user/sven/linux.git/include, branch v6.6.18

eventfs: Hold eventfs_mutex when calling callback functions

2024-02-23T08:25:21Z

commit 44365329f8219fc379097c2c9a75ff53f123764f upstream. The callback function that is used to create inodes and dentries is not protected by anything and the data that is passed to it could become stale. After eventfs_remove_dir() is called by the tracing system, it is free to remove the events that are associated to that directory. Unfortunately, that means the callbacks must not be called after that. CPU0 CPU1 ---- ---- eventfs_root_lookup() { eventfs_remove_dir() { mutex_lock(&event_mutex); ei->is_freed = set; mutex_unlock(&event_mutex); } kfree(event_call); for (...) { entry = &ei->entries[i]; r = entry->callback() { call = data; // call == event_call above if (call->flags ...) [ USE AFTER FREE BUG ] The safest way to protect this is to wrap the callback with: mutex_lock(&eventfs_mutex); if (!ei->is_freed) r = entry->callback(); else r = -1; mutex_unlock(&eventfs_mutex); This will make sure that the callback will not be called after it is freed. But now it needs to be known that the callback is called while holding internal eventfs locks, and that it must not call back into the eventfs / tracefs system. There's no reason it should anyway, but document that as well. Link: https://lore.kernel.org/all/CA+G9fYu9GOEbD=rR5eMR-=HJ8H6rMsbzDC2ZY5=Y50WpWAE7_Q@mail.gmail.com/ Link: https://lkml.kernel.org/r/20231101172649.906696613@goodmis.org Cc: Ajay Kaher Cc: Mark Rutland Cc: Andrew Morton Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode") Reported-by: Linux Kernel Functional Testing Reported-by: Naresh Kamboju Tested-by: Linux Kernel Functional Testing Tested-by: Naresh Kamboju Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

eventfs: Use eventfs_remove_events_dir()

2024-02-23T08:25:19Z

commit 2819f23ac12ce93ff79ca7a54597df9a4a1f6331 upstream. The update to removing the eventfs_file changed the way the events top level directory was handled. Instead of returning a dentry, it now returns the eventfs_inode. In this changed, the removing of the events top level directory is not much different than removing any of the other directories. Because of this, the removal just called eventfs_remove_dir() instead of eventfs_remove_events_dir(). Although eventfs_remove_dir() does the clean up, it misses out on the dget() of the ei->dentry done in eventfs_create_events_dir(). It makes more sense to match eventfs_create_events_dir() with a specific function eventfs_remove_events_dir() and this specific function can then perform the dput() to the dentry that had the dget() when it was created. Fixes: 5790b1fb3d67 ("eventfs: Remove eventfs_file and just use eventfs_inode") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202310051743.y9EobbUr-lkp@intel.com/ Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

