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2016-05-17Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto update from Herbert Xu: "API: - Crypto self tests can now be disabled at boot/run time. - Add async support to algif_aead. Algorithms: - A large number of fixes to MPI from Nicolai Stange. - Performance improvement for HMAC DRBG. Drivers: - Use generic crypto engine in omap-des. - Merge ppc4xx-rng and crypto4xx drivers. - Fix lockups in sun4i-ss driver by disabling IRQs. - Add DMA engine support to ccp. - Reenable talitos hash algorithms. - Add support for Hisilicon SoC RNG. - Add basic crypto driver for the MXC SCC. Others: - Do not allocate crypto hash tfm in NORECLAIM context in ecryptfs" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (77 commits) crypto: qat - change the adf_ctl_stop_devices to void crypto: caam - fix caam_jr_alloc() ret code crypto: vmx - comply with ABIs that specify vrsave as reserved. crypto: testmgr - Add a flag allowing the self-tests to be disabled at runtime. crypto: ccp - constify ccp_actions structure crypto: marvell/cesa - Use dma_pool_zalloc crypto: qat - make adf_vf_isr.c dependant on IOV config crypto: qat - Fix typo in comments lib: asn1_decoder - add MODULE_LICENSE("GPL") crypto: omap-sham - Use dma_request_chan() for requesting DMA channel crypto: omap-des - Use dma_request_chan() for requesting DMA channel crypto: omap-aes - Use dma_request_chan() for requesting DMA channel crypto: omap-des - Integrate with the crypto engine framework crypto: s5p-sss - fix incorrect usage of scatterlists api crypto: s5p-sss - Fix missed interrupts when working with 8 kB blocks crypto: s5p-sss - Use common BIT macro crypto: mxc-scc - fix unwinding in mxc_scc_crypto_register() crypto: mxc-scc - signedness bugs in mxc_scc_ablkcipher_req_init() crypto: talitos - fix ahash algorithms registration crypto: ccp - Ensure all dependencies are specified ...
2016-05-16Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main changes are: - Documentation updates, including fixes to the design-level requirements documentation and a fixed version of the design-level data-structure documentation. These fixes include removing cartoons and getting rid of the html/htmlx duplication. - Further improvements to the new-age expedited grace periods. - Miscellaneous fixes. - Torture-test changes, including a new rcuperf module for measuring RCU grace-period performance and scalability, which is useful for the expedited-grace-period changes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits) rcutorture: Add boot-time adjustment of leaf fanout rcutorture: Add irqs-disabled test for call_rcu() rcutorture: Dump trace buffer upon shutdown rcutorture: Don't rebuild identical kernel rcutorture: Add OS-jitter capability documentation: Add documentation for RCU's major data structures rcutorture: Convert test duration to seconds early torture: Kill qemu, not parent process torture: Clarify refusal to run more than one torture test rcutorture: Consider FROZEN hotplug notifier transitions rcutorture: Remove redundant initialization to zero rcuperf: Do not wake up shutdown wait queue if "shutdown" is false. rcutorture: Add largish-system rcuperf scenario rcutorture: Avoid RCU CPU stall warning and RT throttling rcutorture: Add rcuperf holdoff boot parameter to reduce interference rcutorture: Make scripts analyze rcuperf trace data, if present rcutorture: Make rcuperf collect expedited event-trace data rcutorture: Print measure of batching efficiency rcutorture: Set rcuperf writer kthreads to real-time priority rcutorture: Bind rcuperf reader/writer kthreads to CPUs ...
2016-05-16Merge branch 'core-lib-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core/lib update from Ingo Molnar: "This contains a single commit that removes an unused facility that the scheduler used to make use of" * 'core-lib-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: lib/proportions: Remove unused code
2016-05-14Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs fixes from Al Viro: "Overlayfs fixes from Miklos, assorted fixes from me. Stable fodder of varying severity, all sat in -next for a while" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ovl: ignore permissions on underlying lookup vfs: add lookup_hash() helper vfs: rename: check backing inode being equal vfs: add vfs_select_inode() helper get_rock_ridge_filename(): handle malformed NM entries ecryptfs: fix handling of directory opening atomic_open(): fix the handling of create_error fix the copy vs. map logics in blk_rq_map_user_iov() do_splice_to(): cap the size before passing to ->splice_read()
2016-05-12KEYS: Fix ASN.1 indefinite length object parsingDavid Howells
This fixes CVE-2016-0758. In the ASN.1 decoder, when the length field of an ASN.1 value is extracted, it isn't validated against the remaining amount of data before being added to the cursor. With a sufficiently large size indicated, the check: datalen - dp < 2 may then fail due to integer overflow. Fix this by checking the length indicated against the amount of remaining data in both places a definite length is determined. Whilst we're at it, make the following changes: (1) Check the maximum size of extended length does not exceed the capacity of the variable it's being stored in (len) rather than the type that variable is assumed to be (size_t). (2) Compare the EOC tag to the symbolic constant ASN1_EOC rather than the integer 0. (3) To reduce confusion, move the initialisation of len outside of: for (len = 0; n > 0; n--) { since it doesn't have anything to do with the loop counter n. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Acked-by: Peter Jones <pjones@redhat.com>
2016-05-11Merge branch 'ovl-fixes' into for-linusAl Viro
2016-05-06lib/stackdepot: avoid to return 0 handleJoonsoo Kim
Recently, we allow to save the stacktrace whose hashed value is 0. It causes the problem that stackdepot could return 0 even if in success. User of stackdepot cannot distinguish whether it is success or not so we need to solve this problem. In this patch, 1 bit are added to handle and make valid handle none 0 by setting this bit. After that, valid handle will not be 0 and 0 handle will represent failure correctly. Fixes: 33334e25769c ("lib/stackdepot.c: allow the stack trace hash to be zero") Link: http://lkml.kernel.org/r/1462252403-1106-1-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-03lib: asn1_decoder - add MODULE_LICENSE("GPL")Tudor Ambarus
A kernel taint results when loading the rsa_generic module: root@(none):~# modprobe rsa_generic asn1_decoder: module license 'unspecified' taints kernel. Disabling lock debugging due to kernel taint "Tainting" of the kernel is (usually) a way of indicating that a proprietary module has been inserted, which is not the case here. Signed-off-by: Tudor Ambarus <tudor-dan.ambarus@nxp.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-29lib/stackdepot.c: allow the stack trace hash to be zeroAlexander Potapenko
Do not bail out from depot_save_stack() if the stack trace has zero hash. Initially depot_save_stack() silently dropped stack traces with zero hashes, however there's actually no point in reserving this zero value. Reported-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-27Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: * Documentation updates, including fixes to the design-level requirements documentation and a fixed version of the design-level data-structure documentation. These fixes include removing cartoons and getting rid of the html/htmlx duplication. * Further improvements to the new-age expedited grace periods. * Miscellaneous fixes. * Torture-test changes, including a new rcuperf module for measuring RCU grace-period performance and scalability, which is useful for the expedited-grace-period changes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-17Merge tag 'driver-core-4.6-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull misc fixes from Greg KH: "Here are three small fixes for 4.6-rc4. Two fix up some lz4 issues with big endian systems, and the remaining one resolves a minor debugfs issue that was reported. All have been in linux-next with no reported issues" * tag 'driver-core-4.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: lib: lz4: cleanup unaligned access efficiency detection lib: lz4: fixed zram with lz4 on big endian machines debugfs: Make automount point inodes permanently empty
2016-04-13lib: lz4: cleanup unaligned access efficiency detectionRui Salvaterra
These identifiers are bogus. The interested architectures should define HAVE_EFFICIENT_UNALIGNED_ACCESS whenever relevant to do so. If this isn't true for some arch, it should be fixed in the arch definition. Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-13lib: lz4: fixed zram with lz4 on big endian machinesRui Salvaterra
Based on Sergey's test patch [1], this fixes zram with lz4 compression on big endian cpus. Note that the 64-bit preprocessor test is not a cleanup, it's part of the fix, since those identifiers are bogus (for example, __ppc64__ isn't defined anywhere else in the kernel, which means we'd fall into the 32-bit definitions on ppc64). Tested on ppc64 with no regression on x86_64. [1] http://marc.info/?l=linux-kernel&m=145994470805853&w=4 Cc: stable@vger.kernel.org Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-13Merge tag 'keys-fixes-20160412' of ↵James Morris
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into for-linus
2016-04-08fix the copy vs. map logics in blk_rq_map_user_iov()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-06lib/test_bpf: Add additional BPF_ADD testsNaveen N. Rao
Some of these tests proved useful with the powerpc eBPF JIT port due to sign-extended 16-bit immediate loads. Though some of these aspects get covered in other tests, it is better to have explicit tests so as to quickly tag the precise problem. Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06lib/test_bpf: Add test to check for result of 32-bit add that overflowsNaveen N. Rao
BPF_ALU32 and BPF_ALU64 tests for adding two 32-bit values that results in 32-bit overflow. Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06lib/test_bpf: Add tests for unsigned BPF_JGTNaveen N. Rao
Unsigned Jump-if-Greater-Than. Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06lib/test_bpf: Fix JMP_JSET testsNaveen N. Rao
JMP_JSET tests incorrectly used BPF_JNE. Fix the same. Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06assoc_array: don't call compare_object() on a nodeJerome Marchand
Changes since V1: fixed the description and added KASan warning. In assoc_array_insert_into_terminal_node(), we call the compare_object() method on all non-empty slots, even when they're not leaves, passing a pointer to an unexpected structure to compare_object(). Currently it causes an out-of-bound read access in keyring_compare_object detected by KASan (see below). The issue is easily reproduced with keyutils testsuite. Only call compare_object() when the slot is a leave. KASan warning: ================================================================== BUG: KASAN: slab-out-of-bounds in keyring_compare_object+0x213/0x240 at addr ffff880060a6f838 Read of size 8 by task keyctl/1655 ============================================================================= BUG kmalloc-192 (Not tainted): kasan: bad access detected ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Allocated in assoc_array_insert+0xfd0/0x3a60 age=69 cpu=1 pid=1647 ___slab_alloc+0x563/0x5c0 __slab_alloc+0x51/0x90 kmem_cache_alloc_trace+0x263/0x300 assoc_array_insert+0xfd0/0x3a60 __key_link_begin+0xfc/0x270 key_create_or_update+0x459/0xaf0 SyS_add_key+0x1ba/0x350 entry_SYSCALL_64_fastpath+0x12/0x76 INFO: Slab 0xffffea0001829b80 objects=16 used=8 fp=0xffff880060a6f550 flags=0x3fff8000004080 INFO: Object 0xffff880060a6f740 @offset=5952 fp=0xffff880060a6e5d1 Bytes b4 ffff880060a6f730: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f740: d1 e5 a6 60 00 88 ff ff 0e 00 00 00 00 00 00 00 ...`............ Object ffff880060a6f750: 02 cf 8e 60 00 88 ff ff 02 c0 8e 60 00 88 ff ff ...`.......