- Feb 14, 2020
-
-
Jan Kara authored
DIR_INDEX has been introduced as a compat ext4 feature. That means that even kernels / tools that don't understand the feature may modify the filesystem. This works because for kernels not understanding indexed dir format, internal htree nodes appear just as empty directory entries. Index dir aware kernels then check the htree structure is still consistent before using the data. This all worked reasonably well until metadata checksums were introduced. The problem is that these effectively made DIR_INDEX only ro-compatible because internal htree nodes store checksums in a different place than normal directory blocks. Thus any modification ignorant to DIR_INDEX (or just clearing EXT4_INDEX_FL from the inode) will effectively cause checksum mismatch and trigger kernel errors. So we have to be more careful when dealing with indexed directories on filesystems with checksumming enabled. 1) We just disallow loading any directory inodes with EXT4_INDEX_FL when DIR_INDEX is not enabled. This is harsh but it should be very rare (it means someone disabled DIR_INDEX on existing filesystem and didn't run e2fsck), e2fsck can fix the problem, and we don't want to answer the difficult question: "Should we rather corrupt the directory more or should we ignore that DIR_INDEX feature is not set?" 2) When we find out htree structure is corrupted (but the filesystem and the directory should in support htrees), we continue just ignoring htree information for reading but we refuse to add new entries to the directory to avoid corrupting it more. Link: https://lore.kernel.org/r/20200210144316.22081-1-jack@suse.cz Fixes: dbe89444 ("ext4: Calculate and verify checksums for htree nodes") Reviewed-by:
Andreas Dilger <adilger@dilger.ca> Signed-off-by:
Jan Kara <jack@suse.cz> Signed-off-by:
Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
-
Theodore Ts'o authored
A recent commit, 9803387c ("ext4: validate the debug_want_extra_isize mount option at parse time"), moved mount-time checks around. One of those changes moved the inode size check before the blocksize variable was set to the blocksize of the file system. After 9803387c was set to the minimum allowable blocksize, which in practice on most systems would be 1024 bytes. This cuased file systems with inode sizes larger than 1024 bytes to be rejected with a message: EXT4-fs (sdXX): unsupported inode size: 4096 Fixes: 9803387c ("ext4: validate the debug_want_extra_isize mount option at parse time") Link: https://lore.kernel.org/r/20200206225252.GA3673@mit.edu Reported-by:
Herbert Poetzl <herbert@13thfloor.at> Signed-off-by:
Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
-
Jan Kara authored
Coverity reports that conditions checking quota limits in ext4_statfs() contain dead code. Indeed it is right and current conditions can be simplified. Link: https://lore.kernel.org/r/20200130111148.10766-1-jack@suse.cz Reported-by:
Coverity <scan-admin@coverity.com> Signed-off-by:
Jan Kara <jack@suse.cz> Signed-off-by:
Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
-
Andreas Dilger authored
Don't assume that the mmp_nodename and mmp_bdevname strings are NUL terminated, since they are filled in by snprintf(), which is not guaranteed to do so. Link: https://lore.kernel.org/r/1580076215-1048-1-git-send-email-adilger@dilger.ca Signed-off-by:
Andreas Dilger <adilger@dilger.ca> Signed-off-by:
Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
-
- Jan 31, 2020
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4Linus Torvalds authored
Pull ext4 updates from Ted Ts'o: "This merge window, we've added some performance improvements in how we handle inode locking in the read/write paths, and improving the performance of Direct I/O overwrites. We also now record the error code which caused the first and most recent ext4_error() report in the superblock, to make it easier to root cause problems in production systems. There are also many of the usual cleanups and miscellaneous bug fixes" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (49 commits) jbd2: clean __jbd2_journal_abort_hard() and __journal_abort_soft() jbd2: make sure ESHUTDOWN to be recorded in the journal superblock ext4, jbd2: ensure panic when aborting with zero errno jbd2: switch to use jbd2_journal_abort() when failed to submit the commit record jbd2_seq_info_next should increase position index jbd2: remove pointless assertion in __journal_remove_journal_head ext4,jbd2: fix comment and code style jbd2: delete the duplicated words in the comments ext4: fix extent_status trace points ext4: fix symbolic enum printing in trace output ext4: choose hardlimit when softlimit is larger than hardlimit in ext4_statfs_project() ext4: fix race conditions in ->d_compare() and ->d_hash() ext4: make dioread_nolock the default ext4: fix extent_status fragmentation for plain files jbd2: clear JBD2_ABORT flag before journal_reset to update log tail info when load journal ext4: drop ext4_kvmalloc() ext4: Add EXT4_IOC_FSGETXATTR/EXT4_IOC_FSSETXATTR to compat_ioctl ext4: remove unused macro MPAGE_DA_EXTENT_TAIL ext4: add missing braces in ext4_ext_drop_refs() ext4: fix some nonstandard indentation in extents.c ...
