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2021-03-07zsmalloc: account the number of compacted pages correctlyRokudo Yan
commit 2395928158059b8f9858365fce7713ce7fef62e4 upstream. There exists multiple path may do zram compaction concurrently. 1. auto-compaction triggered during memory reclaim 2. userspace utils write zram<id>/compaction node So, multiple threads may call zs_shrinker_scan/zs_compact concurrently. But pages_compacted is a per zsmalloc pool variable and modification of the variable is not serialized(through under class->lock). There are two issues here: 1. the pages_compacted may not equal to total number of pages freed(due to concurrently add). 2. zs_shrinker_scan may not return the correct number of pages freed(issued by current shrinker). The fix is simple: 1. account the number of pages freed in zs_compact locally. 2. use actomic variable pages_compacted to accumulate total number. Link: https://lkml.kernel.org/r/20210202122235.26885-1-wu-yan@tcl.com Fixes: 860c707dca155a56 ("zsmalloc: account the number of compacted pages") Signed-off-by: Rokudo Yan <wu-yan@tcl.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-07sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs outputJoe Perches
commit 2efc459d06f1630001e3984854848a5647086232 upstream. Output defects can exist in sysfs content using sprintf and snprintf. sprintf does not know the PAGE_SIZE maximum of the temporary buffer used for outputting sysfs content and it's possible to overrun the PAGE_SIZE buffer length. Add a generic sysfs_emit function that knows that the size of the temporary buffer and ensures that no overrun is done. Add a generic sysfs_emit_at function that can be used in multiple call situations that also ensures that no overrun is done. Validate the output buffer argument to be page aligned. Validate the offset len argument to be within the PAGE_SIZE buf. Signed-off-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/884235202216d464d61ee975f7465332c86f76b2.1600285923.git.joe@perches.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04net: icmp: pass zeroed opts from icmp{,v6}_ndo_send before sendingJason A. Donenfeld
commit ee576c47db60432c37e54b1e2b43a8ca6d3a8dca upstream. The icmp{,v6}_send functions make all sorts of use of skb->cb, casting it with IPCB or IP6CB, assuming the skb to have come directly from the inet layer. But when the packet comes from the ndo layer, especially when forwarded, there's no telling what might be in skb->cb at that point. As a result, the icmp sending code risks reading bogus memory contents, which can result in nasty stack overflows such as this one reported by a user: panic+0x108/0x2ea __stack_chk_fail+0x14/0x20 __icmp_send+0x5bd/0x5c0 icmp_ndo_send+0x148/0x160 In icmp_send, skb->cb is cast with IPCB and an ip_options struct is read from it. The optlen parameter there is of particular note, as it can induce writes beyond bounds. There are quite a few ways that can happen in __ip_options_echo. For example: // sptr/skb are attacker-controlled skb bytes sptr = skb_network_header(skb); // dptr/dopt points to stack memory allocated by __icmp_send dptr = dopt->__data; // sopt is the corrupt skb->cb in question if (sopt->rr) { optlen = sptr[sopt->rr+1]; // corrupt skb->cb + skb->data soffset = sptr[sopt->rr+2]; // corrupt skb->cb + skb->data // this now writes potentially attacker-controlled data, over // flowing the stack: memcpy(dptr, sptr+sopt->rr, optlen); } In the icmpv6_send case, the story is similar, but not as dire, as only IP6CB(skb)->iif and IP6CB(skb)->dsthao are used. The dsthao case is worse than the iif case, but it is passed to ipv6_find_tlv, which does a bit of bounds checking on the value. This is easy to simulate by doing a `memset(skb->cb, 0x41, sizeof(skb->cb));` before calling icmp{,v6}_ndo_send, and it's only by good fortune and the rarity of icmp sending from that context that we've avoided reports like this until now. For example, in KASAN: BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0xa0e/0x12b0 Write of size 38 at addr ffff888006f1f80e by task ping/89 CPU: 2 PID: 89 Comm: ping Not tainted 5.10.0-rc7-debug+ #5 Call Trace: dump_stack+0x9a/0xcc print_address_description.constprop.0+0x1a/0x160 __kasan_report.cold+0x20/0x38 kasan_report+0x32/0x40 check_memory_region+0x145/0x1a0 memcpy+0x39/0x60 __ip_options_echo+0xa0e/0x12b0 __icmp_send+0x744/0x1700 Actually, out of the 4 drivers that do this, only gtp zeroed the cb for the v4 case, while the rest did not. So this commit actually removes the gtp-specific zeroing, while putting the code where it belongs in the shared infrastructure of icmp{,v6}_ndo_send. This commit fixes the issue by passing an empty IPCB or IP6CB along to the functions that actually do the work. For the icmp_send, this was already trivial, thanks to __icmp_send providing the plumbing function. For icmpv6_send, this required a tiny bit of refactoring to make it behave like the v4 case, after which it was straight forward. Fixes: a2b78e9b2cac ("sunvnet: generate ICMP PTMUD messages for smaller port MTUs") Reported-by: SinYu <liuxyon@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/netdev/CAF=yD-LOF116aHub6RMe8vB8ZpnrrnoTdqhobEx+bvoA8AsP0w@mail.gmail.com/T/ Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Link: https://lore.kernel.org/r/20210223131858.72082-1-Jason@zx2c4.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04ipv6: silence compilation warning for non-IPV6 buildsLeon Romanovsky
commit 1faba27f11c8da244e793546a1b35a9b1da8208e upstream. The W=1 compilation of allmodconfig generates the following warning: net/ipv6/icmp.c:448:6: warning: no previous prototype for 'icmp6_send' [-Wmissing-prototypes] 448 | void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info, | ^~~~~~~~~~ Fix it by providing function declaration for builds with ipv6 as a module. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04ipv6: icmp6: avoid indirect call for icmpv6_send()Eric Dumazet
commit cc7a21b6fbd945f8d8f61422ccd27203c1fafeb7 upstream. If IPv6 is builtin, we do not need an expensive indirect call to reach icmp6_send(). v2: put inline keyword before the type to avoid sparse warnings. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04icmp: allow icmpv6_ndo_send to work with CONFIG_IPV6=nJason A. Donenfeld
commit a8e41f6033a0c5633d55d6e35993c9e2005d872f upstream. The icmpv6_send function has long had a static inline implementation with an empty body for CONFIG_IPV6=n, so that code calling it doesn't need to be ifdef'd. The new icmpv6_ndo_send function, which is intended for drivers as a drop-in replacement with an identical function signature, should follow the same pattern. Without this patch, drivers that used to work with CONFIG_IPV6=n now result in a linker error. Cc: Chen Zhou <chenzhou10@huawei.com> Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 0b41713b6066 ("icmp: introduce helper for nat'd source address in network device context") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04icmp: introduce helper for nat'd source address in network device contextJason A. Donenfeld
commit 0b41713b606694257b90d61ba7e2712d8457648b upstream. This introduces a helper function to be called only by network drivers that wraps calls to icmp[v6]_send in a conntrack transformation, in case NAT has been used. We don't want to pollute the non-driver path, though, so we introduce this as a helper to be called by places that actually make use of this, as suggested by Florian. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04dm: fix deadlock when swapping to encrypted deviceMikulas Patocka
commit a666e5c05e7c4aaabb2c5d58117b0946803d03d2 upstream. The system would deadlock when swapping to a dm-crypt device. The reason is that for each incoming write bio, dm-crypt allocates memory that holds encrypted data. These excessive allocations exhaust all the memory and the result is either deadlock or OOM trigger. This patch limits the number of in-flight swap bios, so that the memory consumed by dm-crypt is limited. The limit is enforced if the target set the "limit_swap_bios" variable and if the bio has REQ_SWAP set. Non-swap bios are not affected becuase taking the semaphore would cause performance degradation. This is similar to request-based drivers - they will also block when the number of requests is over the limit. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04mm/rmap: fix potential pte_unmap on an not mapped pteMiaohe Lin
[ Upstream commit 5d5d19eda6b0ee790af89c45e3f678345be6f50f ] For PMD-mapped page (usually THP), pvmw->pte is NULL. For PTE-mapped THP, pvmw->pte is mapped. But for HugeTLB pages, pvmw->pte is not mapped and set to the relevant page table entry. So in page_vma_mapped_walk_done(), we may do pte_unmap() for HugeTLB pte which is not mapped. Fix this by checking pvmw->page against PageHuge before trying to do pte_unmap(). Link: https://lkml.kernel.org/r/20210127093349.39081-1-linmiaohe@huawei.com Fixes: ace71a19cec5 ("mm: introduce page_vma_mapped_walk()") Signed-off-by: Hongxiang Lou <louhongxiang@huawei.com> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michel Lespinasse <walken@google.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Brian Geffon <bgeffon@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04certs: Fix blacklist flag type confusionDavid Howells
[ Upstream commit 4993e1f9479a4161fd7d93e2b8b30b438f00cb0f ] KEY_FLAG_KEEP is not meant to be passed to keyring_alloc() or key_alloc(), as these only take KEY_ALLOC_* flags. KEY_FLAG_KEEP has the same value as KEY_ALLOC_BYPASS_RESTRICTION, but fortunately only key_create_or_update() uses it. LSMs using the key_alloc hook don't check that flag. KEY_FLAG_KEEP is then ignored but fortunately (again) the root user cannot write to the blacklist keyring, so it is not possible to remove a key/hash from it. Fix this by adding a KEY_ALLOC_SET_KEEP flag that tells key_alloc() to set KEY_FLAG_KEEP on the new key. blacklist_init() can then, correctly, pass this to keyring_alloc(). We can also use this in ima_mok_init() rather than setting the flag manually. Note that this doesn't fix an observable bug with the current implementation but it is required to allow addition of new hashes to the blacklist in the future without making it possible for them to be removed. Fixes: 734114f8782f ("KEYS: Add a system blacklist keyring") Reported-by: Mickaël Salaün <mic@linux.microsoft.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Mickaël Salaün <mic@linux.microsoft.com> cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04ima: Free IMA measurement buffer after kexec syscallLakshmi Ramasubramanian
