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2022-09-24debugfs: use DEFINE_SHOW_ATTRIBUTE to define debugfs_regset32_fopsChenXiaoSong
Use DEFINE_SHOW_ATTRIBUTE helper macro to simplify the code. Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com> Link: https://lore.kernel.org/r/20220923102554.2443452-1-chenxiaosong2@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-06debugfs: lockdown: Allow reading debugfs files that are not world readableMichal Suchanek
When the kernel is locked down the kernel allows reading only debugfs files with mode 444. Mode 400 is also valid but is not allowed. Make the 444 into a mask. Fixes: 5496197f9b08 ("debugfs: Restrict debugfs when the kernel is locked down") Signed-off-by: Michal Suchanek <msuchanek@suse.de> Link: https://lore.kernel.org/r/20220104170505.10248-1-msuchanek@suse.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-05debugfs: Return error during {full/open}_proxy_open() on rmmodSven Eckelmann
If a kernel module gets unloaded then it printed report about a leak before commit 275678e7a9be ("debugfs: Check module state before warning in {full/open}_proxy_open()"). An additional check was added in this commit to avoid this printing. But it was forgotten that the function must return an error in this case because it was not actually opened. As result, the systems started to crash or to hang when a module was unloaded while something was trying to open a file. Fixes: 275678e7a9be ("debugfs: Check module state before warning in {full/open}_proxy_open()") Cc: Taehee Yoo <ap420073@gmail.com> Reported-by: Mário Lopes <ml@simonwunderlich.de> Signed-off-by: Sven Eckelmann <sven@narfation.org> Link: https://lore.kernel.org/r/20210802162444.7848-1-sven@narfation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-14Merge tag 'v5.13-rc6' into driver-core-nextGreg Kroah-Hartman
We need the driver core fix in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-04debugfs: Fix debugfs_read_file_str()Dietmar Eggemann
Read the entire size of the buffer, including the trailing new line character. Discovered while reading the sched domain names of CPU0: before: cat /sys/kernel/debug/sched/domains/cpu0/domain*/name SMTMCDIE after: cat /sys/kernel/debug/sched/domains/cpu0/domain*/name SMT MC DIE Fixes: 9af0440ec86eb ("debugfs: Implement debugfs_create_str()") Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Link: https://lore.kernel.org/r/20210527091105.258457-1-dietmar.eggemann@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21debugfs: remove return value of debugfs_create_ulong()Greg Kroah-Hartman
No one checks the return value of debugfs_create_ulong(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20210521184340.1348539-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-21debugfs: remove return value of debugfs_create_bool()Greg Kroah-Hartman
No one checks the return value of debugfs_create_bool(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20210521184519.1356639-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14debugfs: only accept read attributes for blobsWolfram Sang
Blobs can only be read. So, keep only 'read' file attributes because the others will not work and only confuse users. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20210504131350.46586-1-wsa+renesas@sang-engineering.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-28Merge tag 'sched-core-2021-04-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - Clean up SCHED_DEBUG: move the decades old mess of sysctl, procfs and debugfs interfaces to a unified debugfs interface. - Signals: Allow caching one sigqueue object per task, to improve performance & latencies. - Improve newidle_balance() irq-off latencies on systems with a large number of CPU cgroups. - Improve energy-aware scheduling - Improve the PELT metrics for certain workloads - Reintroduce select_idle_smt() to improve load-balancing locality - but without the previous regressions - Add 'scheduler latency debugging': warn after long periods of pending need_resched. This is an opt-in feature that requires the enabling of the LATENCY_WARN scheduler feature, or the use of the resched_latency_warn_ms=xx boot parameter. - CPU hotplug fixes for HP-rollback, and for the 'fail' interface. Fix remaining balance_push() vs. hotplug holes/races - PSI fixes, plus allow /proc/pressure/ files to be written by CAP_SYS_RESOURCE tasks as well - Fix/improve various load-balancing corner cases vs. capacity margins - Fix sched topology on systems with NUMA diameter of 3 or above - Fix PF_KTHREAD vs to_kthread() race - Minor rseq optimizations - Misc cleanups, optimizations, fixes and smaller updates * tag 'sched-core-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (61 commits) cpumask/hotplug: Fix cpu_dying() state tracking kthread: Fix PF_KTHREAD vs to_kthread() race sched/debug: Fix cgroup_path[] serialization sched,psi: Handle potential task count underflow bugs more gracefully sched: Warn on long periods of pending need_resched sched/fair: Move update_nohz_stats() to the CONFIG_NO_HZ_COMMON block to simplify the code & fix an unused function warning sched/debug: Rename the sched_debug parameter to sched_verbose sched,fair: Alternative sched_slice() sched: Move /proc/sched_debug to debugfs sched,debug: Convert sysctl sched_domains to debugfs debugfs: Implement debugfs_create_str() sched,preempt: Move preempt_dynamic to debug.c sched: Move SCHED_DEBUG sysctl to debugfs sched: Don't make LATENCYTOP select SCHED_DEBUG sched: Remove sched_schedstats sysctl out from under SCHED_DEBUG sched/numa: Allow runtime enabling/disabling of NUMA balance without SCHED_DEBUG sched: Use cpu_dying() to fix balance_push vs hotplug-rollback cpumask: Introduce DYING mask cpumask: Make cpu_{online,possible,present,active}() inline rseq: Optimise rseq_get_rseq_cs() and clear_rseq_cs() ...
