kernel/linux.git/include/linux, branch v6.1.70

mm/damon/core: make damon_start() waits until kdamond_fn() starts

2024-01-01T12:39:08+00:00

commit 6376a824595607e99d032a39ba3394988b4fce96 upstream. The cleanup tasks of kdamond threads including reset of corresponding DAMON context's ->kdamond field and decrease of global nr_running_ctxs counter is supposed to be executed by kdamond_fn(). However, commit 0f91d13366a4 ("mm/damon: simplify stop mechanism") made neither damon_start() nor damon_stop() ensure the corresponding kdamond has started the execution of kdamond_fn(). As a result, the cleanup can be skipped if damon_stop() is called fast enough after the previous damon_start(). Especially the skipped reset of ->kdamond could cause a use-after-free. Fix it by waiting for start of kdamond_fn() execution from damon_start(). Link: https://lkml.kernel.org/r/20231208175018.63880-1-sj@kernel.org Fixes: 0f91d13366a4 ("mm/damon: simplify stop mechanism") Signed-off-by: SeongJae Park Reported-by: Jakub Acs Cc: Changbin Du Cc: Jakub Acs Cc: # 5.15.x Signed-off-by: Andrew Morton Signed-off-by: SeongJae Park Signed-off-by: Greg Kroah-Hartman

dm thin metadata: Fix ABBA deadlock by resetting dm_bufio_client

2024-01-01T12:39:05+00:00

[ Upstream commit d48300120627a1cb98914738fff38b424625b8ad ] As described in commit 8111964f1b85 ("dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata"), ABBA deadlocks will be triggered because shrinker_rwsem currently needs to held by dm_pool_abort_metadata() as a side-effect of thin-pool metadata operation failure. The following three problem scenarios have been noticed: 1) Described by commit 8111964f1b85 ("dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata") 2) shrinker_rwsem and throttle->lock P1(drop cache) P2(kworker) drop_caches_sysctl_handler drop_slab shrink_slab down_read(&shrinker_rwsem) - LOCK A do_shrink_slab super_cache_scan prune_icache_sb dispose_list evict ext4_evict_inode ext4_clear_inode ext4_discard_preallocations ext4_mb_load_buddy_gfp ext4_mb_init_cache ext4_wait_block_bitmap __ext4_error ext4_handle_error ext4_commit_super ... dm_submit_bio do_worker throttle_work_update down_write(&t->lock) -- LOCK B process_deferred_bios commit metadata_operation_failed dm_pool_abort_metadata dm_block_manager_create dm_bufio_client_create register_shrinker down_write(&shrinker_rwsem) -- LOCK A thin_map thin_bio_map thin_defer_bio_with_throttle throttle_lock down_read(&t->lock) - LOCK B 3) shrinker_rwsem and wait_on_buffer P1(drop cache) P2(kworker) drop_caches_sysctl_handler drop_slab shrink_slab down_read(&shrinker_rwsem) - LOCK A do_shrink_slab ... ext4_wait_block_bitmap __ext4_error ext4_handle_error jbd2_journal_abort jbd2_journal_update_sb_errno jbd2_write_superblock submit_bh // LOCK B // RELEASE B do_worker throttle_work_update down_write(&t->lock) - LOCK B process_deferred_bios process_bio commit metadata_operation_failed dm_pool_abort_metadata dm_block_manager_create dm_bufio_client_create register_shrinker register_shrinker_prepared down_write(&shrinker_rwsem) - LOCK A bio_endio wait_on_buffer __wait_on_buffer Fix these by resetting dm_bufio_client without holding shrinker_rwsem. Fixes: 8111964f1b85 ("dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata") Cc: stable@vger.kernel.org Signed-off-by: Li Lingfeng Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry

2024-01-01T12:38:58+00:00

[ Upstream commit 39299bdd2546688d92ed9db4948f6219ca1b9542 ] If a key has an expiration time, then when that time passes, the key is left around for a certain amount of time before being collected (5 mins by default) so that EKEYEXPIRED can be returned instead of ENOKEY. This is a problem for DNS keys because we want to redo the DNS lookup immediately at that point. Fix this by allowing key types to be marked such that keys of that type don't have this extra period, but are reclaimed as soon as they expire and turn this on for dns_resolver-type keys. To make this easier to handle, key->expiry is changed to be permanent if TIME64_MAX rather than 0. Furthermore, give such new-style negative DNS results a 1s default expiry if no other expiry time is set rather than allowing it to stick around indefinitely. This shouldn't be zero as ls will follow a failing stat call immediately with a second with AT_SYMLINK_NOFOLLOW added. Fixes: 1a4240f4764a ("DNS: Separate out CIFS DNS Resolver code") Signed-off-by: David Howells Tested-by: Markus Suvanto cc: Wang Lei cc: Jeff Layton cc: Steve French cc: Marc Dionne cc: Jarkko Sakkinen cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: linux-cifs@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: keyrings@vger.kernel.org cc: netdev@vger.kernel.org Signed-off-by: Sasha Levin