`.... Object ffff880060a6f760: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f770: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f790: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f7a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f7b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f7c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f7d0: 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f7e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object ffff880060a6f7f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ CPU: 0 PID: 1655 Comm: keyctl Tainted: G B 4.5.0-rc4-kasan+ #291 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 0000000000000000 000000001b2800b4 ffff880060a179e0 ffffffff81b60491 ffff88006c802900 ffff880060a6f740 ffff880060a17a10 ffffffff815e2969 ffff88006c802900 ffffea0001829b80 ffff880060a6f740 ffff880060a6e650 Call Trace: [<ffffffff81b60491>] dump_stack+0x85/0xc4 [<ffffffff815e2969>] print_trailer+0xf9/0x150 [<ffffffff815e9454>] object_err+0x34/0x40 [<ffffffff815ebe50>] kasan_report_error+0x230/0x550 [<ffffffff819949be>] ? keyring_get_key_chunk+0x13e/0x210 [<ffffffff815ec62d>] __asan_report_load_n_noabort+0x5d/0x70 [<ffffffff81994cc3>] ? keyring_compare_object+0x213/0x240 [<ffffffff81994cc3>] keyring_compare_object+0x213/0x240 [<ffffffff81bc238c>] assoc_array_insert+0x86c/0x3a60 [<ffffffff81bc1b20>] ? assoc_array_cancel_edit+0x70/0x70 [<ffffffff8199797d>] ? __key_link_begin+0x20d/0x270 [<ffffffff8199786c>] __key_link_begin+0xfc/0x270 [<ffffffff81993389>] key_create_or_update+0x459/0xaf0 [<ffffffff8128ce0d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff81992f30>] ? key_type_lookup+0xc0/0xc0 [<ffffffff8199e19d>] ? lookup_user_key+0x13d/0xcd0 [<ffffffff81534763>] ? memdup_user+0x53/0x80 [<ffffffff819983ea>] SyS_add_key+0x1ba/0x350 [<ffffffff81998230>] ? key_get_type_from_user.constprop.6+0xa0/0xa0 [<ffffffff828bcf4e>] ? retint_user+0x18/0x23 [<ffffffff8128cc7e>] ? trace_hardirqs_on_caller+0x3fe/0x580 [<ffffffff81004017>] ? trace_hardirqs_on_thunk+0x17/0x19 [<ffffffff828bc432>] entry_SYSCALL_64_fastpath+0x12/0x76 Memory state around the buggy address: ffff880060a6f700: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff880060a6f780: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc >ffff880060a6f800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff880060a6f880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff880060a6f900: fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00 ================================================================== Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: stable@vger.kernel.org
2016-04-05lib/mpi: mpi_read_raw_from_sgl(): fix out-of-bounds buffer accessNicolai Stange
Within the copying loop in mpi_read_raw_from_sgl(), the last input SGE's byte count gets artificially extended as follows: if (sg_is_last(sg) && (len % BYTES_PER_MPI_LIMB)) len += BYTES_PER_MPI_LIMB - (len % BYTES_PER_MPI_LIMB); Within the following byte copying loop, this causes reads beyond that SGE's allocated buffer: BUG: KASAN: slab-out-of-bounds in mpi_read_raw_from_sgl+0x331/0x650 at addr ffff8801e168d4d8 Read of size 1 by task systemd-udevd/721 [...] Call Trace: [<ffffffff818c4d35>] dump_stack+0xbc/0x117 [<ffffffff818c4c79>] ? _atomic_dec_and_lock+0x169/0x169 [<ffffffff814af5d1>] ? print_section+0x61/0xb0 [<ffffffff814b1109>] print_trailer+0x179/0x2c0 [<ffffffff814bc524>] object_err+0x34/0x40 [<ffffffff814bfdc7>] kasan_report_error+0x307/0x8c0 [<ffffffff814bf315>] ? kasan_unpoison_shadow+0x35/0x50 [<ffffffff814bf38e>] ? kasan_kmalloc+0x5e/0x70 [<ffffffff814c0ad1>] kasan_report+0x71/0xa0 [<ffffffff81938171>] ? mpi_read_raw_from_sgl+0x331/0x650 [<ffffffff814bf1a6>] __asan_load1+0x46/0x50 [<ffffffff81938171>] mpi_read_raw_from_sgl+0x331/0x650 [<ffffffff817f41b6>] rsa_verify+0x106/0x260 [<ffffffff817f40b0>] ? rsa_set_pub_key+0xf0/0xf0 [<ffffffff818edc79>] ? sg_init_table+0x29/0x50 [<ffffffff817f4d22>] ? pkcs1pad_sg_set_buf+0xb2/0x2e0 [<ffffffff817f5b74>] pkcs1pad_verify+0x1f4/0x2b0 [<ffffffff81831057>] public_key_verify_signature+0x3a7/0x5e0 [<ffffffff81830cb0>] ? public_key_describe+0x80/0x80 [<ffffffff817830f0>] ? keyring_search_aux+0x150/0x150 [<ffffffff818334a4>] ? x509_request_asymmetric_key+0x114/0x370 [<ffffffff814b83f0>] ? kfree+0x220/0x370 [<ffffffff818312c2>] public_key_verify_signature_2+0x32/0x50 [<ffffffff81830b5c>] verify_signature+0x7c/0xb0 [<ffffffff81835d0c>] pkcs7_validate_trust+0x42c/0x5f0 [<ffffffff813c391a>] system_verify_data+0xca/0x170 [<ffffffff813c3850>] ? top_trace_array+0x9b/0x9b [<ffffffff81510b29>] ? __vfs_read+0x279/0x3d0 [<ffffffff8129372f>] mod_verify_sig+0x1ff/0x290 [...] The exact purpose of the len extension isn't clear to me, but due to its form, I suspect that it's a leftover somehow accounting for leading zero bytes within the most significant output limb. Note however that without that len adjustement, the total number of bytes ever processed by the inner loop equals nbytes and thus, the last output limb gets written at this point. Thus the net effect of the len adjustement cited above is just to keep the inner loop running for some more iterations, namely < BYTES_PER_MPI_LIMB ones, reading some extra bytes from beyond the last SGE's buffer and discarding them afterwards. Fix this issue by purging the extension of len beyond the last input SGE's buffer length. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_raw_from_sgl(): sanitize meaning of indicesNicolai Stange
Within the byte reading loop in mpi_read_raw_sgl(), there are two housekeeping indices used, z and x. At all times, the index z represents the number of output bytes covered by the input SGEs for which processing has completed so far. This includes any leading zero bytes within the most significant limb. The index x changes its meaning after the first outer loop's iteration though: while processing the first input SGE, it represents "number of leading zero bytes in most significant output limb" + "current position within current SGE" For the remaining SGEs OTOH, x corresponds just to "current position within current SGE" After all, it is only the sum of z and x that has any meaning for the output buffer and thus, the "number of leading zero bytes in most significant output limb" part can be moved away from x into z from the beginning, opening up the opportunity for cleaner code. Before the outer loop iterating over the SGEs, don't initialize z with zero, but with the number of leading zero bytes in the most significant output limb. For the inner loop iterating over a single SGE's bytes, get rid of the buf_shift offset to x' bounds and let x run from zero to sg->length - 1. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_raw_from_sgl(): fix nbits calculationNicolai Stange
The number of bits, nbits, is calculated in mpi_read_raw_from_sgl() as follows: nbits = nbytes * 8; Afterwards, the number of leading zero bits of the first byte get subtracted: nbits -= count_leading_zeros(*(u8 *)(sg_virt(sgl) + lzeros)); However, count_leading_zeros() takes an unsigned long and thus, the u8 gets promoted to an unsigned long. Thus, the above doesn't subtract the number of leading zeros in the most significant nonzero input byte from nbits, but the number of leading zeros of the most significant nonzero input byte promoted to unsigned long, i.e. BITS_PER_LONG - 8 too many. Fix this by subtracting count_leading_zeros(...) - (BITS_PER_LONG - 8) from nbits only. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_raw_from_sgl(): purge redundant clearing of nbitsNicolai Stange
In mpi_read_raw_from_sgl(), unsigned nbits is calculated as follows: nbits = nbytes * 8; and redundantly cleared later on if nbytes == 0: if (nbytes > 0) ... else nbits = 0; Purge this redundant clearing for the sake of clarity. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_raw_from_sgl(): don't include leading zero SGEs in nbytesNicolai Stange
At the very beginning of mpi_read_raw_from_sgl(), the leading zeros of the input scatterlist are counted: lzeros = 0; for_each_sg(sgl, sg, ents, i) { ... if (/* sg contains nonzero bytes */) break; /* sg contains nothing but zeros here */ ents--; lzeros = 0; } Later on, the total number of trailing nonzero bytes is calculated by subtracting the number of leading zero bytes from the total number of input bytes: nbytes -= lzeros; However, since lzeros gets reset to zero for each completely zero leading sg in the loop above, it doesn't include those. Besides wasting resources by allocating a too large output buffer, this mistake propagates into the calculation of x, the number of leading zeros within the most significant output limb: x = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB; What's more, the low order bytes of the output, equal in number to the extra bytes in nbytes, are left uninitialized. Fix this by adjusting nbytes for each completely zero leading scatterlist entry. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_raw_from_sgl(): replace len argument by nbytesNicolai Stange
Currently, the nbytes local variable is calculated from the len argument as follows: ... mpi_read_raw_from_sgl(..., unsigned int len) { unsigned nbytes; ... if (!ents) nbytes = 0; else nbytes = len - lzeros; ... } Given that nbytes is derived from len in a trivial way and that the len argument is shadowed by a local len variable in several loops, this is just confusing. Rename the len argument to nbytes and get rid of the nbytes local variable. Do the nbytes calculation in place. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_buffer(): fix buffer overflowNicolai Stange
Currently, mpi_read_buffer() writes full limbs to the output buffer and moves memory around to purge leading zero limbs afterwards. However, with commit 9cbe21d8f89d ("lib/mpi: only require buffers as big as needed for the integer") the caller is only required to provide a buffer large enough to hold the result without the leading zeros. This might result in a buffer overflow for small MP numbers with leading zeros. Fix this by coping the result to its final destination within the output buffer and not copying the leading zeros at all. Fixes: 9cbe21d8f89d ("lib/mpi: only require buffers as big as needed for the integer") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_buffer(): replace open coded endian conversionNicolai Stange
Currently, the endian conversion from CPU order to BE is open coded in mpi_read_buffer(). Replace this by the centrally provided cpu_to_be*() macros. Copy from the temporary storage on stack to the destination buffer by means of memcpy(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_read_buffer(): optimize skipping of leading zero limbsNicolai Stange
Currently, if the number of leading zeros is greater than fits into a complete limb, mpi_read_buffer() skips them by iterating over them limb-wise. Instead of skipping the high order zero limbs within the loop as shown above, adjust the copying loop's bounds. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_write_sgl(): replace open coded endian conversionNicolai Stange
Currently, the endian conversion from CPU order to BE is open coded in mpi_write_sgl(). Replace this by the centrally provided cpu_to_be*() macros. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_write_sgl(): fix out-of-bounds stack accessNicolai Stange
Within the copying loop in mpi_write_sgl(), we have if (lzeros) { mpi_limb_t *limb1 = (void *)p - sizeof(alimb); mpi_limb_t *limb2 = (void *)p - sizeof(alimb) + lzeros; *limb1 = *limb2; ... } where p points past the end of alimb2 which lives on the stack and contains the current limb in BE order. The purpose of the above is to shift the non-zero bytes of alimb2 to its beginning in memory, i.e. to skip its leading zero bytes. However, limb2 points somewhere into the middle of alimb2 and thus, reading *limb2 pulls in lzero bytes from somewhere. Indeed, KASAN splats: BUG: KASAN: stack-out-of-bounds in mpi_write_to_sgl+0x4e3/0x6f0 at addr ffff8800cb04f601 Read of size 8 by task systemd-udevd/391 page:ffffea00032c13c0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x3fff8000000000() page dumped because: kasan: bad access detected CPU: 3 PID: 391 Comm: systemd-udevd Tainted: G B L 4.5.0-next-20160316+ #12 [...] Call Trace: [<ffffffff8194889e>] dump_stack+0xdc/0x15e [<ffffffff819487c2>] ? _atomic_dec_and_lock+0xa2/0xa2 [<ffffffff814892b5>] ? __dump_page+0x185/0x330 [<ffffffff8150ffd6>] kasan_report_error+0x5e6/0x8b0 [<ffffffff814724cd>] ? kzfree+0x2d/0x40 [<ffffffff819c5bce>] ? mpi_free_limb_space+0xe/0x20 [<ffffffff819c469e>] ? mpi_powm+0x37e/0x16f0 [<ffffffff815109f1>] kasan_report+0x71/0xa0 [<ffffffff819c0353>] ? mpi_write_to_sgl+0x4e3/0x6f0 [<ffffffff8150ed34>] __asan_load8+0x64/0x70 [<ffffffff819c0353>] mpi_write_to_sgl+0x4e3/0x6f0 [<ffffffff819bfe70>] ? mpi_set_buffer+0x620/0x620 [<ffffffff819c0e6f>] ? mpi_cmp+0xbf/0x180 [<ffffffff8186e282>] rsa_verify+0x202/0x260 What's more, since lzeros can be anything from 1 to sizeof(mpi_limb_t)-1, the above will cause unaligned accesses which is bad on non-x86 archs. Fix the issue, by preparing the starting point p for the upcoming copy operation instead of shifting the source memory, i.e. alimb2. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_write_sgl(): purge redundant pointer arithmeticNicolai Stange
Within the copying loop in mpi_write_sgl(), we have if (lzeros) { ... p -= lzeros; y = lzeros; } p = p - (sizeof(alimb) - y); If lzeros == 0, then y == 0, too. Thus, lzeros gets subtracted and added back again to p. Purge this redundancy. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_write_sgl(): fix style issue with lzero decrementNicolai Stange