2021-04-16debugfs: Implement debugfs_create_str()Peter Zijlstra
Implement debugfs_create_str() to easily display names and such in debugfs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210412102001.415407080@infradead.org
2021-04-05debugfs: drop pointless nul-termination in debugfs_read_file_bool()Rasmus Villemoes
simple_read_from_buffer() doesn't care about any bytes in the buffer beyond "available". Making the buffer nul-terminated is therefore completely pointless. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20210326151411.732220-1-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30debugfs: remove return value of debugfs_create_devm_seqfile()Greg Kroah-Hartman
No one checks the return value of debugfs_create_devm_seqfile(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20201023131037.2500765-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04debugfs: Fix module state check conditionVladis Dronov
The '#ifdef MODULE' check in the original commit does not work as intended. The code under the check is not built at all if CONFIG_DEBUG_FS=y. Fix this by using a correct check. Fixes: 275678e7a9be ("debugfs: Check module state before warning in {full/open}_proxy_open()") Signed-off-by: Vladis Dronov <vdronov@redhat.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200811150129.53343-1-vdronov@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan. 2) Support UDP segmentation in code TSO code, from Eric Dumazet. 3) Allow flashing different flash images in cxgb4 driver, from Vishal Kulkarni. 4) Add drop frames counter and flow status to tc flower offloading, from Po Liu. 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni. 6) Various new indirect call avoidance, from Eric Dumazet and Brian Vazquez. 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from Yonghong Song. 8) Support querying and setting hardware address of a port function via devlink, use this in mlx5, from Parav Pandit. 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson. 10) Switch qca8k driver over to phylink, from Jonathan McDowell. 11) In bpftool, show list of processes holding BPF FD references to maps, programs, links, and btf objects. From Andrii Nakryiko. 12) Several conversions over to generic power management, from Vaibhav Gupta. 13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry Yakunin. 14) Various https url conversions, from Alexander A. Klimov. 15) Timestamping and PHC support for mscc PHY driver, from Antoine Tenart. 16) Support bpf iterating over tcp and udp sockets, from Yonghong Song. 17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov. 18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan. 19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several drivers. From Luc Van Oostenryck. 20) XDP support for xen-netfront, from Denis Kirjanov. 21) Support receive buffer autotuning in MPTCP, from Florian Westphal. 22) Support EF100 chip in sfc driver, from Edward Cree. 23) Add XDP support to mvpp2 driver, from Matteo Croce. 24) Support MPTCP in sock_diag, from Paolo Abeni. 25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic infrastructure, from Jakub Kicinski. 26) Several pci_ --> dma_ API conversions, from Christophe JAILLET. 27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel. 28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki. 29) Refactor a lot of networking socket option handling code in order to avoid set_fs() calls, from Christoph Hellwig. 30) Add rfc4884 support to icmp code, from Willem de Bruijn. 31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei. 32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin. 33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin. 34) Support TCP syncookies in MPTCP, from Flowian Westphal. 35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano Brivio. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits) net: thunderx: initialize VF's mailbox mutex before first usage usb: hso: remove bogus check for EINPROGRESS usb: hso: no complaint about kmalloc failure hso: fix bailout in error case of probe ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM selftests/net: relax cpu affinity requirement in msg_zerocopy test mptcp: be careful on subflow creation selftests: rtnetlink: make kci_test_encap() return sub-test result selftests: rtnetlink: correct the final return value for the test net: dsa: sja1105: use detected device id instead of DT one on mismatch tipc: set ub->ifindex for local ipv6 address ipv6: add ipv6_dev_find() net: openvswitch: silence suspicious RCU usage warning Revert "vxlan: fix tos value before xmit" ptp: only allow phase values lower than 1 period farsync: switch from 'pci_' to 'dma_' API wan: wanxl: switch from 'pci_' to 'dma_' API hv_netvsc: do not use VF device if link is down dpaa2-eth: Fix passing zero to 'PTR_ERR' warning net: macb: Properly handle phylink on at91sam9x ...
2020-07-10debugfs: make sure we can remove u32_array files cleanlyJakub Kicinski
debugfs_create_u32_array() allocates a small structure to wrap the data and size information about the array. If users ever try to remove the file this leads to a leak since nothing ever frees this wrapper. That said there are no upstream users of debugfs_create_u32_array() that'd remove a u32 array file (we only have one u32 array user in CMA), so there is no real bug here. Make callers pass a wrapper they allocated. This way the lifetime management of the wrapper is on the caller, and we can avoid the potential leak in debugfs. CC: Chucheng Luo <luochucheng@vivo.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-10debugfs: file: Remove unnecessary cast in kfree()Xu Wang
Remove unnecassary casts in the argument to kfree. Signed-off-by: Xu Wang <vulab@iscas.ac.cn> Link: https://lore.kernel.org/r/20200709054033.30148-1-vulab@iscas.ac.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-17debugfs: remove return value of debugfs_create_u32()Greg Kroah-Hartman
No one checks the return value of debugfs_create_u32(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20200416145448.GA1380878@kroah.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-01Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Fix out-of-sync IVs in self-test for IPsec AEAD algorithms Algorithms: - Use formally verified implementation of x86/curve25519 Drivers: - Enhance hwrng support in caam - Use crypto_engine for skcipher/aead/rsa/hash in caam - Add Xilinx AES driver - Add uacce driver - Register zip engine to uacce in hisilicon - Add support for OCTEON TX CPT engine in marvell" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (162 commits) crypto: af_alg - bool type cosmetics crypto: arm[64]/poly1305 - add artifact to .gitignore files crypto: caam - limit single JD RNG output to maximum of 16 bytes crypto: caam - enable prediction resistance in HRWNG bus: fsl-mc: add api to retrieve mc version crypto: caam - invalidate entropy register during RNG initialization crypto: caam - check if RNG job failed crypto: caam - simplify RNG implementation crypto: caam - drop global context pointer and init_done crypto: caam - use struct hwrng's .init for initialization crypto: caam - allocate RNG instantiation descriptor with GFP_DMA crypto: ccree - remove duplicated include from cc_aead.c crypto: chelsio - remove set but not used variable 'adap' crypto: marvell - enable OcteonTX cpt options for build crypto: marvell - add the Virtual Function driver for CPT crypto: marvell - add support for OCTEON TX CPT engine crypto: marvell - create common Kconfig and Makefile for Marvell crypto: arm/neon - memzero_explicit aes-cbc key crypto: bcm - Use scnprintf() for avoiding potential buffer overflow crypto: atmel-i2c - Fix wakeup fail ...
2020-03-18debugfs: Check module state before warning in {full/open}_proxy_open()Taehee Yoo
When the module is being removed, the module state is set to MODULE_STATE_GOING. At this point, try_module_get() fails. And when {full/open}_proxy_open() is being called, it calls try_module_get() to try to hold module reference count. If it fails, it warns about the possibility of debugfs file leak. If {full/open}_proxy_open() is called while the module is being removed, it fails to hold the module. So, It warns about debugfs file leak. But it is not the debugfs file leak case. So, this patch just adds module state checking routine in the {full/open}_proxy_open(). Test commands: #SHELL1 while : do modprobe netdevsim echo 1 > /sys/bus/netdevsim/new_device modprobe -rv netdevsim done #SHELL2 while : do cat /sys/kernel/debug/netdevsim/netdevsim1/ports/0/ipsec done Splat looks like: [ 298.766738][T14664] debugfs file owner did not clean up at exit: ipsec [ 298.766766][T14664] WARNING: CPU: 2 PID: 14664 at fs/debugfs/file.c:312 full_proxy_open+0x10f/0x650 [ 298.768595][T14664] Modules linked in: netdevsim(-) openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 n][ 298.771343][T14664] CPU: 2 PID: 14664 Comm: cat Tainted: G W 5.5.0+ #1 [ 298.772373][T14664] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 298.773545][T14664] RIP: 0010:full_proxy_open+0x10f/0x650 [ 298.774247][T14664] Code: 48 c1 ea 03 80 3c 02 00 0f 85 c1 04 00 00 49 8b 3c 24 e8 e4 b5 78 ff 84 c0 75 2d 4c 89 ee 48 [ 298.776782][T14664] RSP: 0018:ffff88805b7df9b8 EFLAGS: 00010282[ 298.777583][T14664] RAX: dffffc0000000008 RBX: ffff8880511725c0 RCX: 0000000000000000 [ 298.778610][T14664] RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffff8880540c5c14 [ 298.779637][T14664] RBP: 0000000000000000 R08: fffffbfff15235ad R09: 0000000000000000 [ 298.780664][T14664] R10: 0000000000000001 R11: 0000000000000000 R12: ffffffffc06b5000 [ 298.781702][T14664] R13: ffff88804c234a88 R14: ffff88804c22dd00 R15: ffffffff8a1b5660 [ 298.782722][T14664] FS: 00007fafa13a8540(0000) GS:ffff88806c800000(0000) knlGS:0000000000000000 [ 298.783845][T14664] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 298.784672][T14664] CR2: 00007fafa0e9cd10 CR3: 000000004b286005 CR4: 00000000000606e0 [ 298.785739][T14664] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 298.786769][T14664] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 298.787785][T14664] Call Trace: [ 298.788237][T14664] do_dentry_open+0x63c/0xf50 [ 298.788872][T14664] ? open_proxy_open+0x270/0x270 [ 298.789524][T14664] ? __x64_sys_fchdir+0x180/0x180 [ 298.790169][T14664] ? inode_permission+0x65/0x390 [ 298.790832][T14664] path_openat+0xc45/0x2680 [ 298.791425][T14664] ? save_stack+0x69/0x80 [ 298.791988][T14664] ? save_stack+0x19/0x80 [ 298.792544][T14664] ? path_mountpoint+0x2e0/0x2e0 [ 298.793233][T14664] ? check_chain_key+0x236/0x5d0 [ 298.793910][T14664] ? sched_clock_cpu+0x18/0x170 [ 298.794527][T14664] ? find_held_lock+0x39/0x1d0 [ 298.795153][T14664] do_filp_open+0x16a/0x260 [ ... ] Fixes: 9fd4dcece43a ("debugfs: prevent access to possibly dead file_operations at file open") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Taehee Yoo <ap420073@gmail.com> Link: https://lore.kernel.org/r/20200218043150.29447-1-ap420073@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-22debugfs: regset32: Add Runtime PM supportGeert Uytterhoeven
Hardware registers of devices under control of power management cannot be accessed at all times. If such a device is suspended, register accesses may lead to undefined behavior, like reading bogus values, or causing exceptions or system lock-ups. Extend struct debugfs_regset32 with an optional field to let device drivers specify the device the registers in the set belong to. This allows debugfs_show_regset32() to make sure the device is resumed while its registers are being read. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-02-10debugfs: remove return value of debugfs_create_regset32()Greg Kroah-Hartman
No one checks the return value of debugfs_create_regset32(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20191122104453.GA2017837@kroah.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14debugfs: Return -EPERM when locked downEric Snowberg