net/mlx5: Re-organize mlx5_cmd struct

2024-01-01T12:38:55+00:00

[ Upstream commit 58db72869a9f8e01910844ca145efc2ea91bbbf9 ] Downstream patch will split mlx5_cmd_init() to probe and reload routines. As a preparation, organize mlx5_cmd struct so that any field that will be used in the reload routine are grouped at new nested struct. Signed-off-by: Shay Drory Reviewed-by: Moshe Shemesh Signed-off-by: Saeed Mahameed Stable-dep-of: 8f5100da56b3 ("net/mlx5e: Fix a race in command alloc flow") Signed-off-by: Sasha Levin

net/mlx5: Prevent high-rate FW commands from populating all slots

2024-01-01T12:38:55+00:00

[ Upstream commit 63fbae0a74c3e1df7c20c81e04353ced050d9887 ] Certain connection-based device-offload protocols (like TLS) use per-connection HW objects to track the state, maintain the context, and perform the offload properly. Some of these objects are created, modified, and destroyed via FW commands. Under high connection rate, this type of FW commands might continuously populate all slots of the FW command interface and throttle it, while starving other critical control FW commands. Limit these throttle commands to using only up to a portion (half) of the FW command interface slots. FW commands maximal rate is not hit, and the same high rate is still reached when applying this limitation. Signed-off-by: Tariq Toukan Reviewed-by: Moshe Shemesh Signed-off-by: Saeed Mahameed Stable-dep-of: 8f5100da56b3 ("net/mlx5e: Fix a race in command alloc flow") Signed-off-by: Sasha Levin

bpf: Fix prog_array_map_poke_run map poke update

2024-01-01T12:38:52+00:00

commit 4b7de801606e504e69689df71475d27e35336fb3 upstream. Lee pointed out issue found by syscaller [0] hitting BUG in prog array map poke update in prog_array_map_poke_run function due to error value returned from bpf_arch_text_poke function. There's race window where bpf_arch_text_poke can fail due to missing bpf program kallsym symbols, which is accounted for with check for -EINVAL in that BUG_ON call. The problem is that in such case we won't update the tail call jump and cause imbalance for the next tail call update check which will fail with -EBUSY in bpf_arch_text_poke. I'm hitting following race during the program load: CPU 0 CPU 1 bpf_prog_load bpf_check do_misc_fixups prog_array_map_poke_track map_update_elem bpf_fd_array_map_update_elem prog_array_map_poke_run bpf_arch_text_poke returns -EINVAL bpf_prog_kallsyms_add After bpf_arch_text_poke (CPU 1) fails to update the tail call jump, the next poke update fails on expected jump instruction check in bpf_arch_text_poke with -EBUSY and triggers the BUG_ON in prog_array_map_poke_run. Similar race exists on the program unload. Fixing this by moving the update to bpf_arch_poke_desc_update function which makes sure we call __bpf_arch_text_poke that skips the bpf address check. Each architecture has slightly different approach wrt looking up bpf address in bpf_arch_text_poke, so instead of splitting the function or adding new 'checkip' argument in previous version, it seems best to move the whole map_poke_run update as arch specific code. [0] https://syzkaller.appspot.com/bug?extid=97a4fe20470e9bc30810 Fixes: ebf7d1f508a7 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT") Reported-by: syzbot+97a4fe20470e9bc30810@syzkaller.appspotmail.com Signed-off-by: Jiri Olsa Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Cc: Lee Jones Cc: Maciej Fijalkowski Link: https://lore.kernel.org/bpf/20231206083041.1306660-2-jolsa@kernel.org Signed-off-by: Greg Kroah-Hartman