-
git://anongit.freedesktop.org/drm/drmLinus Torvalds authored
Pull drm updates from Davbe Airlie: "This is the main pull request for graphics for 5.6. Usual selection of changes all over. I've got one outstanding vmwgfx pull that touches mm so kept it separate until after all of this lands. I'll try and get it to you soon after this, but it might be early next week (nothing wrong with code, just my schedule is messy) This also hits a lot of fbdev drivers with some cleanups. Other notables: - vulkan timeline semaphore support added to syncobjs - nouveau turing secureboot/graphics support - Displayport MST display stream compression support Detailed summary: uapi: - dma-buf heaps added (and fixed) - command line add support for panel oreientation - command line allow overriding penguin count drm: - mipi dsi definition updates - lockdep annotations for dma_resv - remove dma-buf kmap/kunmap support - constify fb_ops in all fbdev drivers - MST fix for daisy chained hotplug- - CTA-861-G modes with VIC >= 193 added - fix drm_panel_of_backlight export - LVDS decoder support - more device based logging support - scanline alighment for dumb buffers - MST DSC helpers scheduler: - documentation fixes - job distribution improvements panel: - Logic PD type 28 panel support - Jimax8729d MIPI-DSI - igenic JZ4770 - generic DSI devicetree bindings - sony acx424AKP panel - Leadtek LTK500HD1829 - xinpeng XPP055C272 - AUO B116XAK01 - GiantPlus GPM940B0 - BOE NV140FHM-N49 - Satoz SAT050AT40H12R2 - Sharp LS020B1DD01D panels. ttm: - use blocking WW lock i915: - hw/uapi state separation - Lock annotation improvements - selftest improvements - ICL/TGL DSI VDSC support - VBT parsing improvments - Display refactoring - DSI updates + fixes - HDCP 2.2 for CFL - CML PCI ID fixes - GLK+ fbc fix - PSR fixes - GEN/GT refactor improvments - DP MST fixes - switch context id alloc to xarray - workaround updates - LMEM debugfs support - tiled monitor fixes - ICL+ clock gating programming removed - DP MST disable sequence fixed - LMEM discontiguous object maps - prefaulting for discontiguous objects - use LMEM for dumb buffers if possible - add LMEM mmap support amdgpu: - enable sync object timelines for vulkan - MST atomic routines - enable MST DSC support - add DMCUB display microengine support - DC OEM i2c support - Renoir DC fixes - Initial HDCP 2.x support - BACO support for Arcturus - Use BACO for runtime PM power save - gfxoff on navi10 - gfx10 golden updates and fixes - DCN support on POWER - GFXOFF for raven1 refresh - MM engine idle handlers cleanup - 10bpc EDP panel fixes - renoir watermark fixes - SR-IOV fixes - Arcturus VCN fixes - GDDR6 training fixes - freesync fixes - Pollock support amdkfd: - unify more codepath with amdgpu - use KIQ to setup HIQ rather than MMIO radeon: - fix vma fault handler race - PPC DMA fix - register check fixes for r100/r200 nouveau: - mmap_sem vs dma_resv fix - rewrite the ACR secure boot code for Turing - TU10x graphics engine support (TU11x pending) - Page kind mapping for turing - 10-bit LUT support - GP10B Tegra fixes - HD audio regression fix hisilicon/hibmc: - use generic fbdev code and helpers rockchip: - dsi/px30 support virtio: - fb damage support - static some functions vc4: - use dma_resv lock wrappers msm: - use dma_resv lock wrappers - sc7180 display + DSI support - a618 support - UBWC support improvements vmwgfx: - updates + new logging uapi exynos: - enable/disable callback cleanups etnaviv: - use dma_resv lock wrappers atmel-hlcdc: - clock fixes mediatek: - cmdq support - non-smooth cursor fixes - ctm property support sun4i: - suspend support - A64 mipi dsi support rcar-du: - Color management module support - LVDS encoder dual-link support - R8A77980 support analogic: - add support for an6345 ast: - atomic modeset support - primary plane garbage fix arcgpu: - fixes for fourcc handling tegra: - minor fixes and improvments mcde: - vblank support meson: - OSD1 plane AFBC commit gma500: - add pageflip support - reomve global drm_dev komeda: - tweak debugfs output - d32 support - runtime PM suppotr udl: - use generic shmem helpers - cleanup and fixes" * tag 'drm-next-2020-01-30' of git://anongit.freedesktop.org/drm/drm: (1998 commits) drm/nouveau/fb/gp102-: allow module to load even when scrubber binary is missing drm/nouveau/acr: return error when registering LSF if ACR not supported drm/nouveau/disp/gv100-: not all channel types support reporting error codes drm/nouveau/disp/nv50-: prevent oops when no channel method map provided drm/nouveau: support synchronous pushbuf submission drm/nouveau: signal pending fences when channel has been killed drm/nouveau: reject attempts to submit to dead channels drm/nouveau: zero vma pointer even if we only unreference it rather than free drm/nouveau: Add HD-audio component notifier support drm/nouveau: fix build error without CONFIG_IOMMU_API drm/nouveau/kms/nv04: remove set but not used variable 'width' drm/nouveau/kms/nv50: remove set but not unused variable 'nv_connector' drm/nouveau/mmu: fix comptag memory leak drm/nouveau/gr/gp10b: Use gp100_grctx and gp100_gr_zbc drm/nouveau/pmu/gm20b,gp10b: Fix Falcon bootstrapping drm/exynos: Rename Exynos to lowercase drm/exynos: change callback names drm/mst: Don't do atomic checks over disabled managers drm/amdgpu: add the lost mutex_init back drm/amd/display: skip opp blank or unblank if test pattern enabled ...
-
- Jan 30, 2020
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supplyLinus Torvalds authored
Pull power supply and reset updates from Sebastian Reichel: "Core: - Add battery internal resistance temperature table support Drivers: - sc27xx: Optimize the battery resistance with measuring temperature - max17042-battery: Add MAX17055 support - bq25890-charger: Add support of BQ25892 and BQ25896 chips - misc fixes" * tag 'for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply: (44 commits) power: supply: ipaq_micro_battery: remove unneeded semicolon power: supply: bq25890_charger: fix incorrect error return when bq25890_field_read fails power: supply: axp20x_usb_power: Only poll while offline power: supply: axp20x_usb_power: Add wakeup control power: supply: axp20x_usb_power: Allow offlining power: supply: axp20x_usb_power: Use a match structure power: suppy: ucs1002: Make the symbol 'ucs1002_regulator_enable' static power: reset: at91-poweroff: use proper master clock register offset power: reset: at91-poweroff: introduce struct shdwc_reg_config power: supply: bq25890_charger: Add DT and I2C ids for all supported chips dt-bindings: Add new chips to bq25890 binding documentation power: supply: bq25890_charger: Add support of BQ25892 and BQ25896 chips power: supply: core: Update sysfs-class-power ABI document power: supply: sbs-battery: Fix a signedness bug in sbs_get_battery_capacity() power: supply: ltc2941-battery-gauge: fix use-after-free power: supply: max17040: Correct IRQ wake handling power: supply: axp20x_usb_power: Remove unused device_node power: supply: axp20x_ac_power: Add wakeup control power: supply: axp20x_ac_power: Allow offlining power: supply: axp20x_ac_power: Fix reporting online status ...