When lockdown is enabled, debugfs_is_locked_down returns 1. It will then trigger the following: WARNING: CPU: 48 PID: 3747 CPU: 48 PID: 3743 Comm: bash Not tainted 5.4.0-1946.x86_64 #1 Hardware name: Oracle Corporation ORACLE SERVER X7-2/ASM, MB, X7-2, BIOS 41060400 05/20/2019 RIP: 0010:do_dentry_open+0x343/0x3a0 Code: 00 40 08 00 45 31 ff 48 c7 43 28 40 5b e7 89 e9 02 ff ff ff 48 8b 53 28 4c 8b 72 70 4d 85 f6 0f 84 10 fe ff ff e9 f5 fd ff ff <0f> 0b 41 bf ea ff ff ff e9 3b ff ff ff 41 bf e6 ff ff ff e9 b4 fe RSP: 0018:ffffb8740dde7ca0 EFLAGS: 00010202 RAX: ffffffff89e88a40 RBX: ffff928c8e6b6f00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff928dbfd97778 RDI: ffff9285cff685c0 RBP: ffffb8740dde7cc8 R08: 0000000000000821 R09: 0000000000000030 R10: 0000000000000057 R11: ffffb8740dde7a98 R12: ffff926ec781c900 R13: ffff928c8e6b6f10 R14: ffffffff8936e190 R15: 0000000000000001 FS: 00007f45f6777740(0000) GS:ffff928dbfd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff95e0d5d8 CR3: 0000001ece562006 CR4: 00000000007606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: vfs_open+0x2d/0x30 path_openat+0x2d4/0x1680 ? tty_mode_ioctl+0x298/0x4c0 do_filp_open+0x93/0x100 ? strncpy_from_user+0x57/0x1b0 ? __alloc_fd+0x46/0x150 do_sys_open+0x182/0x230 __x64_sys_openat+0x20/0x30 do_syscall_64+0x60/0x1b0 entry_SYSCALL_64_after_hwframe+0x170/0x1d5 RIP: 0033:0x7f45f5e5ce02 Code: 25 00 00 41 00 3d 00 00 41 00 74 4c 48 8d 05 25 59 2d 00 8b 00 85 c0 75 6d 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 0f 87 a2 00 00 00 48 8b 4c 24 28 64 48 33 0c 25 RSP: 002b:00007fff95e0d2e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000561178c069b0 RCX: 00007f45f5e5ce02 RDX: 0000000000000241 RSI: 0000561178c08800 RDI: 00000000ffffff9c RBP: 00007fff95e0d3e0 R08: 0000000000000020 R09: 0000000000000005 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000001 R15: 0000561178c08800 Change the return type to int and return -EPERM when lockdown is enabled to remove the warning above. Also rename debugfs_is_locked_down to debugfs_locked_down to make it sound less like it returns a boolean. Fixes: 5496197f9b08 ("debugfs: Restrict debugfs when the kernel is locked down") Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: stable <stable@vger.kernel.org> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/r/20191207161603.35907-1-eric.snowberg@oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-06debugfs: Fix warnings when building documentationDaniel W. S. Almeida
Fix the following warnings: fs/debugfs/inode.c:423: WARNING: Inline literal start-string without end-string. fs/debugfs/inode.c:502: WARNING: Inline literal start-string without end-string. fs/debugfs/inode.c:534: WARNING: Inline literal start-string without end-string. fs/debugfs/inode.c:627: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:496: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:502: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:581: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:587: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:846: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:852: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:899: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:905: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:1091: WARNING: Inline literal start-string without end-string. fs/debugfs/file.c:1097: WARNING: Inline literal start-string without end-string By replacing %ERR_PTR with ERR_PTR. Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com> Link: https://lore.kernel.org/r/20191227010035.854913-1-dwlsalmeida@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-03debugfs: remove return value of debugfs_create_atomic_t()Greg Kroah-Hartman
No one checks the return value of debugfs_create_atomic_t(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20191016130332.GA28240@kroah.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-02debugfs: remove return value of debugfs_create_x8()Greg Kroah-Hartman
No one checks the return value of debugfs_create_x8(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20191011132931.1186197-5-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-16debugfs: remove return value of debugfs_create_x64()Greg Kroah-Hartman
No one checks the return value of debugfs_create_x64(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20191011132931.1186197-8-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-16debugfs: remove return value of debugfs_create_x32()Greg Kroah-Hartman
No one checks the return value of debugfs_create_x32(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20191011132931.1186197-7-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-16debugfs: remove return value of debugfs_create_x16()Greg Kroah-Hartman
No one checks the return value of debugfs_create_x16(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Link: https://lore.kernel.org/r/20191011132931.1186197-6-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-14debugfs: remove return value of debugfs_create_size_t()Greg Kroah-Hartman
No one checks the return value of debugfs_create_size_t(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20191011132931.1186197-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-14debugfs: remove return value of debugfs_create_u64()Greg Kroah-Hartman
No one checks the return value of debugfs_create_u64(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20191011132931.1186197-3-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-14debugfs: remove return value of debugfs_create_u16()Greg Kroah-Hartman
No one checks the return value of debugfs_create_u16(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20191011132931.1186197-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-14debugfs: remove return value of debugfs_create_u8()Greg Kroah-Hartman
No one checks the return value of debugfs_create_u8(), as it's not needed, so make the return value void, so that no one tries to do so in the future. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20191011132931.1186197-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-28Merge branch 'next-lockdown' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull kernel lockdown mode from James Morris: "This is the latest iteration of the kernel lockdown patchset, from Matthew Garrett, David Howells and others. From the original description: This patchset introduces an optional kernel lockdown feature, intended to strengthen the boundary between UID 0 and the kernel. When enabled, various pieces of kernel functionality are restricted. Applications that rely on low-level access to either hardware or the kernel may cease working as a result - therefore this should not be enabled without appropriate evaluation beforehand. The majority of mainstream distributions have been carrying variants of this patchset for many years now, so there's value in providing a doesn't meet every distribution requirement, but gets us much closer to not requiring external patches. There are two major changes since this was last proposed for mainline: - Separating lockdown from EFI secure boot. Background discussion is covered here: https://lwn.net/Articles/751061/ - Implementation as an LSM, with a default stackable lockdown LSM module. This allows the lockdown feature to be policy-driven, rather than encoding an implicit policy within the mechanism. The new locked_down LSM hook is provided to allow LSMs to make a policy decision around whether kernel functionality that would allow tampering with or examining the runtime state of the kernel should be permitted. The included lockdown LSM provides an implementation with a simple policy intended for general purpose use. This policy provides a coarse level of granularity, controllable via the kernel command line: lockdown={integrity|confidentiality} Enable the kernel lockdown feature. If set to integrity, kernel features that allow userland to modify the running kernel are disabled. If set to confidentiality, kernel features that allow userland to extract confidential information from the kernel are also disabled. This may also be controlled via /sys/kernel/security/lockdown and overriden by kernel configuration. New or existing LSMs may implement finer-grained controls of the lockdown features. Refer to the lockdown_reason documentation in include/linux/security.h for details. The lockdown feature has had signficant design feedback and review across many subsystems. This code has been in linux-next for some weeks, with a few fixes applied along the way. Stephen Rothwell noted that commit 9d1f8be5cf42 ("bpf: Restrict bpf when kernel lockdown is in confidentiality mode") is missing a Signed-off-by from its author. Matthew responded that he is providing this under category (c) of the DCO" * 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits) kexec: Fix file verification on S390 security: constify some arrays in lockdown LSM lockdown: Print current->comm in restriction messages efi: Restrict efivar_ssdt_load when the kernel is locked down tracefs: Restrict tracefs when the kernel is locked down debugfs: Restrict debugfs when the kernel is locked down kexec: Allow kexec_file() with appropriate IMA policy when locked down lockdown: Lock down perf when in confidentiality mode bpf: Restrict bpf when kernel lockdown is in confidentiality mode lockdown: Lock down tracing and perf kprobes when in confidentiality mode lockdown: Lock down /proc/kcore x86/mmiotrace: Lock down the testmmiotrace module lockdown: Lock down module params that specify hardware parameters (eg. ioport) lockdown: Lock down TIOCSSERIAL lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down acpi: Disable ACPI table override if the kernel is locked down acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down ACPI: Limit access to custom_method when the kernel is locked down x86/msr: Restrict MSR access when the kernel is locked down x86: Lock down IO port access when the kernel is locked down ...
2019-08-19debugfs: Restrict debugfs when the kernel is locked downDavid Howells
Disallow opening of debugfs files that might be used to muck around when the kernel is locked down as various drivers give raw access to hardware through debugfs. Given the effort of auditing all 2000 or so files and manually fixing each one as necessary, I've chosen to apply a heuristic instead. The following changes are made: (1) chmod and chown are disallowed on debugfs objects (though the root dir can be modified by mount and remount, but I'm not worried about that). (2) When the kernel is locked down, only files with the following criteria are permitted to be opened: - The file must have mode 00444 - The file must not have ioctl methods - The file must not have mmap (3) When the kernel is locked down, files may only be opened for reading. Normal device interaction should be done through configfs, sysfs or a miscdev, not debugfs. Note that this makes it unnecessary to specifically lock down show_dsts(), show_devs() and show_call() in the asus-wmi driver. I would actually prefer to lock down all files by default and have the the files unlocked by the creator. This is tricky to manage correctly, though, as there are 19 creation functions and ~1600 call sites (some of them in loops scanning tables). Signed-off-by: David Howells <dhowells@redhat.com> cc: Andy Shevchenko <andy.shevchenko@gmail.com> cc: acpi4asus-user@lists.sourceforge.net cc: platform-driver-x86@vger.kernel.org cc: Matthew Garrett <mjg59@srcf.ucam.org> cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Matthew Garrett <matthewgarrett@google.com> Signed-off-by: James Morris <jmorris@namei.org>
2019-06-03debugfs: make debugfs_create_u32_array() return voidGreg Kroah-Hartman
The single user of debugfs_create_u32_array() does not care about the return value of it, so make it return void as there is no need to do anything with the return value. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25debugfs: update documented return values of debugfs helpersRonald Tschalär
Since commit ff9fb72bc077 ("debugfs: return error values, not NULL") these helper functions do not return NULL anymore (with the exception of debugfs_create_u32_array()). Fixes: ff9fb72bc077 ("debugfs: return error values, not NULL") Signed-off-by: Ronald Tschalär <ronald@innovation.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14debugfs: Re-use kstrtobool_from_user()Andy Shevchenko
Re-use kstrtobool_from_user() instead of open coded variant. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-11vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds
This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-01use linux/poll.h instead of asm/poll.hAl Viro
The only place that has any business including asm/poll.h is linux/poll.h. Fortunately, asm/poll.h had only been included in 3 places beyond that one, and all of them are trivial to switch to using linux/poll.h. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27fs: annotate ->poll() instancesAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27anntotate the places where ->poll() return values goAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-07debugfs: Remove redundant license textGreg Kroah-Hartman
Now that the SPDX tag is in all debugfs files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: add SPDX identifiers to all debugfs filesGreg Kroah-Hartman
It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the debugfs files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: defer debugfs_fsdata allocation to first usageNicolai Stange
Currently, __debugfs_create_file allocates one struct debugfs_fsdata instance for every file created. However, there are potentially many debugfs file around, most of which are never touched by userspace. Thus, defer the allocations to the first usage, i.e. to the first debugfs_file_get(). A dentry's ->d_fsdata starts out to point to the "real", user provided fops. After a debugfs_fsdata instance has been allocated (and the real fops pointer has been moved over into its ->real_fops member), ->d_fsdata is changed to point to it from then on. The two cases are distinguished by setting BIT(0) for the real fops case. struct debugfs_fsdata's foremost purpose is to track active users and to make debugfs_remove() block until they are done. Since no debugfs_fsdata instance means no active users, make debugfs_remove() return immediately in this case. Take care of possible races between debugfs_file_get() and debugfs_remove(): either debugfs_remove() must see a debugfs_fsdata instance and thus wait for possible active users or debugfs_file_get() must see a dead dentry and return immediately. Make a dentry's ->d_release(), i.e. debugfs_release_dentry(), check whether ->d_fsdata is actually a debugfs_fsdata instance before kfree()ing it. Similarly, make debugfs_real_fops() check whether ->d_fsdata is actually a debugfs_fsdata instance before returning it, otherwise emit a warning. The set of possible error codes returned from debugfs_file_get() has grown from -EIO to -EIO and -ENOMEM. Make open_proxy_open() and full_proxy_open() pass the -ENOMEM onwards to their callers. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: call debugfs_real_fops() only after debugfs_file_get()Nicolai Stange
The current implementation of debugfs_real_fops() relies on a debugfs_fsdata instance to be installed at ->d_fsdata. With future patches introducing lazy allocation of these, this requirement will be guaranteed to be fullfilled only inbetween a debugfs_file_get()/debugfs_file_put() pair. The full proxies' fops implemented by debugfs happen to be the only offenders. Fix them up by moving their debugfs_real_fops() calls past those to debugfs_file_get(). full_proxy_release() is special as it doesn't invoke debugfs_file_get() at all. Leave it alone for now. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: purge obsolete SRCU based removal protectionNicolai Stange
Purge the SRCU based file removal race protection in favour of the new, refcount based debugfs_file_get()/debugfs_file_put() API. Fixes: 49d200deaa68 ("debugfs: prevent access to removed files' private data") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: convert to debugfs_file_get() and -put()Nicolai Stange
Convert all calls to the now obsolete debugfs_use_file_start() and debugfs_use_file_finish() from the debugfs core itself to the new debugfs_file_get() and debugfs_file_put() API. Fixes: 49d200deaa68 ("debugfs: prevent access to removed files' private data") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: debugfs_real_fops(): drop __must_hold sparse annotationNicolai Stange
Currently, debugfs_real_fops() is annotated with a __must_hold(&debugfs_srcu) sparse annotation. With the conversion of the SRCU based protection of users against concurrent file removals to a per-file refcount based scheme, this becomes wrong. Drop this annotation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: implement per-file removal protectionNicolai Stange
Since commit 49d200deaa68 ("debugfs: prevent access to removed files' private data"), accesses to a file's private data are protected from concurrent removal by covering all file_operations with a SRCU read section and sychronizing with those before returning from debugfs_remove() by means of synchronize_srcu(). As pointed out by Johannes Berg, there are debugfs files with forever blocking file_operations. Their corresponding SRCU read side sections would block any debugfs_remove() forever as well, even unrelated ones. This results in a livelock. Because a remover can't cancel any indefinite blocking within foreign files, this is a problem. Resolve this by introducing support for more granular protection on a per-file basis. This is implemented by introducing an 'active_users' refcount_t to the per-file struct debugfs_fsdata state. At file creation time, it is set to one and a debugfs_remove() will drop that initial reference. The new debugfs_file_get() and debugfs_file_put(), intended to be used in place of former debugfs_use_file_start() and debugfs_use_file_finish(), increment and decrement it respectively. Once the count drops to zero, debugfs_file_put() will signal a completion which is possibly being waited for from debugfs_remove(). Thus, as long as there is a debugfs_file_get() not yet matched by a corresponding debugfs_file_put() around, debugfs_remove() will block. Actual users of debugfs_use_file_start() and -finish() will get converted to the new debugfs_file_get() and debugfs_file_put() by followup patches. Fixes: 49d200deaa68 ("debugfs: prevent access to removed files' private data") Reported-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07debugfs: add support for more elaborate ->d_fsdataNicolai Stange
Currently, the user provided fops, "real_fops", are stored directly into ->d_fsdata. In order to be able to store more per-file state and thus prepare for more granular file removal protection, wrap the real_fops into a dynamically allocated container struct, debugfs_fsdata. A struct debugfs_fsdata gets allocated at file creation and freed from the newly intoduced ->d_release(). Finally, move the implementation of debugfs_real_fops() out of the public debugfs header such that struct debugfs_fsdata's declaration can be kept private. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>