eventfs: Remove eventfs_file and just use eventfs_inode

2024-02-23T08:25:19Z

commit 5790b1fb3d672d9a1fe3881a7181dfdbe741568f upstream. Instead of having a descriptor for every file represented in the eventfs directory, only have the directory itself represented. Change the API to send in a list of entries that represent all the files in the directory (but not other directories). The entry list contains a name and a callback function that will be used to create the files when they are accessed. struct eventfs_inode *eventfs_create_events_dir(const char *name, struct dentry *parent, const struct eventfs_entry *entries, int size, void *data); is used for the top level eventfs directory, and returns an eventfs_inode that will be used by: struct eventfs_inode *eventfs_create_dir(const char *name, struct eventfs_inode *parent, const struct eventfs_entry *entries, int size, void *data); where both of the above take an array of struct eventfs_entry entries for every file that is in the directory. The entries are defined by: typedef int (*eventfs_callback)(const char *name, umode_t *mode, void **data, const struct file_operations **fops); struct eventfs_entry { const char *name; eventfs_callback callback; }; Where the name is the name of the file and the callback gets called when the file is being created. The callback passes in the name (in case the same callback is used for multiple files), a pointer to the mode, data and fops. The data will be pointing to the data that was passed in eventfs_create_dir() or eventfs_create_events_dir() but may be overridden to point to something else, as it will be used to point to the inode->i_private that is created. The information passed back from the callback is used to create the dentry/inode. If the callback fills the data and the file should be created, it must return a positive number. On zero or negative, the file is ignored. This logic may also be used as a prototype to convert entire pseudo file systems into just-in-time allocation. The "show_events_dentry" file has been updated to show the directories, and any files they have. With just the eventfs_file allocations: Before after deltas for meminfo (in kB): MemFree: -14360 MemAvailable: -14260 Buffers: 40 Cached: 24 Active: 44 Inactive: 48 Inactive(anon): 28 Active(file): 44 Inactive(file): 20 Dirty: -4 AnonPages: 28 Mapped: 4 KReclaimable: 132 Slab: 1604 SReclaimable: 132 SUnreclaim: 1472 Committed_AS: 12 Before after deltas for slabinfo: : [ * = ] ext4_inode_cache 27 [* 1184 = 31968 ] extent_status 102 [* 40 = 4080 ] tracefs_inode_cache 144 [* 656 = 94464 ] buffer_head 39 [* 104 = 4056 ] shmem_inode_cache 49 [* 800 = 39200 ] filp -53 [* 256 = -13568 ] dentry 251 [* 192 = 48192 ] lsm_file_cache 277 [* 32 = 8864 ] vm_area_struct -14 [* 184 = -2576 ] trace_event_file 1748 [* 88 = 153824 ] kmalloc-1k 35 [* 1024 = 35840 ] kmalloc-256 49 [* 256 = 12544 ] kmalloc-192 -28 [* 192 = -5376 ] kmalloc-128 -30 [* 128 = -3840 ] kmalloc-96 10581 [* 96 = 1015776 ] kmalloc-64 3056 [* 64 = 195584 ] kmalloc-32 1291 [* 32 = 41312 ] kmalloc-16 2310 [* 16 = 36960 ] kmalloc-8 9216 [* 8 = 73728 ] Free memory dropped by 14,360 kB Available memory dropped by 14,260 kB Total slab additions in size: 1,771,032 bytes With this change: Before after deltas for meminfo (in kB): MemFree: -12084 MemAvailable: -11976 Buffers: 32 Cached: 32 Active: 72 Inactive: 168 Inactive(anon): 176 Active(file): 72 Inactive(file): -8 Dirty: 24 AnonPages: 196 Mapped: 8 KReclaimable: 148 Slab: 836 SReclaimable: 148 SUnreclaim: 688 Committed_AS: 324 Before after deltas for slabinfo: : [ * = ] tracefs_inode_cache 144 [* 656 = 94464 ] shmem_inode_cache -23 [* 800 = -18400 ] filp -92 [* 256 = -23552 ] dentry 179 [* 192 = 34368 ] lsm_file_cache -3 [* 32 = -96 ] vm_area_struct -13 [* 184 = -2392 ] trace_event_file 1748 [* 88 = 153824 ] kmalloc-1k -49 [* 1024 = -50176 ] kmalloc-256 -27 [* 256 = -6912 ] kmalloc-128 1864 [* 128 = 238592 ] kmalloc-64 4685 [* 64 = 299840 ] kmalloc-32 -72 [* 32 = -2304 ] kmalloc-16 256 [* 16 = 4096 ] total = 721352 Free memory dropped by 12,084 kB Available memory dropped by 11,976 kB Total slab additions in size: 721,352 bytes That's over 2 MB in savings per instance for free and available memory, and over 1 MB in savings per instance of slab memory. Link: https://lore.kernel.org/linux-trace-kernel/20231003184059.4924468e@gandalf.local.home Link: https://lore.kernel.org/linux-trace-kernel/20231004165007.43d79161@gandalf.local.home Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Andrew Morton Cc: Ajay Kaher Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

netfilter: ipset: fix performance regression in swap operation

2024-02-23T08:25:18Z

commit 97f7cf1cd80eeed3b7c808b7c12463295c751001 upstream. The patch "netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test", commit 28628fa9 fixes a race condition. But the synchronize_rcu() added to the swap function unnecessarily slows it down: it can safely be moved to destroy and use call_rcu() instead. Eric Dumazet pointed out that simply calling the destroy functions as rcu callback does not work: sets with timeout use garbage collectors which need cancelling at destroy which can wait. Therefore the destroy functions are split into two: cancelling garbage collectors safely at executing the command received by netlink and moving the remaining part only into the rcu callback. Link: https://lore.kernel.org/lkml/C0829B10-EAA6-4809-874E-E1E9C05A8D84@automattic.com/ Fixes: 28628fa952fe ("netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test") Reported-by: Ale Crismani Reported-by: David Wang <00107082@163.com> Tested-by: David Wang <00107082@163.com> Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