-
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds authored
Pull devicetree updates from Rob Herring: - Update dtc to upstream v1.5.1-22-gc40aeb60b47a (plus 1 revert) - Fix for DMA coherent devices on Power - Rework and simplify the DT phandle cache code - DT schema conversions for LEDS, gpio-leds, STM32 dfsdm, STM32 UART, STM32 ROMEM, STM32 watchdog, STM32 DMAs, STM32 mlahb, STM32 RTC, STM32 RCC, STM32 syscon, rs485, Renesas rCar CSI2, Faraday FTIDE010, DWC2, Arm idle-states, Allwinner legacy resets, PRCM and clocks, Allwinner H6 OPP, Allwinner AHCI, Allwinner MBUS, Allwinner A31 CSI, Allwinner h/w codec, Allwinner A10 system ctrl, Allwinner SRAM, Allwinner USB PHY, Renesas CEU, generic PCI host, Arm Versatile PCI - New binding schemas for SATA and PATA controllers, TI and Infineon VR controllers, MAX31730 - New compatible strings for i.MX8QM, WCN3991, renesas,r8a77961-wdt, renesas,etheravb-r8a77961 - Add USB 'super-speed-plus' as a documented speed - Vendor prefixes for broadmobi, calaosystems, kam, and mps - Clean-up the multiple flavors of ST-Ericsson vendor prefixes * tag 'devicetree-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (66 commits) scripts/dtc: Revert "yamltree: Ensure consistent bracketing of properties with phandles" of: Add OF_DMA_DEFAULT_COHERENT & select it on powerpc dt-bindings: leds: Convert gpio-leds to DT schema dt-bindings: leds: Convert common LED binding to schema dt-bindings: PCI: Convert generic host binding to DT schema dt-bindings: PCI: Convert Arm Versatile binding to DT schema dt-bindings: Be explicit about installing deps dt-bindings: stm32: convert dfsdm to json-schema dt-bindings: serial: Convert STM32 UART to json-schema dt-bindings: serial: Convert rs485 bindings to json-schema dt-bindings: timer: Use non-empty ranges in example dt-bindings: arm-boards: typo fix dt-bindings: Add TI and Infineon VR Controllers as trivial devices dt-binding: usb: add "super-speed-plus" dt-bindings: rcar-csi2: Convert bindings to json-schema dt-bindings: iio: adc: ad7606: Fix wrong maxItems value dt-bindings: Convert Faraday FTIDE010 to DT schema dt-bindings: Create DT bindings for PATA controllers dt-bindings: Create DT bindings for SATA controllers dt: bindings: add vendor prefix for Kamstrup A/S ...
-
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) Various mptcp fixupes from Florian Westphal and Geery Uytterhoeven. 2) Don't clear the node/port GUIDs after we've assigned the correct values to them. From Leon Romanovsky. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: net/core: Do not clear VF index for node/port GUIDs query mptcp: Fix undefined mptcp_handle_ipv6_mapped for modular IPV6 net: drop_monitor: Use kstrdup udp: document udp_rcv_segment special case for looped packets mptcp: MPTCP_HMAC_TEST should depend on MPTCP mptcp: Fix incorrect IPV6 dependency check Revert "MAINTAINERS: mptcp@ mailing list is moderated" mptcp: handle tcp fallback when using syn cookies mptcp: avoid a lockdep splat when mcast group was joined mptcp: fix panic on user pointer access mptcp: defer freeing of cached ext until last moment net: mvneta: fix XDP support if sw bm is used as fallback sch_choke: Use kvcalloc mptcp: Fix build with PROC_FS disabled. MAINTAINERS: mptcp@ mailing list is moderated
-
git://git.kernel.org/pub/scm/linux/kernel/git/davem/ideLinus Torvalds authored
Pull IDE updates from David Miller: 1) Fix mem region name in tx4949ide driver, from Christophe JAILLET. 2) Make drive->dn read only, it should not be changeable by users. From Dan Carpenter. 3) Several cast fixups from Krzysztof Kozlowski. There is also going to be a removal of a now unused IDE driver, but that will come via the MIPS tree. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide: ide: make drive->dn read only ide: serverworks: potential overflow in svwks_set_pio_mode() cmd64x: potential buffer overflow in cmd64x_program_timings() ide: remove unneeded header include path to drivers/ide ide: qd65xx: Fix cast to pointer from integer of different size ide: ht6560b: Fix cast to pointer from integer of different size ide: remove set but not used variable 'hwif' ide: remove unnecessary touch_softlockup_watchdog ide: tx4939ide: Fix the name used in a 'devm_request_mem_region()' call ide: Use dev_get_drvdata where possible
-
git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparcLinus Torvalds authored
Pull sparc updates from David Miller: 1) Add a proper .exit.data section. 2) Fix ipc64_perm type definition, from Arnd Bergmann. 3) Support folded p4d page tables on sparc64, from Mike Rapport. 4) Remove uses of struct timex, also from Arnd Bergmann. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: y2038: sparc: remove use of struct timex sparc64: add support for folded p4d page tables sparc/console: kill off obsolete declarations sparc32: fix struct ipc64_perm type definition sparc32, leon: Stop adding vendor and device id to prom ambapp path components sparc: Add .exit.data section. sparc: remove unneeded uapi/asm/statfs.h
-
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds authored
Pull arm64 KVM fix from Catalin Marinas: "Set the correct MDCR_EL2 register value on the first run of a vCPU" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: KVM: arm64: Write arch.mdcr_el2 changes since last vcpu_load on VHE
-
Leon Romanovsky authored
VF numbers were assigned to node_guid and port_guid, but cleared right before such query calls were issued. It caused to return node/port GUIDs of VF index 0 for all VFs. Fixes: 30aad417 ("net/core: Add support for getting VF GUIDs") Reported-by:
Adrian Chiris <adrianc@mellanox.com> Signed-off-by:
Leon Romanovsky <leonro@mellanox.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Arnd Bergmann authored
'struct timex' is one of the last users of 'struct timeval' and is only referenced in one place in the kernel any more, to convert the user space timex into the kernel-internal version on sparc64, with a different tv_usec member type. As a preparation for hiding the time_t definition and everything using that in the kernel, change the implementation once more to only convert the timeval member, and then enclose the struct definition in an #ifdef. Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Reviewed-by:
Julian Calaby <julian.calaby@gmail.com> Acked-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Mike Rapoport authored
Implement primitives necessary for the 4th level folding, add walks of p4d level where appropriate and replace 5level-fixup.h with pgtable-nop4d.h. Signed-off-by:
Mike Rapoport <rppt@linux.ibm.com> Acked-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Dan Carpenter authored
The IDE core always sets ->dn correctly so changing it is never required. Setting it to a different value than assigned by IDE core is very likely to result in data corruption (due to wrong transfer timings being set on the controller etc.) Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Acked-by:
Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Tested-by:
Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Geert Uytterhoeven authored
If CONFIG_MPTCP=y, CONFIG_MPTCP_IPV6=n, and CONFIG_IPV6=m: ERROR: "mptcp_handle_ipv6_mapped" [net/ipv6/ipv6.ko] undefined! This does not happen if CONFIG_MPTCP_IPV6=y, as CONFIG_MPTCP_IPV6 selects CONFIG_IPV6, and thus forces CONFIG_IPV6 builtin. As exporting a symbol for an empty function would be a bit wasteful, fix this by providing a dummy version of mptcp_handle_ipv6_mapped() for the CONFIG_MPTCP_IPV6=n case. Rename mptcp_handle_ipv6_mapped() to mptcpv6_handle_mapped(), to make it clear this is a pure-IPV6 function, just like mptcpv6_init(). Fixes: cec37a6e ("mptcp: Handle MP_CAPABLE options for outgoing connections") Signed-off-by:
Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Joe Perches authored
Convert the equivalent but rather odd uses of kmemdup with __GFP_ZERO to the more common kstrdup and avoid unnecessary zeroing of copied over memory. Signed-off-by:
Joe Perches <joe@perches.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Willem de Bruijn authored
Commit 6cd021a5 ("udp: segment looped gso packets correctly") fixes an issue with rare udp gso multicast packets looped onto the receive path. The stable backport makes the narrowest change to target only these packets, when needed. As opposed to, say, expanding __udp_gso_segment, which is harder to reason to be free from unintended side-effects. But the resulting code is hardly self-describing. Document its purpose and rationale. Signed-off-by:
Willem de Bruijn <willemb@google.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Geert Uytterhoeven authored
As the MPTCP HMAC test is integrated into the MPTCP code, it can be built only when MPTCP is enabled. Hence when MPTCP is disabled, asking the user if the test code should be enabled is futile. Wrap the whole block of MPTCP-specific config options inside a check for MPTCP. While at it, drop the "default n" for MPTCP_HMAC_TEST, as that is the default anyway. Fixes: 65492c5a ("mptcp: move from sha1 (v0) to sha256 (v1)") Signed-off-by:
Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by:
Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
Geert Uytterhoeven authored
If CONFIG_MPTCP=y, CONFIG_MPTCP_IPV6=n, and CONFIG_IPV6=m: net/mptcp/protocol.o: In function `__mptcp_tcp_fallback': protocol.c:(.text+0x786): undefined reference to `inet6_stream_ops' Fix this by checking for CONFIG_MPTCP_IPV6 instead of CONFIG_IPV6, like is done in all other places in the mptcp code. Fixes: 8ab183de ("mptcp: cope with later TCP fallback") Signed-off-by:
Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by:
Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
git://github.com/skeggsb/linuxDave Airlie authored
A couple of OOPS fixes, fixes for TU1xx if firmware isn't available, better behaviour in the face of GPU faults, and a patch to make HD audio work again after runpm changes. Signed-off-by:
Dave Airlie <airlied@redhat.com> From: Ben Skeggs <skeggsb@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/ <CACAvsv4xcLF6Ahh7UYEesn-wBEksd2da+ghusBAdODMrH7Sz2A@mail.gmail.com
-
git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds authored
Pull mmu_notifier updates from Jason Gunthorpe: "This small series revises the names in mmu_notifier to make the code clearer and more readable" * tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: mm/mmu_notifiers: Use 'interval_sub' as the variable for mmu_interval_notifier mm/mmu_notifiers: Use 'subscription' as the variable name for mmu_notifier mm/mmu_notifier: Rename struct mmu_notifier_mm to mmu_notifier_subscriptions
-
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linuxLinus Torvalds authored
Pull thread management updates from Christian Brauner: "Sargun Dhillon over the last cycle has worked on the pidfd_getfd() syscall. This syscall allows for the retrieval of file descriptors of a process based on its pidfd. A task needs to have ptrace_may_access() permissions with PTRACE_MODE_ATTACH_REALCREDS (suggested by Oleg and Andy) on the target. One of the main use-cases is in combination with seccomp's user notification feature. As a reminder, seccomp's user notification feature was made available in v5.0. It allows a task to retrieve a file descriptor for its seccomp filter. The file descriptor is usually handed of to a more privileged supervising process. The supervisor can then listen for syscall events caught by the seccomp filter of the supervisee and perform actions in lieu of the supervisee, usually emulating syscalls. pidfd_getfd() is needed to expand its uses. There are currently two major users that wait on pidfd_getfd() and one future user: - Netflix, Sargun said, is working on a service mesh where users should be able to connect to a dns-based VIP. When a user connects to e.g. 1.2.3.4:80 that runs e.g. service "foo" they will be redirected to an envoy process. This