This ensures that updates to the clocksource parameters (e.g. the multiplier) are consistent with the counter value and therefore avoids the situation where time appears to go backwards across multiple reads. Extend the vDSO logic so that the seqlock critical section covers the read of the counter register as well as accesses to the data page. Since reads of the counter system registers are not ordered by memory barrier instructions, introduce dependency ordering from the counter read to a subsequent memory access so that the seqlock memory barriers apply to the counter access in both the vDSO and the system call paths. Cc: <stable@vger.kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/linux-arm-kernel/alpine.DEB.2.21.1902081950260.1662@nanos.tec.linutronix.de/ Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30cpufreq: Fix kobject memleakViresh Kumar
Currently the error return path from kobject_init_and_add() is not followed by a call to kobject_put() - which means we are leaking the kobject. Fix it by adding a call to kobject_put() in the error path of kobject_init_and_add(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Tobin C. Harding <tobin@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-30Merge branch 'cpufreq/arm/linux-next' of ↵Rafael J. Wysocki
git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm into pm-cpufreq Pull ARM cpufreq drivers changes for v5.2 from Viresh Kumar: "This pull request contains: - Fix for possible object reference leak for few drivers (Wen Yang). - Fix for armada frequency calculation (Gregory). - Code cleanup in maple driver (Viresh). This contains some non-ARM bits as well this time as the patches were picked up from a series." * 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: cpufreq: armada-37xx: fix frequency calculation for opp cpufreq: maple: Remove redundant code from maple_cpufreq_init() cpufreq: ppc_cbe: fix possible object reference leak cpufreq: pmac32: fix possible object reference leak cpufreq/pasemi: fix possible object reference leak cpufreq: maple: fix possible object reference leak cpufreq: kirkwood: fix possible object reference leak cpufreq: imx6q: fix possible object reference leak cpufreq: ap806: fix possible object reference leak
2019-04-30Merge branch 'opp/linux-next' of ↵Rafael J. Wysocki
git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm into pm-opp Pull operating performance points (OPP) framework changes for v5.2 from Viresh Kumar: "This pull request contains: - New helper in OPP core to find best matching frequency for a voltage value." * 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: OPP: Introduce dev_pm_opp_find_freq_ceil_by_volt()
2019-04-30sched/cpufreq: Fix kobject memleakTobin C. Harding
Currently the error return path from kobject_init_and_add() is not followed by a call to kobject_put() - which means we are leaking the kobject. Fix it by adding a call to kobject_put() in the error path of kobject_init_and_add(). Signed-off-by: Tobin C. Harding <tobin@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tobin C. Harding <tobin@kernel.org> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Link: http://lkml.kernel.org/r/20190430001144.24890-1-tobin@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30Merge tag 'v5.1-rc7' into x86/mm, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>