Within the copying loop in mpi_write_sgl(), we have if (lzeros > 0) { ... lzeros -= sizeof(alimb); } However, at this point, lzeros < sizeof(alimb) holds. Make this fact explicit by rewriting the above to if (lzeros) { ... lzeros = 0; } Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05lib/mpi: mpi_write_sgl(): fix skipping of leading zero limbsNicolai Stange
Currently, if the number of leading zeros is greater than fits into a complete limb, mpi_write_sgl() skips them by iterating over them limb-wise. However, it fails to adjust its internal leading zeros tracking variable, lzeros, accordingly: it does a p -= sizeof(alimb); continue; which should really have been a lzeros -= sizeof(alimb); continue; Since lzeros never decreases if its initial value >= sizeof(alimb), nothing gets copied by mpi_write_sgl() in that case. Instead of skipping the high order zero limbs within the loop as shown above, fix the issue by adjusting the copying loop's bounds. Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-01lib/proportions: Remove unused codeRichard Cochran
By accident I stumbled across code that is no longer used. According to git grep, the global functions in lib/proportions.c are not used anywhere. This patch removes the old, unused code. Peter Zijlstra further commented: "Ah indeed, that got replaced with the flex proportion code a while back." Signed-off-by: Richard Cochran <rcochran@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/4265b49bed713fbe3faaf8c05da0e1792f09c0b3.1459432020.git.rcochran@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31rcutorture: Add RCU grace-period performance testsPaul E. McKenney
This commit adds a new rcuperf module that carries out simple performance tests of RCU grace periods. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-03-25kasan: test fix: warn if the UAF could not be detected in kmalloc_uaf2Alexander Potapenko
Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25mm, kasan: stackdepot implementation. Enable stackdepot for SLABAlexander Potapenko
Implement the stack depot and provide CONFIG_STACKDEPOT. Stack depot will allow KASAN store allocation/deallocation stack traces for memory chunks. The stack traces are stored in a hash table and referenced by handles which reside in the kasan_alloc_meta and kasan_free_meta structures in the allocated memory chunks. IRQ stack traces are cut below the IRQ entry point to avoid unnecessary duplication. Right now stackdepot support is only enabled in SLAB allocator. Once KASAN features in SLAB are on par with those in SLUB we can switch SLUB to stackdepot as well, thus removing the dependency on SLUB stack bookkeeping, which wastes a lot of memory. This patch is based on the "mm: kasan: stack depots" patch originally prepared by Dmitry Chernenkov. Joonsoo has said that he plans to reuse the stackdepot code for the mm/page_owner.c debugging facility. [akpm@linux-foundation.org: s/depot_stack_handle/depot_stack_handle_t] [aryabinin@virtuozzo.com: comment style fixes] Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25mm, kasan: SLAB supportAlexander Potapenko
Add KASAN hooks to SLAB allocator. This patch is based on the "mm: kasan: unified support for SLUB and SLAB allocators" patch originally prepared by Dmitry Chernenkov. Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25kasan: modify kmalloc_large_oob_right(), add kmalloc_pagealloc_oob_right()Alexander Potapenko
This patchset implements SLAB support for KASAN Unlike SLUB, SLAB doesn't store allocation/deallocation stacks for heap objects, therefore we reimplement this feature in mm/kasan/stackdepot.c. The intention is to ultimately switch SLUB to use this implementation as well, which will save a lot of memory (right now SLUB bloats each object by 256 bytes to store the allocation/deallocation stacks). Also neither SLUB nor SLAB delay the reuse of freed memory chunks, which is necessary for better detection of use-after-free errors. We introduce memory quarantine (mm/kasan/quarantine.c), which allows delayed reuse of deallocated memory. This patch (of 7): Rename kmalloc_large_oob_right() to kmalloc_pagealloc_oob_right(), as the test only checks the page allocator functionality. Also reimplement kmalloc_large_oob_right() so that the test allocates a large enough chunk of memory that still does not trigger the page allocator fallback. Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-23parisc,metag: Implement CONFIG_DEBUG_STACK_USAGE optionHelge Deller
On parisc and metag the stack grows upwards, so for those we need to scan the stack downwards in order to calculate how much stack a process has used. Tested on a 64bit parisc kernel. Signed-off-by: Helge Deller <deller@gmx.de>
2016-03-22ubsan: fix tree-wide -Wmaybe-uninitialized false positivesAndrey Ryabinin
-fsanitize=* options makes GCC less smart than usual and increase number of 'maybe-uninitialized' false-positives. So this patch does two things: * Add -Wno-maybe-uninitialized to CFLAGS_UBSAN which will disable all such warnings for instrumented files. * Remove CONFIG_UBSAN_SANITIZE_ALL from all[yes|mod]config builds. So the all[yes|mod]config build goes without -fsanitize=* and still with -Wmaybe-uninitialized. Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22kernel: add kcov code coverageDmitry Vyukov
kcov provides code coverage collection for coverage-guided fuzzing (randomized testing). Coverage-guided fuzzing is a testing technique that uses coverage feedback to determine new interesting inputs to a system. A notable user-space example is AFL (http://lcamtuf.coredump.cx/afl/). However, this technique is not widely used for kernel testing due to missing compiler and kernel support. kcov does not aim to collect as much coverage as possible. It aims to collect more or less stable coverage that is function of syscall inputs. To achieve this goal it does not collect coverage in soft/hard interrupts and instrumentation of some inherently non-deterministic or non-interesting parts of kernel is disbled (e.g. scheduler, locking). Currently there is a single coverage collection mode (tracing), but the API anticipates additional collection modes. Initially I also implemented a second mode which exposes coverage in a fixed-size hash table of counters (what Quentin used in his original patch). I've dropped the second mode for simplicity. This patch adds the necessary support on kernel side. The complimentary compiler support was added in gcc revision 231296. We've used this support to build syzkaller system call fuzzer, which has found 90 kernel bugs in just 2 months: https://github.com/google/syzkaller/wiki/Found-Bugs We've also found 30+ bugs in our internal systems with syzkaller. Another (yet unexplored) direction where kcov coverage would greatly help is more traditional "blob mutation". For example, mounting a random blob as a filesystem, or receiving a random blob over wire. Why not gcov. Typical fuzzing loop looks as follows: (1) reset coverage, (2) execute a bit of code, (3) collect coverage, repeat. A typical coverage can be just a dozen of basic blocks (e.g. an invalid input). In such context gcov becomes prohibitively expensive as reset/collect coverage steps depend on total number of basic blocks/edges in program (in case of kernel it is about 2M). Cost of kcov depends only on number of executed basic blocks/edges. On top of that, kernel requires per-thread coverage because there are always background threads and unrelated processes that also produce coverage. With inlined gcov instrumentation per-thread coverage is not possible. kcov exposes kernel PCs and control flow to user-space which is insecure. But debugfs should not be mapped as user accessible. Based on a patch by Quentin Casasnovas. [akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode'] [akpm@linux-foundation.org: unbreak allmodconfig] [akpm@linux-foundation.org: follow x86 Makefile layout standards] Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: syzkaller <syzkaller@googlegroups.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Tavis Ormandy <taviso@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Kees Cook <keescook@google.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: David Drysdale <drysdale@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-21Merge branch 'core-objtool-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull 'objtool' stack frame validation from Ingo Molnar: "This tree adds a new kernel build-time object file validation feature (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation. It was written by and is maintained by Josh Poimboeuf. The motivation: there's a category of hard to find kernel bugs, most of them in assembly code (but also occasionally in C code), that degrades the quality of kernel stack dumps/backtraces. These bugs are hard to detect at the source code level. Such bugs result in incorrect/incomplete backtraces most of time - but can also in some rare cases result in crashes or other undefined behavior. The build time correctness checking is done via the new 'objtool' user-space utility that was written for this purpose and which is hosted in the kernel repository in tools/objtool/. The tool's (very simple) UI and source code design is shaped after Git and perf and shares quite a bit of infrastructure with tools/perf (which tooling infrastructure sharing effort got merged via perf and is already upstream). Objtool follows the well-known kernel coding style. Objtool does not try to check .c or .S files, it instead analyzes the resulting .o generated machine code from first principles: it decodes the instruction stream and interprets it. (Right now objtool supports the x86-64 architecture.) From tools/objtool/Documentation/stack-validation.txt: "The kernel CONFIG_STACK_VALIDATION option enables a host tool named objtool which runs at compile time. It has a "check" subcommand which analyzes every .o file and ensures the validity of its stack metadata. It enforces a set of rules on asm code and C inline assembly code so that stack traces can be reliable. Currently it only checks frame pointer usage, but there are plans to add CFI validation for C files and CFI generation for asm files. For each function, it recursively follows all possible code paths and validates the correct frame pointer state at each instruction. It also follows code paths involving special sections, like .altinstructions, __jump_table, and __ex_table, which can add alternative execution paths to a given instruction (or set of instructions). Similarly, it knows how to follow switch statements, for which gcc sometimes uses jump tables." When this new kernel option is enabled (it's disabled by default), the tool, if it finds any suspicious assembly code pattern, outputs warnings in compiler warning format: warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup warning: objtool:__schedule()+0x3c0: duplicate frame pointer save warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer ... so that scripts that pick up compiler warnings will notice them. All known warnings triggered by the tool are fixed by the tree, most of the commits in fact prepare the kernel to be warning-free. Most of them are bugfixes or cleanups that stand on their own, but there are also some annotations of 'special' stack frames for justified cases such entries to JIT-ed code (BPF) or really special boot time code. There are two other long-term motivations behind this tool as well: - To improve the quality and reliability of kernel stack frames, so that they can be used for optimized live patching. - To create independent infrastructure to check the correctness of CFI stack frames at build time. CFI debuginfo is notoriously unreliable and we cannot use it in the kernel as-is without extra checking done both on the kernel side and on the build side. The quality of kernel stack frames matters to debuggability as well, so IMO we can merge this without having to consider the live patching or CFI debuginfo angle" * 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) objtool: Only print one warning per function objtool: Add several performance improvements tools: Copy hashtable.h into tools directory objtool: Fix false positive warnings for functions with multiple switch statements objtool: Rename some variables and functions objtool: Remove superflous INIT_LIST_HEAD objtool: Add helper macros for traversing instructions objtool: Fix false positive warnings related to sibling calls objtool: Compile with debugging symbols objtool: Detect infinite recursion objtool: Prevent infinite recursion in noreturn detection objtool: Detect and warn if libelf is missing and don't break the build tools: Support relative directory path for 'O=' objtool: Support CROSS_COMPILE x86/asm/decoder: Use explicitly signed chars objtool: Enable stack metadata validation on 64-bit x86 objtool: Add CONFIG_STACK_VALIDATION option objtool: Add tool to perform compile-time stack metadata validation x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard sched: Always inline context_switch() ...
2016-03-20Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio/vhost updates from Michael Tsirkin: "New features, performance improvements, cleanups: - basic polling support for vhost - rework virtio to optionally use DMA API, fixing it on Xen - balloon stats gained a new entry - using the new napi_alloc_skb speeds up virtio net - virtio blk stats can now be read while another VCPU is busy inflating or deflating the balloon plus misc cleanups in various places" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio_net: replace netdev_alloc_skb_ip_align() with napi_alloc_skb() vhost_net: basic polling support vhost: introduce vhost_vq_avail_empty() vhost: introduce vhost_has_work() virtio_balloon: Allow to resize and update the balloon stats in parallel virtio_balloon: Use a workqueue instead of "vballoon" kthread virtio/s390: size of SET_IND payload virtio/s390: use dev_to_virtio vhost: rename vhost_init_used() vhost: rename cross-endian helpers virtio_blk: VIRTIO_BLK_F_WCE->VIRTIO_BLK_F_FLUSH vring: Use the DMA API on Xen virtio_pci: Use the DMA API if enabled virtio_mmio: Use the DMA API if enabled virtio: Add improved queue allocation API virtio_ring: Support DMA APIs vring: Introduce vring_use_dma_api() s390/dma: Allow per device dma ops alpha/dma: use common noop dma ops dma: Provide simple noop dma ops
2016-03-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: "Highlights: 1) Support more Realtek wireless chips, from Jes Sorenson. 2) New BPF types for per-cpu hash and arrap maps, from Alexei Starovoitov. 3) Make several TCP sysctls per-namespace, from Nikolay Borisov. 4) Allow the use of SO_REUSEPORT in order to do per-thread processing of incoming TCP/UDP connections. The muxing can be done using a BPF program which hashes the incoming packet. From Craig Gallek. 5) Add a multiplexer for TCP streams, to provide a messaged based interface. BPF programs can be used to determine the message boundaries. From Tom Herbert. 6) Add 802.1AE MACSEC support, from Sabrina Dubroca. 7) Avoid factorial complexity when taking down an inetdev interface with lots of configured addresses. We were doing things like traversing the entire address less for each address removed, and flushing the entire netfilter conntrack table for every address as well. 8) Add and use SKB bulk free infrastructure, from Jesper Brouer. 9) Allow offloading u32 classifiers to hardware, and implement for ixgbe, from John Fastabend. 10) Allow configuring IRQ coalescing parameters on a per-queue basis, from Kan Liang. 11) Extend ethtool so that larger link mode masks can be supported. From David Decotigny. 12) Introduce devlink, which can be used to configure port link types (ethernet vs Infiniband, etc.), port splitting, and switch device level attributes as a whole. From Jiri Pirko. 13) Hardware offload support for flower classifiers, from Amir Vadai. 14) Add "Local Checksum Offload". Basically, for a tunneled packet the checksum of the outer header is 'constant' (because with the checksum field filled into the inner protocol header, the payload of the outer frame checksums to 'zero'), and we can take advantage of that in various ways. From Edward Cree" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits) bonding: fix bond_get_stats() net: bcmgenet: fix dma api length mismatch net/mlx4_core: Fix backward compatibility on VFs phy: mdio-thunder: Fix some Kconfig typos lan78xx: add ndo_get_stats64 lan78xx: handle statistics counter rollover RDS: TCP: Remove unused constant RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket net: smc911x: convert pxa dma to dmaengine team: remove duplicate set of flag IFF_MULTICAST bonding: remove duplicate set of flag IFF_MULTICAST net: fix a comment typo ethernet: micrel: fix some error codes ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it bpf, dst: add and use dst_tclassid helper bpf: make skb->tc_classid also readable net: mvneta: bm: clarify dependencies cls_bpf: reset class and reuse major in da ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c ldmvsw: Add ldmvsw.c driver code ...
2016-03-19Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge second patch-bomb from Andrew Morton: - a couple of hotfixes - the rest of MM - a new timer slack control in procfs - a couple of procfs fixes - a few misc things - some printk tweaks - lib/ updates, notably to radix-tree. - add my and Nick Piggin's old userspace radix-tree test harness to tools/testing/radix-tree/. Matthew said it was a godsend during the radix-tree work he did. - a few code-size improvements, switching to __always_inline where gcc screwed up. - partially implement character sets in sscanf * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits) sscanf: implement basic character sets lib/bug.c: use common WARN helper param: convert some "on"/"off" users to strtobool lib: add "on"/"off" support to kstrtobool lib: update single-char callers of strtobool() lib: move strtobool() to kstrtobool() include/linux/unaligned: force inlining of byteswap operations include/uapi/linux/byteorder, swab: force inlining of some byteswap operations include/asm-generic/atomic-long.h: force inlining of some atomic_long operations usb: common: convert to use match_string() helper ide: hpt366: convert to use match_string() helper ata: hpt366: convert to use match_string() helper power: ab8500: convert to use match_string() helper power: charger_manager: convert to use match_string() helper drm/edid: convert to use match_string() helper pinctrl: convert to use match_string() helper device property: convert to use match_string() helper lib/string: introduce match_string() helper radix-tree tests: add test for radix_tree_iter_next radix-tree tests: add regression3 test ...
2016-03-18Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: drivers/rtc: broken link fix drm/i915 Fix typos in i915_gem_fence.c Docs: fix missing word in REPORTING-BUGS lib+mm: fix few spelling mistakes MAINTAINERS: add git URL for APM driver treewide: Fix typo in printk
2016-03-18Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Here are the main arm64 updates for 4.6. There are some relatively intrusive changes to support KASLR, the reworking of the kernel virtual memory layout and initial page table creation. Summary: - Initial page table creation reworked to avoid breaking large block mappings (huge pages) into smaller ones. The ARM architecture requires break-before-make in such cases to avoid TLB conflicts but that's not always possible on live page tables - Kernel virtual memory layout: the kernel image is no longer linked to the bottom of the linear mapping (PAGE_OFFSET) but at the bottom of the vmalloc space, allowing the kernel to be loaded (nearly) anywhere in physical RAM - Kernel ASLR: position independent kernel Image and modules being randomly mapped in the vmalloc space with the randomness is provided by UEFI (efi_get_random_bytes() patches merged via the arm64 tree, acked by Matt Fleming) - Implement relative exception tables for arm64, required by KASLR (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c but actual x86 conversion to deferred to 4.7 because of the merge dependencies) - Support for the User Access Override feature of ARMv8.2: this allows uaccess functions (get_user etc.) to be implemented using LDTR/STTR instructions. Such instructions, when run by the kernel, perform unprivileged accesses adding an extra level of protection. The set_fs() macro is used to "upgrade" such instruction to privileged accesses via the UAO bit - Half-precision floating point support (part of ARMv8.2) - Optimisations for CPUs with or without a hardware prefetcher (using run-time code patching) - copy_page performance improvement to deal with 128 bytes at a time - Sanity checks on the CPU capabilities (via CPUID) to prevent incompatible secondary CPUs from being brought up (e.g. weird big.LITTLE configurations) - valid_user_regs() reworked for better sanity check of the sigcontext information (restored pstate information) - ACPI parking protocol implementation - CONFIG_DEBUG_RODATA enabled by default - VDSO code marked as read-only - DEBUG_PAGEALLOC support - ARCH_HAS_UBSAN_SANITIZE_ALL enabled - Erratum workaround Cavium ThunderX SoC - set_pte_at() fix for PROT_NONE mappings - Code clean-ups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (99 commits) arm64: kasan: Fix zero shadow mapping overriding kernel image shadow arm64: kasan: Use actual memory node when populating the kernel image shadow arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permission arm64: Fix misspellings in comments. arm64: efi: add missing frame pointer assignment arm64: make mrs_s prefixing implicit in read_cpuid arm64: enable CONFIG_DEBUG_RODATA by default arm64: Rework valid_user_regs arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly arm64: KVM: Move kvm_call_hyp back to its original localtion arm64: mm: treat memstart_addr as a signed quantity arm64: mm: list kernel sections in order arm64: lse: deal with clobbered IP registers after branch via PLT arm64: mm: dump: Use VA_START directly instead of private LOWEST_ADDR arm64: kconfig: add submenu for 8.2 architectural features arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot arm64: Add support for Half precision floating point arm64: Remove fixmap include fragility arm64: Add workaround for Cavium erratum 27456 arm64: mm: Mark .rodata as RO ...
2016-03-17sscanf: implement basic character setsJessica Yu
Implement basic character sets for the '%[' conversion specifier. The '%[' conversion specifier matches a nonempty sequence of characters from the specified set of accepted (or with '^', rejected) characters between the brackets. The substring matched is to be made up of characters in (or not in) the set. This is useful for matching substrings that are delimited by something other than spaces. This implementation differs from its glibc counterpart in the following ways: (1) No support for character ranges (e.g., 'a-z' or '0-9') (2) The hyphen '-' is not a special character (3) The closing bracket ']' cannot be matched (4) No support (yet) for discarding matching input ('%*[') The bitmap code is largely based upon sample code which was provided by Rasmus. The motivation for adding character set support to sscanf originally stemmed from the kernel livepatching project. An ongoing patchset utilizes new livepatch Elf symbol and section names to store important metadata livepatch needs to properly apply its patches. Such metadata is stored in these section and symbol names as substrings delimited by periods '.' and commas ','. For example, a livepatch symbol name might look like this: .klp.sym.vmlinux.printk,0 However, sscanf currently can only extract "substrings" delimited by whitespace using the "%s" specifier. Thus for the above symbol name, one cannot not use sscanf() to extract substrings "vmlinux" or "printk", for example. A number of discussions on the livepatch mailing list dealing with string parsing code for extracting these '.' and ',' delimited substrings eventually led to the conclusion that such code would be completely unnecessary if the kernel sscanf() supported character sets. Thus only a single sscanf() call would be necessary to extract these substrings. In addition, such an addition to sscanf() could benefit other areas of the kernel that might have a similar need in the future. [akpm@linux-foundation.org: 80-col tweaks] Signed-off-by: Jessica Yu <jeyu@redhat.com> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>