service mesh uses seccomp user notifications and pidfd to intercept all connect calls and instead of connecting them to 1.2.3.4:80 connects them to e.g. 127.0.0.1:8080. - LXD uses the seccomp notifier heavily to intercept and emulate mknod() and mount() syscalls for unprivileged containers/processes. With pidfd_getfd() more uses-cases e.g. bridging socket connections will be possible. - The patchset has also seen some interest from the browser corner. Right now, Firefox is using a SECCOMP_RET_TRAP sandbox managed by a broker process. In the future glibc will start blocking all signals during dlopen() rendering this type of sandbox impossible. Hence, in the future Firefox will switch to a seccomp-user-nofication based sandbox which also makes use of file descriptor retrieval. The thread for this can be found at https://sourceware.org/ml/libc-alpha/2019-12/msg00079.html With pidfd_getfd() it is e.g. possible to bridge socket connections for the supervisee (binding to a privileged port) and taking actions on file descriptors on behalf of the supervisee in general. Sargun's first version was using an ioctl on pidfds but various people pushed for it to be a proper syscall which he duely implemented as well over various review cycles. Selftests are of course included. I've also added instructions how to deal with merge conflicts below. There's also a small fix coming from the kernel mentee project to correctly annotate struct sighand_struct with __rcu to fix various sparse warnings. We've received a few more such fixes and even though they are mostly trivial I've decided to postpone them until after -rc1 since they came in rather late and I don't want to risk introducing build warnings. Finally, there's a new prctl() command PR_{G,S}ET_IO_FLUSHER which is needed to avoid allocation recursions triggerable by storage drivers that have userspace parts that run in the IO path (e.g. dm-multipath, iscsi, etc). These allocation recursions deadlock the device. The new prctl() allows such privileged userspace components to avoid allocation recursions by setting the PF_MEMALLOC_NOIO and PF_LESS_THROTTLE flags. The patch carries the necessary acks from the relevant maintainers and is routed here as part of prctl() thread-management." * tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: prctl: PR_{G,S}ET_IO_FLUSHER to support controlling memory reclaim sched.h: Annotate sighand_struct with __rcu test: Add test for pidfd getfd arch: wire up pidfd_getfd syscall pid: Implement pidfd_getfd syscall vfs, fdtable: Add fget_task helper
-
git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull io_uring updates from Jens Axboe: - Support for various new opcodes (fallocate, openat, close, statx, fadvise, madvise, openat2, non-vectored read/write, send/recv, and epoll_ctl) - Faster ring quiesce for fileset updates - Optimizations for overflow condition checking - Support for max-sized clamping - Support for probing what opcodes are supported - Support for io-wq backend sharing between "sibling" rings - Support for registering personalities - Lots of little fixes and improvements * tag 'for-5.6/io_uring-vfs-2020-01-29' of git://git.kernel.dk/linux-block: (64 commits) io_uring: add support for epoll_ctl(2) eventpoll: support non-blocking do_epoll_ctl() calls eventpoll: abstract out epoll_ctl() handler io_uring: fix linked command file table usage io_uring: support using a registered personality for commands io_uring: allow registering credentials io_uring: add io-wq workqueue sharing io-wq: allow grabbing existing io-wq io_uring/io-wq: don't use static creds/mm assignments io-wq: make the io_wq ref counted io_uring: fix refcounting with batched allocations at OOM io_uring: add comment for drain_next io_uring: don't attempt to copy iovec for READ/WRITE io_uring: honor IOSQE_ASYNC for linked reqs io_uring: prep req when do IOSQE_ASYNC io_uring: use labeled array init in io_op_defs io_uring: optimise sqe-to-req flags translation io_uring: remove REQ_F_IO_DRAINED io_uring: file switch work needs to get flushed on exit io_uring: hide uring_fd in ctx ...
-
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds authored
Pull SCSI updates from James Bottomley: "This series is slightly unusual because it includes Arnd's compat ioctl tree here: 1c46a2cf Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue Excluding Arnd's changes, this is mostly an update of the usual drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas. There are a couple of core and base updates around error propagation and atomicity in the attribute container base we use for the SCSI transport classes. The rest is minor changes and updates" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (149 commits) scsi: hisi_sas: Rename hisi_sas_cq.pci_irq_mask scsi: hisi_sas: Add prints for v3 hw interrupt converge and automatic affinity scsi: hisi_sas: Modify the file permissions of trigger_dump to write only scsi: hisi_sas: Replace magic number when handle channel interrupt scsi: hisi_sas: replace spin_lock_irqsave/spin_unlock_restore with spin_lock/spin_unlock scsi: hisi_sas: use threaded irq to process CQ interrupts scsi: ufs: Use UFS device indicated maximum LU number scsi: ufs: Add max_lu_supported in struct ufs_dev_info scsi: ufs: Delete is_init_prefetch from struct ufs_hba scsi: ufs: Inline two functions into their callers scsi: ufs: Move ufshcd_get_max_pwr_mode() to ufshcd_device_params_init() scsi: ufs: Split ufshcd_probe_hba() based on its called flow scsi: ufs: Delete struct ufs_dev_desc scsi: ufs: Fix ufshcd_probe_hba() reture value in case ufshcd_scsi_add_wlus() fails scsi: ufs-mediatek: enable low-power mode for hibern8 state scsi: ufs: export some functions for vendor usage scsi: ufs-mediatek: add dbg_register_dump implementation scsi: qla2xxx: Fix a NULL pointer dereference in an error path scsi: qla1280: Make checking for 64bit support consistent scsi: megaraid_sas: Update driver version to 07.713.01.00-rc1 ...