blk-wbt: Fix detection of dirty-throttled tasks

2024-02-23T08:25:16Z

commit f814bdda774c183b0cc15ec8f3b6e7c6f4527ba5 upstream. The detection of dirty-throttled tasks in blk-wbt has been subtly broken since its beginning in 2016. Namely if we are doing cgroup writeback and the throttled task is not in the root cgroup, balance_dirty_pages() will set dirty_sleep for the non-root bdi_writeback structure. However blk-wbt checks dirty_sleep only in the root cgroup bdi_writeback structure. Thus detection of recently throttled tasks is not working in this case (we noticed this when we switched to cgroup v2 and suddently writeback was slow). Since blk-wbt has no easy way to get to proper bdi_writeback and furthermore its intention has always been to work on the whole device rather than on individual cgroups, just move the dirty_sleep timestamp from bdi_writeback to backing_dev_info. That fixes the checking for recently throttled task and saves memory for everybody as a bonus. CC: stable@vger.kernel.org Fixes: b57d74aff9ab ("writeback: track if we're sleeping on progress in balance_dirty_pages()") Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20240123175826.21452-1-jack@suse.cz [axboe: fixup indentation errors] Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

ASoC: tas2781: add module parameter to tascodec_init()

2024-02-23T08:25:14Z

commit 34a1066981a967eab619938e7b35a9be6b4c34e1 upstream. The tascodec_init() of the snd-soc-tas2781-comlib module is called from snd-soc-tas2781-i2c and snd-hda-scodec-tas2781-i2c modules. It calls request_firmware_nowait() with parameter THIS_MODULE and a cont/callback from the latter modules. The latter modules can be removed while their callbacks are running, resulting in a general protection failure. Add module parameter to tascodec_init() so request_firmware_nowait() can be called with the module of the callback. Fixes: ef3bcde75d06 ("ASoC: tas2781: Add tas2781 driver") CC: stable@vger.kernel.org Signed-off-by: Gergo Koteles Link: https://lore.kernel.org/r/118dad922cef50525e5aab09badef2fa0eb796e5.1707076603.git.soyer@irl.hu Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman

serial: core: introduce uart_port_tx_flags()

2024-02-23T08:25:10Z

commit 3ee07964d407411fd578a3bc998de44fd64d266a upstream. And an enum with a flag: UART_TX_NOSTOP. To NOT call __port->ops->stop_tx() when the circular buffer is empty. mxs-uart needs this (see the next patch). Signed-off-by: "Jiri Slaby (SUSE)" Cc: stable Tested-by: Emil Kronborg Link: https://lore.kernel.org/r/20240201105557.28043-1-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

iio: imu: adis: ensure proper DMA alignment

2024-02-23T08:25:06Z

commit 8e98b87f515d8c4bae521048a037b2cc431c3fd5 upstream. Aligning the buffer to the L1 cache is not sufficient in some platforms as they might have larger cacheline sizes for caches after L1 and thus, we can't guarantee DMA safety. That was the whole reason to introduce IIO_DMA_MINALIGN in [1]. Do the same for the sigma_delta ADCs. [1]: https://lore.kernel.org/linux-iio/20220508175712.647246-2-jic23@kernel.org/ Fixes: ccd2b52f4ac6 ("staging:iio: Add common ADIS library") Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240117-adis-improv-v1-1-7f90e9fad200@analog.com Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman

iio: adc: ad_sigma_delta: ensure proper DMA alignment

2024-02-23T08:25:06Z

commit 59598510be1d49e1cff7fd7593293bb8e1b2398b upstream. Aligning the buffer to the L1 cache is not sufficient in some platforms as they might have larger cacheline sizes for caches after L1 and thus, we can't guarantee DMA safety. That was the whole reason to introduce IIO_DMA_MINALIGN in [1]. Do the same for the sigma_delta ADCs. [1]: https://lore.kernel.org/linux-iio/20220508175712.647246-2-jic23@kernel.org/ Fixes: 0fb6ee8d0b5e ("iio: ad_sigma_delta: Don't put SPI transfer buffer on the stack") Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240117-dev_sigma_delta_no_irq_flags-v1-1-db39261592cf@analog.com Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman

iio: commom: st_sensors: ensure proper DMA alignment

2024-02-23T08:25:06Z

commit 862cf85fef85becc55a173387527adb4f076fab0 upstream. Aligning the buffer to the L1 cache is not sufficient in some platforms as they might have larger cacheline sizes for caches after L1 and thus, we can't guarantee DMA safety. That was the whole reason to introduce IIO_DMA_MINALIGN in [1]. Do the same for st_sensors common buffer. While at it, moved the odr_lock before buffer_data as we definitely don't want any other data to share a cacheline with the buffer. [1]: https://lore.kernel.org/linux-iio/20220508175712.647246-2-jic23@kernel.org/ Fixes: e031d5f558f1 ("iio:st_sensors: remove buffer allocation at each buffer enable") Signed-off-by: Nuno Sa Cc: Link: https://lore.kernel.org/r/20240131-dev_dma_safety_stm-v2-1-580c07fae51b@analog.com Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman