- 09 Jun, 2017 23 commits
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Mark Rutland authored
If a key's refcount is dropped to zero between key_lookup() peeking at the refcount and subsequently attempting to increment it, refcount_inc() will see a zero refcount. Here, refcount_inc() will WARN_ONCE(), and will *not* increment the refcount, which will remain zero. Once key_lookup() drops key_serial_lock, it is possible for the key to be freed behind our back. This patch uses refcount_inc_not_zero() to perform the peek and increment atomically. Fixes: fff29291 ("security, keys: convert key.usage from atomic_t to refcount_t") Signed-off-by:
Mark Rutland <mark.rutland@arm.com> Signed-off-by:
David Howells <dhowells@redhat.com> Cc: David Windsor <dwindsor@gmail.com> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Hans Liljestrand <ishkamiel@gmail.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by:
James Morris <james.l.morris@oracle.com>
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Mat Martineau authored
The initial Diffie-Hellman computation made direct use of the MPI library because the crypto module did not support DH at the time. Now that KPP is implemented, KEYCTL_DH_COMPUTE should use it to get rid of duplicate code and leverage possible hardware acceleration. This fixes an issue whereby the input to the KDF computation would include additional uninitialized memory when the result of the Diffie-Hellman computation was shorter than the input prime number. Signed-off-by:
Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by:
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Loganaden Velvindron authored
Signed-off-by:
Loganaden Velvindron <logan@hackers.mu> Signed-off-by:
Yasir Auleear <yasirmx@hackers.mu> Signed-off-by:
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Eric Biggers authored
Signed-off-by:
Eric Biggers <ebiggers@google.com> Signed-off-by:
Stephan Mueller <smueller@chronox.de> Signed-off-by:
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Eric Biggers authored
Accessing a 'u8[4]' through a '__be32 *' violates alignment rules. Just make the counter a __be32 instead. Signed-off-by:
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Eric Biggers authored
If userspace called KEYCTL_DH_COMPUTE with kdf_params containing NULL otherinfo but nonzero otherinfolen, the kernel would allocate a buffer for the otherinfo, then feed it into the KDF without initializing it. Fix this by always doing the copy from userspace (which will fail with EFAULT in this scenario). Signed-off-by:
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Eric Biggers authored
Requesting "digest_null" in the keyctl_kdf_params caused an infinite loop in kdf_ctr() because the "null" hash has a digest size of 0. Fix it by rejecting hash algorithms with a digest size of 0. Signed-off-by:
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Eric Biggers authored
While a 'struct key' itself normally does not contain sensitive information, Documentation/security/keys.txt actually encourages this: "Having a payload is not required; and the payload can, in fact, just be a value stored in the struct key itself." In case someone has taken this advice, or will take this advice in the future, zero the key structure before freeing it. We might as well, and as a bonus this could make it a bit more difficult for an adversary to determine which keys have recently been in use. This is safe because the key_jar cache does not use a constructor. Signed-off-by: -
Eric Biggers authored
As the previous patch did for encrypted-keys, zero sensitive any potentially sensitive data related to the "trusted" key type before it is freed. Notably, we were not zeroing the tpm_buf structures in which the actual key is stored for TPM seal and unseal, nor were we zeroing the trusted_key_payload in certain error paths. Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: David Safford <safford@us.ibm.com> Signed-off-by:
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Eric Biggers authored
For keys of type "encrypted", consistently zero sensitive key material before freeing it. This was already being done for the decrypted payloads of encrypted keys, but not for the master key and the keys derived from the master key. Out of an abundance of caution and because it is trivial to do so, also zero buffers containing the key payload in encrypted form, although depending on how the encrypted-keys feature is used such information does not necessarily need to be kept secret. Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: David Safford <safford@us.ibm.com> Signed-off-by:
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Eric Biggers authored