kasan: disable kasan_non_canonical_hook() for HW tags

2024-01-01T12:38:52+00:00

commit 17c17567fe510857b18fe01b7a88027600e76ac6 upstream. On arm64, building with CONFIG_KASAN_HW_TAGS now causes a compile-time error: mm/kasan/report.c: In function 'kasan_non_canonical_hook': mm/kasan/report.c:637:20: error: 'KASAN_SHADOW_OFFSET' undeclared (first use in this function) 637 | if (addr < KASAN_SHADOW_OFFSET) | ^~~~~~~~~~~~~~~~~~~ mm/kasan/report.c:637:20: note: each undeclared identifier is reported only once for each function it appears in mm/kasan/report.c:640:77: error: expected expression before ';' token 640 | orig_addr = (addr - KASAN_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT; This was caused by removing the dependency on CONFIG_KASAN_INLINE that used to prevent this from happening. Use the more specific dependency on KASAN_SW_TAGS || KASAN_GENERIC to only ignore the function for hwasan mode. Link: https://lkml.kernel.org/r/20231016200925.984439-1-arnd@kernel.org Fixes: 12ec6a919b0f ("kasan: print the original fault addr when access invalid shadow") Signed-off-by: Arnd Bergmann Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Haibo Li Cc: Kees Cook Cc: Vincenzo Frascino Cc: AngeloGioacchino Del Regno Cc: Matthias Brugger Signed-off-by: Andrew Morton Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman

mm/mglru: fix underprotected page cache

2023-12-20T16:00:26+00:00

commit 081488051d28d32569ebb7c7a23572778b2e7d57 upstream. Unmapped folios accessed through file descriptors can be underprotected. Those folios are added to the oldest generation based on: 1. The fact that they are less costly to reclaim (no need to walk the rmap and flush the TLB) and have less impact on performance (don't cause major PFs and can be non-blocking if needed again). 2. The observation that they are likely to be single-use. E.g., for client use cases like Android, its apps parse configuration files and store the data in heap (anon); for server use cases like MySQL, it reads from InnoDB files and holds the cached data for tables in buffer pools (anon). However, the oldest generation can be very short lived, and if so, it doesn't provide the PID controller with enough time to respond to a surge of refaults. (Note that the PID controller uses weighted refaults and those from evicted generations only take a half of the whole weight.) In other words, for a short lived generation, the moving average smooths out the spike quickly. To fix the problem: 1. For folios that are already on LRU, if they can be beyond the tracking range of tiers, i.e., five accesses through file descriptors, move them to the second oldest generation to give them more time to age. (Note that tiers are used by the PID controller to statistically determine whether folios accessed multiple times through file descriptors are worth protecting.) 2. When adding unmapped folios to LRU, adjust the placement of them so that they are not too close to the tail. The effect of this is similar to the above. On Android, launching 55 apps sequentially: Before After Change workingset_refault_anon 25641024 25598972 0% workingset_refault_file 115016834 106178438 -8% Link: https://lkml.kernel.org/r/20231208061407.2125867-1-yuzhao@google.com Fixes: ac35a4902374 ("mm: multi-gen LRU: minimal implementation") Signed-off-by: Yu Zhao Reported-by: Charan Teja Kalla Tested-by: Kalesh Singh Cc: T.J. Mercier Cc: Kairui Song Cc: Hillf Danton Cc: Jaroslav Pulchart Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

cred: switch to using atomic_long_t

2023-12-20T16:00:20+00:00

commit f8fa5d76925991976b3e7076f9d1052515ec1fca upstream. There are multiple ways to grab references to credentials, and the only protection we have against overflowing it is the memory required to do so. With memory sizes only moving in one direction, let's bump the reference count to 64-bit and move it outside the realm of feasibly overflowing. Signed-off-by: Jens Axboe Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

net: vlan: introduce skb_vlan_eth_hdr()

2023-12-20T16:00:16+00:00

[ Upstream commit 1f5020acb33f926030f62563c86dffca35c7b701 ] Similar to skb_eth_hdr() introduced in commit 96cc4b69581d ("macvlan: do not assume mac_header is set in macvlan_broadcast()"), let's introduce a skb_vlan_eth_hdr() helper which can be used in TX-only code paths to get to the VLAN header based on skb->data rather than based on the skb_mac_header(skb). We also consolidate the drivers that dereference skb->data to go through this helper. Signed-off-by: Vladimir Oltean Reviewed-by: Eric Dumazet Reviewed-by: Simon Horman Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller Stable-dep-of: 9fc95fe95c3e ("net: fec: correct queue selection") Signed-off-by: Sasha Levin