-
Linus Torvalds authored
Merge tag 'for-5.6/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Fix DM core's potential for q->make_request_fn NULL pointer in the unlikely case that a DM device is created without a DM table and then accessed due to upper-layer userspace code or user error. - Fix DM thin-provisioning's metadata_pre_commit_callback to not use memory after it is free'd. Also refactor code to disallow changing the thin-pool's data device once in use -- doing so guarantees smae lifetime of pool's data device relative to the pool metadata. - Fix DM space maps used by DM thinp and DM cache to avoid reuse of a already used block. This race was identified with extremely heavy snapshot use in the context of DM thin provisioning. - Fix DM raid's table status relative to an active rebuild. - Fix DM crypt to use GFP_NOIO rather than GFP_NOFS in call to skcipher_request_alloc(). Also fix benbi IV constructor crash if used in authenticated mode. - Add DM crypt support for Elephant diffuser to allow for Bitlocker compatibility. - Fix DM verity target to not prefetch hash blocks for data that has already been verified. - Fix DM writecache's incorrect flush sequence during commit when in SSD mode. - Improve DM writecache's sequential write performance on SSDs. - Add DM zoned target support for zone sizes smaller than 128MiB. - Add DM multipath 'queue_if_no_path_timeout_secs' module param to allow timeout if path isn't reinstated. This allows users a kernel safety-net against IO hanging indefinitely, due to no active paths, that has historically only been provided by multipathd userspace. - Various DM code cleanups to use true/false rather than 1/0, a variable rename in dm-dust, and fix for a math error in comment for DM thin metadata's ondisk format. * tag 'for-5.6/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (21 commits) dm: fix potential for q->make_request_fn NULL pointer dm writecache: improve performance of large linear writes on SSDs dm mpath: Add timeout mechanism for queue_if_no_path dm thin: change data device's flush_bio to be member of struct pool dm thin: don't allow changing data device during thin-pool reload dm thin: fix use-after-free in metadata_pre_commit_callback dm thin metadata: use pool locking at end of dm_pool_metadata_close dm writecache: fix incorrect flush sequence when doing SSD mode commit dm crypt: fix benbi IV constructor crash if used in authenticated mode dm crypt: Implement Elephant diffuser for Bitlocker compatibility dm space map common: fix to ensure new block isn't already in use dm verity: don't prefetch hash blocks for already-verified data dm crypt: fix GFP flags passed to skcipher_request_alloc() dm thin metadata: Fix trivial math error in on-disk format documentation dm thin metadata: use true/false for bool variable dm snapshot: use true/false for bool variable dm bio prison v2: use true/false for bool variable dm mpath: use true/false for bool variable dm zoned: support zone sizes smaller than 128MiB dm raid: table line rebuild status fixes ...
-
git://git.lwn.net/linuxLinus Torvalds authored
Pull documentation updates from Jonathan Corbet: "It has been a relatively quiet cycle for documentation, but there's still a couple of things of note: - Conversion of the NFS documentation to RST - A new document on how to help with documentation (and a maintainer profile entry too) Plus the usual collection of typo fixes, etc" * tag 'docs-5.6' of git://git.lwn.net/linux: (40 commits) docs: filesystems: add overlayfs to index.rst docs: usb: remove some broken references scripts/find-unused-docs: Fix massive false positives docs: nvdimm: use ReST notation for subsection zram: correct documentation about sysfs node of huge page writeback Documentation: zram: various fixes in zram.rst Add a maintainer entry profile for documentation Add a document on how to contribute to the documentation docs: Keep up with the location of NoUri Documentation: Call out example SYM_FUNC_* usage as x86-specific Documentation: nfs: fault_injection: convert to ReST Documentation: nfs: pnfs-scsi-server: convert to ReST Documentation: nfs: convert pnfs-block-server to ReST Documentation: nfs: idmapper: convert to ReST Documentation: convert nfsd-admin-interfaces to ReST Documentation: nfs-rdma: convert to ReST Documentation: nfsroot.rst: COSMETIC: refill a paragraph Documentation: nfsroot.txt: convert to ReST Documentation: convert nfs.txt to ReST Documentation: filesystems: convert vfat.txt to RST ...
-
Linus Torvalds authored
Merge tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest kunit updates from Shuah Khan: "This kunit update consists of: - Support for building kunit as a module from Alan Maguire - AppArmor KUnit tests for policy unpack from Mike Salvatore" * tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: kunit: building kunit as a module breaks allmodconfig kunit: update documentation to describe module-based build kunit: allow kunit to be loaded as a module kunit: remove timeout dependence on sysctl_hung_task_timeout_seconds kunit: allow kunit tests to be loaded as a module kunit: hide unexported try-catch interface in try-catch-impl.h kunit: move string-stream.h to lib/kunit apparmor: add AppArmor KUnit tests for policy unpack
-
Linus Torvalds authored
Merge tag 'linux-kselftest-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest update from Shuah Khan: "This Kselftest update consists of several fixes to framework and individual tests. In addition, it enables LKDTM tests adding lkdtm target to kselftest Makefile" * tag 'linux-kselftest-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: selftests/ftrace: fix glob selftest selftests: settings: tests can be in subsubdirs kselftest: Minimise dependency of get_size on C library interfaces selftests/livepatch: Remove unused local variable in set_ftrace_enabled() selftests/livepatch: Replace set_dynamic_debug() with setup_config() in README selftests/lkdtm: Add tests for LKDTM targets selftests: Uninitialized variable in test_cgcore_proc_migration() selftests: fix build behaviour on targets' failures
-
Linus Torvalds authored
Merge tag 'y2038-drivers-for-v5.6-signed' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground Pull y2038 updates from Arnd Bergmann: "Core, driver and file system changes These are updates to device drivers and file systems that for some reason or another were not included in the kernel in the previous y2038 series. I've gone through all users of time_t again to make sure the kernel is in a long-term maintainable state, replacing all remaining references to time_t with safe alternatives. Some related parts of the series were picked up into the nfsd, xfs, alsa and v4l2 trees. A final set of patches in linux-mm removes the now unused time_t/timeval/timespec types and helper functions after all five branches are merged for linux-5.6, ensuring that no new users get merged. As a result, linux-5.6, or my backport of the patches to 5.4 [1], should be the first release that can serve as a base for a 32-bit system designed to run beyond year 2038, with a few remaining caveats: - All user space must be compiled with a 64-bit time_t, which will be supported in the coming musl-1.2 and glibc-2.32 releases, along with installed kernel headers from linux-5.6 or higher. - Applications that use the system call interfaces directly need to be ported to use the time64 syscalls added in linux-5.1 in place of the existing system calls. This impacts most users of futex() and seccomp() as well as programming languages that have their own runtime environment not based on libc. - Applications that use a private copy of kernel uapi header files or their contents may need to update to the linux-5.6 version, in particular for sound/asound.h, xfs/xfs_fs.h, linux/input.h, linux/elfcore.h, linux/sockios.h, linux/timex.h and linux/can/bcm.h. - A few remaining interfaces cannot be changed to pass a 64-bit time_t in a compatible way, so they must be configured to use CLOCK_MONOTONIC times or (with a y2106 problem) unsigned 32-bit timestamps. Most importantly this impacts all users of 'struct input_event'. - All y2038 problems that are present on 64-bit machines also apply to 32-bit machines. In particular this affects file systems with on-disk timestamps using signed 32-bit seconds: ext4 with ext3-style small inodes, ext2, xfs (to be fixed soon) and ufs" [1] https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/log/?h=y2038-endgame * tag 'y2038-drivers-for-v5.6-signed' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (21 commits) Revert "drm/etnaviv: reject timeouts with tv_nsec >= NSEC_PER_SEC" y2038: sh: remove timeval/timespec usage from headers y2038: sparc: remove use of struct timex y2038: rename itimerval to __kernel_old_itimerval y2038: remove obsolete jiffies conversion functions nfs: fscache: use timespec64 in inode auxdata nfs: fix timstamp debug prints nfs: use time64_t internally sunrpc: convert to time64_t for expiry drm/etnaviv: avoid deprecated timespec drm/etnaviv: reject timeouts with tv_nsec >= NSEC_PER_SEC drm/msm: avoid using 'timespec' hfs/hfsplus: use 64-bit inode timestamps hostfs: pass 64-bit timestamps to/from user space packet: clarify timestamp overflow tsacct: add 64-bit btime field acct: stop using get_seconds() um: ubd: use 64-bit time_t where possible xtensa: ISS: avoid struct timeval dlm: use SO_SNDTIMEO_NEW instead of SO_SNDTIMEO_OLD ...
-
git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printkLinus Torvalds authored
Pull printk update from Petr Mladek: "Prevent replaying log on all consoles" * tag 'printk-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: printk: fix exclusive_console replaying
-
Jens Axboe authored
This adds IORING_OP_EPOLL_CTL, which can perform the same work as the epoll_ctl(2) system call. Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
Also make it available outside of epoll, along with the helper that decides if we need to copy the passed in epoll_event. Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
No functional changes in this patch. Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Jens Axboe authored
We're not consistent in how the file table is grabbed and assigned if we have a command linked that requires the use of it. Add ->file_table to the io_op_defs[] array, and use that to determine when to grab the table instead of having the handlers set it if they need to defer. This also means we can kill the IO_WQ_WORK_NEEDS_FILES flag. We always initialize work->files, so io-wq can just check for that. Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofsLinus Torvalds authored
Pull erofs updates from Gao Xiang: "A regression fix, several cleanups and (maybe) plus an upcoming new mount api convert patch as a part of vfs update are considered available for this cycle. All commits have been in linux-next and tested with no smoke out. Summary: - fix an out-of-bound read access introduced in v5.3, which could rarely cause data corruption - various cleanup patches" * tag 'erofs-for-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: clean up z_erofs_submit_queue() erofs: fold in postsubmit_is_all_bypassed() erofs: fix out-of-bound read for shifted uncompressed block erofs: remove void tagging/untagging of workgroup pointers erofs: remove unused tag argument while registering a workgroup erofs: remove unused tag argument while finding a workgroup erofs: correct indentation of an assigned structure inside a function
-
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds authored
Pull adfs updates from Al Viro: "adfs stuff for this cycle" * 'work.adfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (42 commits) fs/adfs: bigdir: Fix an error code in adfs_fplus_read() Documentation: update adfs filesystem documentation fs/adfs: mostly divorse inode number from indirect disc address fs/adfs: super: add support for E and E+ floppy image formats fs/adfs: super: extract filesystem block probe fs/adfs: dir: remove debug in adfs_dir_update() fs/adfs: super: fix inode dropping fs/adfs: bigdir: implement directory update support fs/adfs: bigdir: calculate and validate directory checkbyte fs/adfs: bigdir: directory validation strengthening fs/adfs: bigdir: extract directory validation fs/adfs: bigdir: factor out directory entry offset calculation fs/adfs: newdir: split out directory commit from update fs/adfs: newdir: clean up adfs_f_update() fs/adfs: newdir: merge adfs_dir_read() into adfs_f_read() fs/adfs: newdir: improve directory validation fs/adfs: newdir: factor out directory format validation fs/adfs: dir: use pointers to access directory head/tails fs/adfs: dir: add more efficient iterate() per-format method fs/adfs: dir: switch to iterate_shared method ...