Zero the payloads of user and logon keys before freeing them. This prevents sensitive key material from being kept around in the slab caches after a key is released. Signed-off-by:
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Eric Biggers authored
Before returning from add_key() or one of the keyctl() commands that takes in a key payload, zero the temporary buffer that was allocated to hold the key payload copied from userspace. This may contain sensitive key material that should not be kept around in the slab caches. Signed-off-by:
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Eric Biggers authored
key_update() freed the key_preparsed_payload even if it was not initialized first. This would cause a crash if userspace called keyctl_update() on a key with type like "asymmetric" that has a ->preparse() method but not an ->update() method. Possibly it could even be triggered for other key types by racing with keyctl_setperm() to make the KEY_NEED_WRITE check fail (the permission was already checked, so normally it wouldn't fail there). Reproducer with key type "asymmetric", given a valid cert.der: keyctl new_session keyid=$(keyctl padd asymmetric desc @s < cert.der) keyctl setperm $keyid 0x3f000000 keyctl update $keyid data [ 150.686666] BUG: unable to handle kernel NULL pointer dereference at 0000000000000001 [ 150.687601] IP: asymmetric_key_free_kids+0x12/0x30 [ 150.688139] PGD 38a3d067 [ 150.688141] PUD 3b3de067 [ 150.688447] PMD 0 [ 150.688745] [ 150.689160] Oops: 0000 [#1] SMP [ 150.689455] Modules linked in: [ 150.689769] CPU: 1 PID: 2478 Comm: keyctl Not tainted 4.11.0-rc4-xfstests-00187-ga9f6b6b8 #742 [ 150.690916] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014 [ 150.692199] task: ffff88003b30c480 task.stack: ffffc90000350000 [ 150.692952] RIP: 0010:asymmetric_key_free_kids+0x12/0x30 [ 150.693556] RSP: 0018:ffffc90000353e58 EFLAGS: 00010202 [ 150.694142] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000004 [ 150.694845] RDX: ffffffff81ee3920 RSI: ffff88003d4b0700 RDI: 0000000000000001 [ 150.697569] RBP: ffffc90000353e60 R08: ffff88003d5d2140 R09: 0000000000000000 [ 150.702483] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 [ 150.707393] R13: 0000000000000004 R14: ffff880038a4d2d8 R15: 000000000040411f [ 150.709720] FS: 00007fcbcee35700(0000) GS:ffff88003fd00000(0000) knlGS:0000000000000000 [ 150.711504] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 150.712733] CR2: 0000000000000001 CR3: 0000000039eab000 CR4: 00000000003406e0 [ 150.714487] Call Trace: [ 150.714975] asymmetric_key_free_preparse+0x2f/0x40 [ 150.715907] key_update+0xf7/0x140 [ 150.716560] ? key_default_cmp+0x20/0x20 [ 150.717319] keyctl_update_key+0xb0/0xe0 [ 150.718066] SyS_keyctl+0x109/0x130 [ 150.718663] entry_SYSCALL_64_fastpath+0x1f/0xc2 [ 150.719440] RIP: 0033:0x7fcbce75ff19 [ 150.719926] RSP: 002b:00007ffd5d167088 EFLAGS: 00000206 ORIG_RAX: 00000000000000fa [ 150.720918] RAX: ffffffffffffffda RBX: 0000000000404d80 RCX: 00007fcbce75ff19 [ 150.721874] RDX: 00007ffd5d16785e RSI: 000000002866cd36 RDI: 0000000000000002 [ 150.722827] RBP: 0000000000000006 R08: 000000002866cd36 R09: 00007ffd5d16785e [ 150.723781] R10: 0000000000000004 R11: 0000000000000206 R12: 0000000000404d80 [ 150.724650] R13: 00007ffd5d16784d R14: 00007ffd5d167238 R15: 000000000040411f [ 150.725447] Code: 83 c4 08 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 85 ff 74 23 55 48 89 e5 53 48 89 fb <48> 8b 3f e8 06 21 c5 ff 48 8b 7b 08 e8 fd 20 c5 ff 48 89 df e8 [ 150.727489] RIP: asymmetric_key_free_kids+0x12/0x30 RSP: ffffc90000353e58 [ 150.728117] CR2: 0000000000000001 [ 150.728430] ---[ end trace f7f8fe1da2d5ae8d ]--- Fixes: 4d8c0250 ("KEYS: Call ->free_preparse() even after ->preparse() returns an error") Cc: stable@vger.kernel.org # 3.17+ Signed-off-by:
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Eric Biggers authored
sys_add_key() and the KEYCTL_UPDATE operation of sys_keyctl() allowed a NULL payload with nonzero length to be passed to the key type's ->preparse(), ->instantiate(), and/or ->update() methods. Various key types including asymmetric, cifs.idmap, cifs.spnego, and pkcs7_test did not handle this case, allowing an unprivileged user to trivially cause a NULL pointer dereference (kernel oops) if one of these key types was present. Fix it by doing the copy_from_user() when 'plen' is nonzero rather than when '_payload' is non-NULL, causing the syscall to fail with EFAULT as expected when an invalid buffer is specified. Cc: stable@vger.kernel.org # 2.6.10+ Signed-off-by:
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Eric Biggers authored
MACs should, in general, be compared using crypto_memneq() to prevent timing attacks. Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
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Eric Biggers authored
The encrypted-keys module was using a single global HMAC transform, which could be rekeyed by multiple threads concurrently operating on different keys, causing incorrect HMAC values to be calculated. Fix this by allocating a new HMAC transform whenever we need to calculate a HMAC. Also simplify things a bit by allocating the shash_desc's using SHASH_DESC_ON_STACK() for both the HMAC and unkeyed hashes. The following script reproduces the bug: keyctl new_session keyctl add user master "abcdefghijklmnop" @s for i in $(seq 2); do ( set -e for j in $(seq 1000); do keyid=$(keyctl add encrypted desc$i "new user:master 25" @s) datablob="$(keyctl pipe $keyid)" keyctl unlink $keyid > /dev/null keyid=$(keyctl add encrypted desc$i "load $datablob" @s) keyctl unlink $keyid > /dev/null done ) & done Output with bug: [ 439.691094] encrypted_key: bad hmac (-22) add_key: Invalid argument add_key: Invalid argument Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: -
Eric Biggers authored
With the 'encrypted' key type it was possible for userspace to provide a data blob ending with a master key description shorter than expected, e.g. 'keyctl add encrypted desc "new x" @s'. When validating such a master key description, validate_master_desc() could read beyond the end of the buffer. Fix this by using strncmp() instead of memcmp(). [Also clean up the code to deduplicate some logic.] Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by:
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Eric Biggers authored
Since v4.9, the crypto API cannot (normally) be used to encrypt/decrypt stack buffers because the stack may be virtually mapped. Fix this for the padding buffers in encrypted-keys by using ZERO_PAGE for the encryption padding and by allocating a temporary heap buffer for the decryption padding. Tested with CONFIG_DEBUG_SG=y: keyctl new_session keyctl add user master "abcdefghijklmnop" @s keyid=$(keyctl add encrypted desc "new user:master 25" @s) datablob="$(keyctl pipe $keyid)" keyctl unlink $keyid keyid=$(keyctl add encrypted desc "load $datablob" @s) datablob2="$(keyctl pipe $keyid)" [ "$datablob" = "$datablob2" ] && echo "Success!" Cc: Andy Lutomirski <luto@kernel.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # 4.9+ Signed-off-by:
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Eric Biggers authored
In join_session_keyring(), if install_session_keyring_to_cred() were to fail, we would leak the keyring reference, just like in the bug fixed by commit 23567fd0 ("KEYS: Fix keyring ref leak in join_session_keyring()"). Fortunately this cannot happen currently, but we really should be more careful. Do this by adding and using a new error label at which the keyring reference is dropped. Signed-off-by:
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Markus Elfring authored
Omit an extra message for a memory allocation failure in this function. This issue was detected by using the Coccinelle software. Link: http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdfSigned-off-by:
Markus Elfring <elfring@users.sourceforge.net> Signed-off-by:
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Dan Carpenter authored
We forgot to set the error code on this path so it could result in returning NULL which leads to a NULL dereference. Fixes: db6c43bd ("crypto: KEYS: convert public key and digsig asym to the akcipher api") Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
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Davidlohr Bueso authored
With the new standardized functions, we can replace all ACCESS_ONCE() calls across relevant security/keyrings/. ACCESS_ONCE() does not work reliably on non-scalar types. For example gcc 4.6 and 4.7 might remove the volatile tag for such accesses during the SRA (scalar replacement of aggregates) step: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 Update the new calls regardless of if it is a scalar type, this is cleaner than having three alternatives. Signed-off-by:
Davidlohr Bueso <dbueso@suse.de> Signed-off-by:
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Bilal Amarni authored
CONFIG_KEYS_COMPAT is defined in arch-specific Kconfigs and is missing for several 64-bit architectures : mips, parisc, tile. At the moment and for those architectures, calling in 32-bit userspace the keyctl syscall would return an ENOSYS error. This patch moves the CONFIG_KEYS_COMPAT option to security/keys/Kconfig, to make sure the compatibility wrapper is registered by default for any 64-bit architecture as long as it is configured with CONFIG_COMPAT. [DH: Modified to remove arm64 compat enablement also as requested by Eric Biggers] Signed-off-by:
Bilal Amarni <bilal.amarni@gmail.com> Signed-off-by:
Arnd Bergmann <arnd@arndb.de> cc: Eric Biggers <ebiggers3@gmail.com> Signed-off-by:
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- 08 Jun, 2017 5 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linuxLinus Torvalds authored
Pull module maintainer address change from Jessica Yu: "A single patch that advertises my email address change" * tag 'modules-for-v4.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: MAINTAINERS: update email address for Jessica Yu
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git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printkLinus Torvalds authored
Pull printk fix from Petr Mladek: "This reverts a fix added into 4.12-rc1. It caused the kernel log to be printed on another console when two consoles of the same type were defined, e.g. console=ttyS0 console=ttyS1. This configuration was never supported by kernel itself, but it started to make sense with systemd. In other words, the commit broke userspace" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: Revert "printk: fix double printing with earlycon"
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git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds authored
Pull crypto fixes from Herbert Xu: "This fixes a couple of places in the crypto code that were doing interruptible sleeps dangerously. They have been converted to use non-interruptible sleeps. This also fixes a bug in asymmetric_keys where it would trigger a use-after-free if a request returned EBUSY due to a full device queue" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: gcm - wait for crypto op not signal safe crypto: drbg - wait for crypto op not signal safe crypto: asymmetric_keys - handle EBUSY due to backlog correctly
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Petr Mladek authored
This reverts commit cf39bf58. The commit regression to users that define both console=ttyS1 and console=ttyS0 on the command line, see https://lkml.kernel.org/r/20170509082915.GA13236@bistromath.localdomain The kernel log messages always appeared only on one serial port. It is even documented in Documentation/admin-guide/serial-console.rst: "Note that you can only define one console per device type (serial, video)." The above mentioned commit changed the order in which the command line parameters are searched. As a result, the kernel log messages go to the last mentioned ttyS* instead of the first one. We long thought that using two console=ttyS* on the command line did not make sense. But then we realized that console= parameters were handled also by systemd, see http://0pointer.de/blog/projects/serial-console.html "By default systemd will instantiate one serial-getty@.service on the main kernel console, if it is not a virtual terminal." where "[4] If multiple kernel consoles are used simultaneously, the main console is the one listed first in /sys/class/tty/console/active, which is the last one listed on the kernel command line." This puts the original report into another light. The system is running in qemu. The first serial port is used to store the messages into a file. The second one is used to login to the system via a socket. It depends on systemd and the historic kernel behavior. By other words, systemd causes that it makes sense to define both console=ttyS1 console=ttyS0 on the command line. The kernel fix caused regression related to userspace (systemd) and need to be reverted. In addition, it went out that the fix helped only partially. The messages still were duplicated when the boot console was removed early by late_initcall(printk_late_init). Then the entire log was replayed when the same console was registered as a normal one. Link: 20170606160339.GC7604@pathway.suse.cz Cc: Aleksey Makarov <aleksey.makarov@linaro.org> Cc: Sabrina Dubroca <sd@queasysnail.net> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Robin Murphy <robin.murphy@arm.com>, Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Nair, Jayachandran" <Jayachandran.Nair@cavium.com> Cc: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reported-by:
Sabrina Dubroca <sd@queasysnail.net> Acked-by:
Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by:
Petr Mladek <pmladek@suse.com>
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Jessica Yu authored
I will be traveling in the upcoming months and it'll be much easier for me to access my kernel.org email rather than my work one. Change my email address in the MAINTAINERS file from jeyu@redhat.com to jeyu@kernel.org. Signed-off-by:Jessica Yu <jeyu@redhat.com>
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- 06 Jun, 2017 12 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) Made TCP congestion control documentation match current reality, from Anmol Sarma. 2) Various build warning and failure fixes from Arnd Bergmann. 3) Fix SKB list leak in ipv6_gso_segment(). 4) Use after free in ravb driver, from Eugeniu Rosca. 5) Don't use udp_poll() in ping protocol driver, from Eric Dumazet. 6) Don't crash in PCI error recovery of cxgb4 driver, from Guilherme Piccoli. 7) _SRC_NAT_DONE_BIT needs to be cleared using atomics, from Liping Zhang. 8) Use after free in vxlan deletion, from Mark Bloch. 9) Fix ordering of NAPI poll enabled in ethoc driver, from Max Filippov. 10) Fix stmmac hangs with TSO, from Niklas Cassel. 11) Fix crash in CALIPSO ipv6, from Richard Haines. 12) Clear nh_flags properly on mpls link up. From Roopa Prabhu. 13) Fix regression in sk_err socket error queue handling, noticed by ping applications. From Soheil Hassas Yeganeh. 14) Update mlx4/mlx5 MAINTAINERS information. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (78 commits) net: stmmac: fix a broken u32 less than zero check net: stmmac: fix completely hung TX when using TSO net: ethoc: enable NAPI before poll may be scheduled net: bridge: fix a null pointer dereference in br_afspec ravb: Fix use-after-free on `ifconfig eth0 down` net/ipv6: Fix CALIPSO causing GPF with datagram support net: stmmac: ensure jumbo_frm error return is correctly checked for -ve value Revert "sit: reload iphdr in ipip6_rcv" i40e/i40evf: proper update of the page_offset field i40e: Fix state flags for bit set and clean operations of PF iwlwifi: fix host command memory leaks iwlwifi: fix min API version for 7265D, 3168, 8000 and 8265 iwlwifi: mvm: clear new beacon command template struct iwlwifi: mvm: don't fail when removing a key from an inexisting sta iwlwifi: pcie: only use d0i3 in suspend/resume if system_pm is set to d0i3 iwlwifi: mvm: fix firmware debug restart recording iwlwifi: tt: move ucode_loaded check under mutex iwlwifi: mvm: support ibss in dqa mode iwlwifi: mvm: Fix command queue number on d0i3 flow iwlwifi: mvm: rs: start using LQ command color ... -
git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparcLinus Torvalds authored
Pull sparc fixes from David Miller: 1) Fix TLB context wrap races, from Pavel Tatashin. 2) Cure some gcc-7 build issues. 3) Handle invalid setup_hugepagesz command line values properly, from Liam R Howlett. 4) Copy TSB using the correct address shift for the huge TSB, from Mike Kravetz. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: sparc64: delete old wrap code sparc64: new context wrap sparc64: add per-cpu mm of secondary contexts sparc64: redefine first version sparc64: combine activate_mm and switch_mm sparc64: reset mm cpumask after wrap sparc/mm/hugepages: Fix setup_hugepagesz for invalid values. sparc: Machine description indices can vary sparc64: mm: fix copy_tsb to correctly copy huge page TSBs arch/sparc: support NR_CPUS = 4096 sparc64: Add __multi3 for gcc 7.x and later. sparc64: Fix build warnings with gcc 7. arch/sparc: increase CONFIG_NODES_SHIFT on SPARC64 to 5 -
David Rientjes authored
GCC explicitly does not warn for unused static inline functions for -Wunused-function. The manual states: Warn whenever a static function is declared but not defined or a non-inline static function is unused. Clang does warn for static inline functions that are unused. It turns out that suppressing the warnings avoids potentially complex #ifdef directives, which also reduces LOC. Suppress the warning for clang. Signed-off-by:
David Rientjes <rientjes@google.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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David S. Miller authored
Pavel Tatashin says: ==================== sparc64: context wrap fixes This patch series contains fixes for context wrap: when we are out of context ids, and need to get a new version. It fixes memory corruption issues which happen when more than number of context ids (currently set to 8K) number of processes are started simultaneously, and processes can get a wrong context. sparc64: new context wrap: - contains explanation of new wrap method, and also explanation of races that it solves sparc64: reset mm cpumask after wrap - explains issue of not reseting cpu mask on a wrap ==================== Signed-off-by:David S. Miller <davem@davemloft.net>
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Pavel Tatashin authored
The old method that is using xcall and softint to get new context id is deleted, as it is replaced by a method of using per_cpu_secondary_mm without xcall to perform the context wrap. Signed-off-by:
Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by:
Bob Picco <bob.picco@oracle.com> Reviewed-by:
Steven Sistare <steven.sistare@oracle.com> Signed-off-by:
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Pavel Tatashin authored
The current wrap implementation has a race issue: it is called outside of the ctx_alloc_lock, and also does not wait for all CPUs to complete the wrap. This means that a thread can get a new context with a new version and another thread might still be running with the same context. The problem is especially severe on CPUs with shared TLBs, like sun4v. I used the following test to very quickly reproduce the problem: - start over 8K processes (must be more than context IDs) - write and read values at a memory location in every process. Very quickly memory corruptions start happening, and what we read back does not equal what we wrote. Several approaches were explored before settling on this one: Approach 1: Move smp_new_mmu_context_version() inside ctx_alloc_lock, and wait for every process to complete the wrap. (Note: every CPU must WAIT before leaving smp_new_mmu_context_version_client() until every one arrives). This approach ends up with deadlocks, as some threads own locks which other threads are waiting for, and they never receive softint until these threads exit smp_new_mmu_context_version_client(). Since we do not allow the exit, deadlock happens. Approach 2: Handle wrap right during mondo interrupt. Use etrap/rtrap to enter into into C code, and issue new versions to every CPU. This approach adds some overhead to runtime: in switch_mm() we must add some checks to make sure that versions have not changed due to wrap while we were loading the new secondary context. (could be protected by PSTATE_IE but that degrades performance as on M7 and older CPUs as it takes 50 cycles for each access). Also, we still need a global per-cpu array of MMs to know where we need to load new contexts, otherwise we can change context to a thread that is going way (if we received mondo between switch_mm() and switch_to() time). Finally, there are some issues with window registers in rtrap() when context IDs are changed during CPU mondo time. The approach in this patch is the simplest and has almost no impact on runtime. We use the array with mm's where last secondary contexts were loaded onto CPUs and bump their versions to the new generation without changing context IDs. If a new process comes in to get a context ID, it will go through get_new_mmu_context() because of version mismatch. But the running processes do not need to be interrupted. And wrap is quicker as we do not need to xcall and wait for everyone to receive and complete wrap. Signed-off-by:
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Pavel Tatashin authored
The new wrap is going to use information from this array to figure out mm's that currently have valid secondary contexts setup. Signed-off-by:
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Pavel Tatashin authored
CTX_FIRST_VERSION defines the first context version, but also it defines first context. This patch redefines it to only include the first context version. Signed-off-by:
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Pavel Tatashin authored
The only difference between these two functions is that in activate_mm we unconditionally flush context. However, there is no need to keep this difference after fixing a bug where cpumask was not reset on a wrap. So, in this patch we combine these. Signed-off-by:
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Pavel Tatashin authored
After a wrap (getting a new context version) a process must get a new context id, which means that we would need to flush the context id from the TLB before running for the first time with this ID on every CPU. But, we use mm_cpumask to determine if this process has been running on this CPU before, and this mask is not reset after a wrap. So, there are two possible fixes for this issue: 1. Clear mm cpumask whenever mm gets a new context id 2. Unconditionally flush context every time process is running on a CPU This patch implements the first solution Signed-off-by:
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Liam R. Howlett authored
hugetlb_bad_size needs to be called on invalid values. Also change the pr_warn to a pr_err to better align with other platforms. Signed-off-by:
Liam R. Howlett <Liam.Howlett@Oracle.com> Signed-off-by:
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James Clarke authored
VIO devices were being looked up by their index in the machine description node block, but this often varies over time as devices are added and removed. Instead, store the ID and look up using the type, config handle and ID. Signed-off-by:
James Clarke <jrtc27@jrtc27.com> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112541Signed-off-by:
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