-
Mat Martineau authored
This reverts commit 74759e16 . mptcp@lists.01.org accepts messages from non-subscribers. There was an invisible and unexpected server-wide rule limiting the number of recipients for subscribers and non-subscribers alike, and that has now been turned off for this list. Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by:
Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
-
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds authored
Pull openat2 support from Al Viro: "This is the openat2() series from Aleksa Sarai. I'm afraid that the rest of namei stuff will have to wait - it got zero review the last time I'd posted #work.namei, and there had been a leak in the posted series I'd caught only last weekend. I was going to repost it on Monday, but the window opened and the odds of getting any review during that... Oh, well. Anyway, openat2 part should be ready; that _did_ get sane amount of review and public testing, so here it comes" From Aleksa's description of the series: "For a very long time, extending openat(2) with new features has been incredibly frustrating. This stems from the fact that openat(2) is possibly the most famous counter-example to the mantra "don't silently accept garbage from userspace" -- it doesn't check whether unknown flags are present[1]. This means that (generally) the addition of new flags to openat(2) has been fraught with backwards-compatibility issues (O_TMPFILE has to be defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old kernels gave errors, since it's insecure to silently ignore the flag[2]). All new security-related flags therefore have a tough road to being added to openat(2). Furthermore, the need for some sort of control over VFS's path resolution (to avoid malicious paths resulting in inadvertent breakouts) has been a very long-standing desire of many userspace applications. This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset (which was a variant of David Drysdale's O_BENEATH patchset[4] which was a spin-off of the Capsicum project[5]) with a few additions and changes made based on the previous discussion within [6] as well as others I felt were useful. In line with the conclusions of the original discussion of AT_NO_JUMPS, the flag has been split up into separate flags. However, instead of being an openat(2) flag it is provided through a new syscall openat2(2) which provides several other improvements to the openat(2) interface (see the patch description for more details). The following new LOOKUP_* flags are added: LOOKUP_NO_XDEV: Blocks all mountpoint crossings (upwards, downwards, or through absolute links). Absolute pathnames alone in openat(2) do not trigger this. Magic-link traversal which implies a vfsmount jump is also blocked (though magic-link jumps on the same vfsmount are permitted). LOOKUP_NO_MAGICLINKS: Blocks resolution through /proc/$pid/fd-style links. This is done by blocking the usage of nd_jump_link() during resolution in a filesystem. The term "magic-links" is used to match with the only reference to these links in Documentation/, but I'm happy to change the name. It should be noted that this is different to the scope of ~LOOKUP_FOLLOW in that it applies to all path components. However, you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it will *not* fail (assuming that no parent component was a magic-link), and you will have an fd for the magic-link. In order to correctly detect magic-links, the introduction of a new LOOKUP_MAGICLINK_JUMPED state flag was required. LOOKUP_BENEATH: Disallows escapes to outside the starting dirfd's tree, using techniques such as ".." or absolute links. Absolute paths in openat(2) are also disallowed. Conceptually this flag is to ensure you "stay below" a certain point in the filesystem tree -- but this requires some additional to protect against various races that would allow escape using "..". Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it can trivially beam you around the filesystem (breaking the protection). In future, there might be similar safety checks done as in LOOKUP_IN_ROOT, but that requires more discussion. In addition, two new flags are added that expand on the above ideas: LOOKUP_NO_SYMLINKS: Does what it says on the tin. No symlink resolution is allowed at all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this can still be used with NOFOLLOW to open an fd for the symlink as long as no parent path had a symlink component. LOOKUP_IN_ROOT: This is an extension of LOOKUP_BENEATH that, rather than blocking attempts to move past the root, forces all such movements to be scoped to the starting point. This provides chroot(2)-like protection but without the cost of a chroot(2) for each filesystem operation, as well as being safe against race attacks that chroot(2) is not. If a race is detected (as with LOOKUP_BENEATH) then an error is generated, and similar to LOOKUP_BENEATH it is not permitted to cross magic-links with LOOKUP_IN_ROOT. The primary need for this is from container runtimes, which currently need to do symlink scoping in userspace[7] when opening paths in a potentially malicious container. There is a long list of CVEs that could have bene mitigated by having RESOLVE_THIS_ROOT (such as CVE-2017-1002101, CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a few). In order to make all of the above more usable, I'm working on libpathrs[8] which is a C-friendly library for safe path resolution. It features a userspace-emulated backend if the kernel doesn't support openat2(2). Hopefully we can get userspace to switch to using it, and thus get openat2(2) support for free once it's ready. Future work would include implementing things like RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow programs to be sure they don't hit DoSes though stale NFS handles)" * 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Documentation: path-lookup: include new LOOKUP flags selftests: add openat2(2) selftests open: introduce openat2(2) syscall namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution namei: LOOKUP_IN_ROOT: chroot-like scoped resolution namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution namei: LOOKUP_NO_XDEV: block mountpoint crossing namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution namei: LOOKUP_NO_SYMLINKS: block symlink resolution namei: allow set_root() to produce errors namei: allow nd_jump_link() to produce errors nsfs: clean-up ns_get_path() signature to return int namei: only return -ECHILD from follow_dotdot_rcu()
-