[ Upstream commit f31e3386a4e92ba6eda7328cb508462956c94c64 ] IMA allocates kernel virtual memory to carry forward the measurement list, from the current kernel to the next kernel on kexec system call, in ima_add_kexec_buffer() function. This buffer is not freed before completing the kexec system call resulting in memory leak. Add ima_buffer field in "struct kimage" to store the virtual address of the buffer allocated for the IMA measurement list. Free the memory allocated for the IMA measurement list in kimage_file_post_load_cleanup() function. Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list") Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04bpf: Avoid warning when re-casting __bpf_call_base into __bpf_call_base_argsAndrii Nakryiko
[ Upstream commit 6943c2b05bf09fd5c5729f7d7d803bf3f126cb9a ] BPF interpreter uses extra input argument, so re-casts __bpf_call_base into __bpf_call_base_args. Avoid compiler warning about incompatible function prototypes by casting to void * first. Fixes: 1ea47e01ad6e ("bpf: add support for bpf_call to interpreter") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210112075520.4103414-3-andrii@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04block: split .sysfs_lock into two locksMing Lei
commit cecf5d87ff2035127bb5a9ee054d0023a4a7cad3 upstream. The kernfs built-in lock of 'kn->count' is held in sysfs .show/.store path. Meantime, inside block's .show/.store callback, q->sysfs_lock is required. However, when mq & iosched kobjects are removed via blk_mq_unregister_dev() & elv_unregister_queue(), q->sysfs_lock is held too. This way causes AB-BA lock because the kernfs built-in lock of 'kn-count' is required inside kobject_del() too, see the lockdep warning[1]. On the other hand, it isn't necessary to acquire q->sysfs_lock for both blk_mq_unregister_dev() & elv_unregister_queue() because clearing REGISTERED flag prevents storing to 'queue/scheduler' from being happened. Also sysfs write(store) is exclusive, so no necessary to hold the lock for elv_unregister_queue() when it is called in switching elevator path. So split .sysfs_lock into two: one is still named as .sysfs_lock for covering sync .store, the other one is named as .sysfs_dir_lock for covering kobjects and related status change. sysfs itself can handle the race between add/remove kobjects and showing/storing attributes under kobjects. For switching scheduler via storing to 'queue/scheduler', we use the queue flag of QUEUE_FLAG_REGISTERED with .sysfs_lock for avoiding the race, then we can avoid to hold .sysfs_lock during removing/adding kobjects. [1] lockdep warning ====================================================== WARNING: possible circular locking dependency detected 5.3.0-rc3-00044-g73277fc75ea0 #1380 Not tainted ------------------------------------------------------ rmmod/777 is trying to acquire lock: 00000000ac50e981 (kn->count#202){++++}, at: kernfs_remove_by_name_ns+0x59/0x72 but task is already holding lock: 00000000fb16ae21 (&q->sysfs_lock){+.+.}, at: blk_unregister_queue+0x78/0x10b which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&q->sysfs_lock){+.+.}: __lock_acquire+0x95f/0xa2f lock_acquire+0x1b4/0x1e8 __mutex_lock+0x14a/0xa9b blk_mq_hw_sysfs_show+0x63/0xb6 sysfs_kf_seq_show+0x11f/0x196 seq_read+0x2cd/0x5f2 vfs_read+0xc7/0x18c ksys_read+0xc4/0x13e do_syscall_64+0xa7/0x295 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (kn->count#202){++++}: check_prev_add+0x5d2/0xc45 validate_chain+0xed3/0xf94 __lock_acquire+0x95f/0xa2f lock_acquire+0x1b4/0x1e8 __kernfs_remove+0x237/0x40b kernfs_remove_by_name_ns+0x59/0x72 remove_files+0x61/0x96 sysfs_remove_group+0x81/0xa4 sysfs_remove_groups+0x3b/0x44 kobject_del+0x44/0x94 blk_mq_unregister_dev+0x83/0xdd blk_unregister_queue+0xa0/0x10b del_gendisk+0x259/0x3fa null_del_dev+0x8b/0x1c3 [null_blk] null_exit+0x5c/0x95 [null_blk] __se_sys_delete_module+0x204/0x337 do_syscall_64+0xa7/0x295 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->sysfs_lock); lock(kn->count#202); lock(&q->sysfs_lock); lock(kn->count#202); *** DEADLOCK *** 2 locks held by rmmod/777: #0: 00000000e69bd9de (&lock){+.+.}, at: null_exit+0x2e/0x95 [null_blk] #1: 00000000fb16ae21 (&q->sysfs_lock){+.+.}, at: blk_unregister_queue+0x78/0x10b stack backtrace: CPU: 0 PID: 777 Comm: rmmod Not tainted 5.3.0-rc3-00044-g73277fc75ea0 #1380 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS ?-20180724_192412-buildhw-07.phx4 Call Trace: dump_stack+0x9a/0xe6 check_noncircular+0x207/0x251 ? print_circular_bug+0x32a/0x32a ? find_usage_backwards+0x84/0xb0 check_prev_add+0x5d2/0xc45 validate_chain+0xed3/0xf94 ? check_prev_add+0xc45/0xc45 ? mark_lock+0x11b/0x804 ? check_usage_forwards+0x1ca/0x1ca __lock_acquire+0x95f/0xa2f lock_acquire+0x1b4/0x1e8 ? kernfs_remove_by_name_ns+0x59/0x72 __kernfs_remove+0x237/0x40b ? kernfs_remove_by_name_ns+0x59/0x72 ? kernfs_next_descendant_post+0x7d/0x7d ? strlen+0x10/0x23 ? strcmp+0x22/0x44 kernfs_remove_by_name_ns+0x59/0x72 remove_files+0x61/0x96 sysfs_remove_group+0x81/0xa4 sysfs_remove_groups+0x3b/0x44 kobject_del+0x44/0x94 blk_mq_unregister_dev+0x83/0xdd blk_unregister_queue+0xa0/0x10b del_gendisk+0x259/0x3fa ? disk_events_poll_msecs_store+0x12b/0x12b ? check_flags+0x1ea/0x204 ? mark_held_locks+0x1f/0x7a null_del_dev+0x8b/0x1c3 [null_blk] null_exit+0x5c/0x95 [null_blk] __se_sys_delete_module+0x204/0x337 ? free_module+0x39f/0x39f ? blkcg_maybe_throttle_current+0x8a/0x718 ? rwlock_bug+0x62/0x62 ? __blkcg_punt_bio_submit+0xd0/0xd0 ? trace_hardirqs_on_thunk+0x1a/0x20 ? mark_held_locks+0x1f/0x7a ? do_syscall_64+0x4c/0x295 do_syscall_64+0xa7/0x295 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fb696cdbe6b Code: 73 01 c3 48 8b 0d 1d 20 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 008 RSP: 002b:00007ffec9588788 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 0000559e589137c0 RCX: 00007fb696cdbe6b RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000559e58913828 RBP: 0000000000000000 R08: 00007ffec9587701 R09: 0000000000000000 R10: 00007fb696d4eae0 R11: 0000000000000206 R12: 00007ffec95889b0 R13: 00007ffec95896b3 R14: 0000559e58913260 R15: 0000559e589137c0 Cc: Christoph Hellwig <hch@infradead.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Mike Snitzer <snitzer@redhat.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> (jwang:cherry picked from commit cecf5d87ff2035127bb5a9ee054d0023a4a7cad3, adjust ctx for 4,19) Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04block: add helper for checking if queue is registeredMing Lei
commit 58c898ba370e68d39470cd0d932b524682c1f9be upstream. There are 4 users which check if queue is registered, so add one helper to check it. Cc: Christoph Hellwig <hch@infradead.org> Cc: Hannes Reinecke <hare@suse.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-23net: watchdog: hold device global xmit lock during tx disableEdwin Peer
commit 3aa6bce9af0e25b735c9c1263739a5639a336ae8 upstream. Prevent netif_tx_disable() running concurrently with dev_watchdog() by taking the device global xmit lock. Otherwise, the recommended: netif_carrier_off(dev); netif_tx_disable(dev); driver shutdown sequence can happen after the watchdog has already checked carrier, resulting in possible false alarms. This is because netif_tx_lock() only sets the frozen bit without maintaining the locks on the individual queues. Fixes: c3f26a269c24 ("netdev: Fix lockdep warnings in multiqueue configurations.") Signed-off-by: Edwin Peer <edwin.peer@broadcom.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-13memcg: fix a crash in wb_workfn when a device disappearsTheodore Ts'o
[ Upstream commit 68f23b89067fdf187763e75a56087550624fdbee ] Without memcg, there is a one-to-one mapping between the bdi and bdi_writeback structures. In this world, things are fairly straightforward; the first thing bdi_unregister() does is to shutdown the bdi_writeback structure (or wb), and part of that writeback ensures that no other work queued against the wb, and that the wb is fully drained. With memcg, however, there is a one-to-many relationship between the bdi and bdi_writeback structures; that is, there are multiple wb objects which can all point to a single bdi. There is a refcount which prevents the bdi object from being released (and hence, unregistered). So in theory, the bdi_unregister() *should* only get called once its refcount goes to zero (bdi_put will drop the refcount, and when it is zero, release_bdi gets called, which calls bdi_unregister). Unfortunately, del_gendisk() in block/gen_hd.c never got the memo about the Brave New memcg World, and calls bdi_unregister directly. It does this without informing the file system, or the memcg code, or anything else. This causes the root wb associated with the bdi to be unregistered, but none of the memcg-specific wb's are shutdown. So when one of these wb's are woken up to do delayed work, they try to dereference their wb->bdi->dev to fetch the device name, but unfortunately bdi->dev is now NULL, thanks to the bdi_unregister() called by del_gendisk(). As a result, *boom*. Fortunately, it looks like the rest of the writeback path is perfectly happy with bdi->dev and bdi->owner being NULL, so the simplest fix is to create a bdi_dev_name() function which can handle bdi->dev being NULL. This also allows us to bulletproof the writeback tracepoints to prevent them from dereferencing a NULL pointer and crashing the kernel if one is tracing with memcg's enabled, and an iSCSI device dies or a USB storage stick is pulled. The most common way of triggering this will be hotremoval of a device while writeback with memcg enabled is going on. It was triggering several times a day in a heavily loaded production environment. Google Bug Id: 145475544 Link: https://lore.kernel.org/r/20191227194829.150110-1-tytso@mit.edu Link: http://lkml.kernel.org/r/20191228005211.163952-1-tytso@mit.edu Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: Chris Mason <clm@fb.com> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13lib/string: Add strscpy_pad() functionTobin C. Harding
[ Upstream commit 458a3bf82df4fe1f951d0f52b1e0c1e9d5a88a3b ] We have a function to copy strings safely and we have a function to copy strings and zero the tail of the destination (if source string is shorter than destination buffer) but we do not have a function to do both at once. This means developers must write this themselves if they desire this functionality. This is a chore, and also leaves us open to off by one errors unnecessarily. Add a function that calls strscpy() then memset()s the tail to zero if the source string is shorter than the destination buffer. Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tobin C. Harding <tobin@kernel.org> Signed-off-by: Shuah Khan <shuah@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13SUNRPC: Move simple_get_bytes and simple_get_netobj into private headerDave Wysochanski
[ Upstream commit ba6dfce47c4d002d96cd02a304132fca76981172 ] Remove duplicated helper functions to parse opaque XDR objects and place inside new file net/sunrpc/auth_gss/auth_gss_internal.h. In the new file carry the license and copyright from the source file net/sunrpc/auth_gss/auth_gss.c. Finally, update the comment inside include/linux/sunrpc/xdr.h since lockd is not the only user of struct xdr_netobj. Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-13tracing/kprobe: Fix to support kretprobe events on unloaded modulesMasami Hiramatsu
commit 97c753e62e6c31a404183898d950d8c08d752dbd upstream. Fix kprobe_on_func_entry() returns error code instead of false so that register_kretprobe() can return an appropriate error code. append_trace_kprobe() expects the kprobe registration returns -ENOENT when the target symbol is not found, and it checks whether the target module is unloaded or not. If the target module doesn't exist, it defers to probe the target symbol until the module is loaded. However, since register_kretprobe() returns -EINVAL instead of -ENOENT in that case, it always fail on putting the kretprobe event on unloaded modules. e.g. Kprobe event: /sys/kernel/debug/tracing # echo p xfs:xfs_end_io >> kprobe_events [ 16.515574] trace_kprobe: This probe might be able to register after target module is loaded. Continue. Kretprobe event: (p -> r) /sys/kernel/debug/tracing # echo r xfs:xfs_end_io >> kprobe_events sh: write error: Invalid argument /sys/kernel/debug/tracing # cat error_log [ 41.122514] trace_kprobe: error: Failed to register probe event Command: r xfs:xfs_end_io ^ To fix this bug, change kprobe_on_func_entry() to detect symbol lookup failure and return -ENOENT in that case. Otherwise it returns -EINVAL or 0 (succeeded, given address is on the entry). Link: https://lkml.kernel.org/r/161176187132.1067016.8118042342894378981.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 59158ec4aef7 ("tracing/kprobes: Check the probe on unloaded module correctly") Reported-by: Jianlin Lv <Jianlin.Lv@arm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB pageMuchun Song
commit 585fc0d2871c9318c949fbf45b1f081edd489e96 upstream. If a new hugetlb page is allocated during fallocate it will not be marked as active (set_page_huge_active) which will result in a later isolate_huge_page failure when the page migration code would like to move that page. Such a failure would be unexpected and wrong. Only export set_page_huge_active, just leave clear_page_huge_active as static. Because there are no external users. Link: https://lkml.kernel.org/r/20210115124942.46403-3-songmuchun@bytedance.com Fixes: 70c3547e36f5 (hugetlbfs: add hugetlbfs_fallocate()) Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10genirq/msi: Activate Multi-MSI early when MSI_FLAG_ACTIVATE_EARLY is setMarc Zyngier
commit 4c457e8cb75eda91906a4f89fc39bde3f9a43922 upstream. When MSI_FLAG_ACTIVATE_EARLY is set (which is the case for PCI), __msi_domain_alloc_irqs() performs the activation of the interrupt (which in the case of PCI results in the endpoint being programmed) as soon as the interrupt is allocated. But it appears that this is only done for the first vector, introducing an inconsistent behaviour for PCI Multi-MSI. Fix it by iterating over the number of vectors allocated to each MSI descriptor. This is easily achieved by introducing a new "for_each_msi_vector" iterator, together with a tiny bit of refactoring. Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early") Reported-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210123122759.1781359-1-maz@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-10elfcore: fix building with clangArnd Bergmann
commit 6e7b64b9dd6d96537d816ea07ec26b7dedd397b9 upstream. kernel/elfcore.c only contains weak symbols, which triggers a bug with clang in combination with recordmcount: Cannot find symbol for section 2: .text. kernel/elfcore.o: failed Move the empty stubs into linux/elfcore.h as inline functions. As only two architectures use these, just use the architecture specific Kconfig symbols to key off the declaration. Link: https://lkml.kernel.org/r/20201204165742.3815221-2-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Barret Rhoden <brho@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-07kthread: Extract KTHREAD_IS_PER_CPUPeter Zijlstra
[ Upstream commit ac687e6e8c26181a33270efd1a2e2241377924b0 ] There is a need to distinguish geniune per-cpu kthreads from kthreads that happen to have a single CPU affinity. Geniune per-cpu kthreads are kthreads that are CPU affine for correctness, these will obviously have PF_KTHREAD set, but must also have PF_NO_SETAFFINITY set, lest userspace modify their affinity and ruins things. However, these two things are not sufficient, PF_NO_SETAFFINITY is also set on other tasks that have their affinities controlled through other means, like for instance workqueues. Therefore another bit is needed; it turns out kthread_create_per_cpu() already has such a bit: KTHREAD_IS_PER_CPU, which is used to make kthread_park()/kthread_unpark() work correctly. Expose this flag and remove the implicit setting of it from kthread_create_on_cpu(); the io_uring usage of it seems dubious at best. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210121103506.557620262@infradead.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-02-03iommu/vt-d: Don't dereference iommu_device if IOMMU_API is not builtBartosz Golaszewski
commit 9def3b1a07c41e21c68a0eb353e3e569fdd1d2b1 upstream. Since commit c40aaaac1018 ("iommu/vt-d: Gracefully handle DMAR units with no supported address widths") dmar.c needs struct iommu_device to be selected. We can drop this dependency by not dereferencing struct iommu_device if IOMMU_API is not selected and by reusing the information stored in iommu->drhd->ignored instead. This fixes the following build error when IOMMU_API is not selected: drivers/iommu/dmar.c: In function ‘free_iommu’: drivers/iommu/dmar.c:1139:41: error: ‘struct iommu_device’ has no member named ‘ops’ 1139 | if (intel_iommu_enabled && iommu->iommu.ops) { ^ Fixes: c40aaaac1018 ("iommu/vt-d: Gracefully handle DMAR units with no supported address widths") Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Acked-by: Lu Baolu <baolu.lu@linux.intel.com> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20201013073055.11262-1-brgl@bgdev.pl Signed-off-by: Joerg Roedel <jroedel@suse.de> [ - context change due to moving drivers/iommu/dmar.c to drivers/iommu/intel/dmar.c - set the drhr in the iommu like in upstream commit b1012ca8dc4f ("iommu/vt-d: Skip TE disabling on quirky gfx dedicated iommu") ] Signed-off-by: Filippo Sironi <sironi@amazon.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30writeback: Drop I_DIRTY_TIME_EXPIREJan Kara
commit 5fcd57505c002efc5823a7355e21f48dd02d5a51 upstream. The only use of I_DIRTY_TIME_EXPIRE is to detect in __writeback_single_inode() that inode got there because flush worker decided it's time to writeback the dirty inode time stamps (either because we are syncing or because of age). However we can detect this directly in __writeback_single_inode() and there's no need for the strange propagation with I_DIRTY_TIME_EXPIRE flag. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30futex: Add mutex around futex exitThomas Gleixner
commit 3f186d974826847a07bc7964d79ec4eded475ad9 upstream The mutex will be used in subsequent changes to replace the busy looping of a waiter when the futex owner is currently executing the exit cleanup to prevent a potential live lock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20191106224556.845798895@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30futex: Mark the begin of futex exit explicitlyThomas Gleixner
commit 18f694385c4fd77a09851fd301236746ca83f3cb upstream Instead of relying on PF_EXITING use an explicit state for the futex exit and set it in the futex exit function. This moves the smp barrier and the lock/unlock serialization into the futex code. As with the DEAD state this is restricted to the exit path as exec continues to use the same task struct. This allows to simplify that logic in a next step. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20191106224556.539409004@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30futex: Split futex_mm_release() for exit/execThomas Gleixner
commit 150d71584b12809144b8145b817e83b81158ae5f upstream To allow separate handling of the futex exit state in the futex exit code for exit and exec, split futex_mm_release() into two functions and invoke them from the corresponding exit/exec_mm_release() callsites. Preparatory only, no functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20191106224556.332094221@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30exit/exec: Seperate mm_release()Thomas Gleixner
commit 4610ba7ad877fafc0a25a30c6c82015304120426 upstream mm_release() contains the futex exit handling. mm_release() is called from do_exit()->exit_mm() and from exec()->exec_mm(). In the exit_mm() case PF_EXITING and the futex state is updated. In the exec_mm() case these states are not touched. As the futex exit code needs further protections against exit races, this needs to be split into two functions. Preparatory only, no functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20191106224556.240518241@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30futex: Replace PF_EXITPIDONE with a stateThomas Gleixner
commit 3d4775df0a89240f671861c6ab6e8d59af8e9e41 upstream The futex exit handling relies on PF_ flags. That's suboptimal as it requires a smp_mb() and an ugly lock/unlock of the exiting tasks pi_lock in the middle of do_exit() to enforce the observability of PF_EXITING in the futex code. Add a futex_state member to task_struct and convert the PF_EXITPIDONE logic over to the new state. The PF_EXITING dependency will be cleaned up in a later step. This prepares for handling various futex exit issues later. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20191106224556.149449274@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-30futex: Move futex exit handling into futex codeThomas Gleixner
commit ba31c1a48538992316cc71ce94fa9cd3e7b427c0 upstream The futex exit handling is #ifdeffed into mm_release() which is not pretty to begin with. But upcoming changes to address futex exit races need to add more functionality to this exit code. Split it out into a function, move it into futex code and make the various futex exit functions static. Preparatory only and no functional change. Folded build fix from Borislav. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20191106224556.049705556@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-23net: skbuff: disambiguate argument and member for skb_list_walk_safe helperJason A. Donenfeld
commit 5eee7bd7e245914e4e050c413dfe864e31805207 upstream. This worked before, because we made all callers name their next pointer "next". But in trying to be more "drop-in" ready, the silliness here is revealed. This commit fixes the problem by making the macro argument and the member use different names. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-23net: introduce skb_list_walk_safe for skb segment walkingJason A. Donenfeld
commit dcfea72e79b0aa7a057c8f6024169d86a1bbc84b upstream. As part of the continual effort to remove direct usage of skb->next and skb->prev, this patch adds a helper for iterating through the singly-linked variant of skb lists, which are used for lists of GSO packet. The name "skb_list_..." has been chosen to match the existing function, "kfree_skb_list, which also operates on these singly-linked lists, and the "..._walk_safe" part is the same idiom as elsewhere in the kernel. This patch removes the helper from wireguard and puts it into linux/skbuff.h, while making it a bit more robust for general usage. In particular, parenthesis are added around the macro argument usage, and it now accounts for trying to iterate through an already-null skb pointer, which will simply run the iteration zero times. This latter enhancement means it can be used to replace both do { ... } while and while (...) open-coded idioms. This should take care of these three possible usages, which match all current methods of iterations. skb_list_walk_safe(segs, skb, next) { ... } skb_list_walk_safe(skb, skb, next) { ... } skb_list_walk_safe(segs, skb, segs) { ... } Gcc appears to generate efficient code for each of these. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net> [ Just the skbuff.h changes for backporting - gregkh] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-23dm integrity: fix flush with external metadata deviceMikulas Patocka
commit 9b5948267adc9e689da609eb61cf7ed49cae5fa8 upstream. With external metadata device, flush requests are not passed down to the data device. Fix this by submitting the flush request in dm_integrity_flush_buffers. In order to not degrade performance, we overlap the data device flush with the metadata device flush. Reported-by: Lukas Straub <lukasstraub2@web.de> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-23compiler.h: Raise minimum version of GCC to 5.1 for arm64Will Deacon
commit dca5244d2f5b94f1809f0c02a549edf41ccd5493 upstream. GCC versions >= 4.9 and < 5.1 have been shown to emit memory references beyond the stack pointer, resulting in memory corruption if an interrupt is taken after the stack pointer has been adjusted but before the reference has been executed. This leads to subtle, infrequent data corruption such as the EXT4 problems reported by Russell King at the link below. Life is too short for buggy compilers, so raise the minimum GCC version required by arm64 to 5.1. Reported-by: Russell King <linux@armlinux.org.uk> Suggested-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@vger.kernel.org> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Florian Weimer <fweimer@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20210105154726.GD1551@shell.armlinux.org.uk Link: https://lore.kernel.org/r/20210112224832.10980-1-will@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [will: backport to 4.19.y/5.4.y] Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-19ACPI: scan: add stub acpi_create_platform_device() for !CONFIG_ACPIShawn Guo
[ Upstream commit ee61cfd955a64a58ed35cbcfc54068fcbd486945 ] It adds a stub acpi_create_platform_device() for !CONFIG_ACPI build, so that caller doesn't have to deal with !CONFIG_ACPI build issue. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-12proc: fix lookup in /proc/net subdirectories after setns(2)Alexey Dobriyan
[ Upstream commit c6c75deda81344c3a95d1d1f606d5cee109e5d54 ] Commit 1fde6f21d90f ("proc: fix /proc/net/* after setns(2)") only forced revalidation of regular files under /proc/net/ However, /proc/net/ is unusual in the sense of /proc/net/foo handlers take netns pointer from parent directory which is old netns. Steps to reproduce: (void)open("/proc/net/sctp/snmp", O_RDONLY); unshare(CLONE_NEWNET); int fd = open("/proc/net/sctp/snmp", O_RDONLY); read(fd, &c, 1); Read will read wrong data from original netns. Patch forces lookup on every directory under /proc/net . Link: https://lkml.kernel.org/r/20201205160916.GA109739@localhost.localdomain Fixes: 1da4d377f943 ("proc: revalidate misc dentries") Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reported-by: "Rantala, Tommi T. (Nokia - FI/Espoo)" <tommi.t.rantala@nokia.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-09kdev_t: always inline major/minor helper functionsJosh Poimboeuf
commit aa8c7db494d0a83ecae583aa193f1134ef25d506 upstream. Silly GCC doesn't always inline these trivial functions. Fixes the following warning: arch/x86/kernel/sys_ia32.o: warning: objtool: cp_stat64()+0xd8: call to new_encode_dev() with UACCESS enabled Link: https://lkml.kernel.org/r/984353b44a4484d86ba9f73884b7306232e25e30.1608737428.git.jpoimboe@redhat.com Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Reported-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> [build-tested] Cc: Peter Zijlstra <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-06of: fix linker-section match-table corruptionJohan Hovold
commit 5812b32e01c6d86ba7a84110702b46d8a8531fe9 upstream. Specify type alignment when declaring linker-section match-table entries to prevent gcc from increasing alignment and corrupting the various tables with padding (e.g. timers, irqchips, clocks, reserved memory). This is specifically needed on x86 where gcc (typically) aligns larger objects like struct of_device_id with static extent on 32-byte boundaries which at best prevents matching on anything but the first entry. Specifying alignment when declaring variables suppresses this optimisation. Here's a 64-bit example where all entries are corrupt as 16 bytes of padding has been inserted before the first entry: ffffffff8266b4b0 D __clk_of_table ffffffff8266b4c0 d __of_table_fixed_factor_clk ffffffff8266b5a0 d __of_table_fixed_clk ffffffff8266b680 d __clk_of_table_sentinel And here's a 32-bit example where the 8-byte-aligned table happens to be placed on a 32-byte boundary so that all but the first entry are corrupt due to the 28 bytes of padding inserted between entries: 812b3ec0 D __irqchip_of_table 812b3ec0 d __of_table_irqchip1 812b3fa0 d __of_table_irqchip2 812b4080 d __of_table_irqchip3 812b4160 d irqchip_of_match_end Verified on x86 using gcc-9.3 and gcc-4.9 (which uses 64-byte alignment), and on arm using gcc-7.2. Note that there are no in-tree users of these tables on x86 currently (even if they are included in the image). Fixes: 54196ccbe0ba ("of: consolidate linker section OF match table declarations") Fixes: f6e916b82022 ("irqchip: add basic infrastructure") Cc: stable <stable@vger.kernel.org> # 3.9 Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20201123102319.8090-2-johan@kernel.org [ johan: adjust context to 5.4 ] Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-06fscrypt: add fscrypt_is_nokey_name()Eric Biggers
commit 159e1de201b6fca10bfec50405a3b53a561096a8 upstream. It's possible to create a duplicate filename in an encrypted directory by creating a file concurrently with adding the encryption key. Specifically, sys_open(O_CREAT) (or sys_mkdir(), sys_mknod(), or sys_symlink()) can lookup the target filename while the directory's encryption key hasn't been added yet, resulting in a negative no-key dentry. The VFS then calls ->create() (or ->mkdir(), ->mknod(), or ->symlink()) because the dentry is negative. Normally, ->create() would return -ENOKEY due to the directory's key being unavailable. However, if the key was added between the dentry lookup and ->create(), then the filesystem will go ahead and try to create the file. If the target filename happens to already exist as a normal name (not a no-key name), a duplicate filename may be added to the directory. In order to fix this, we need to fix the filesystems to prevent ->create(), ->mkdir(), ->mknod(), and ->symlink() on no-key names. (->rename() and ->link() need it too, but those are already handled correctly by fscrypt_prepare_rename() and fscrypt_prepare_link().) In preparation for this, add a helper function fscrypt_is_nokey_name() that filesystems can use to do this check. Use this helper function for the existing checks that fs/crypto/ does for rename and link. Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201118075609.120337-2-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30fix namespaced fscaps when !CONFIG_SECURITYSerge Hallyn
[ Upstream commit ed9b25d1970a4787ac6a39c2091e63b127ecbfc1 ] Namespaced file capabilities were introduced in 8db6c34f1dbc . When userspace reads an xattr for a namespaced capability, a virtualized representation of it is returned if the caller is in a user namespace owned by the capability's owning rootid. The function which performs this virtualization was not hooked up if CONFIG_SECURITY=n. Therefore in that case the original xattr was shown instead of the virtualized one. To test this using libcap-bin (*1), $ v=$(mktemp) $ unshare -Ur setcap cap_sys_admin-eip $v $ unshare -Ur setcap -v cap_sys_admin-eip $v /tmp/tmp.lSiIFRvt8Y: OK "setcap -v" verifies the values instead of setting them, and will check whether the rootid value is set. Therefore, with this bug un-fixed, and with CONFIG_SECURITY=n, setcap -v will fail: $ v=$(mktemp) $ unshare -Ur setcap cap_sys_admin=eip $v $ unshare -Ur setcap -v cap_sys_admin=eip $v nsowner[got=1000, want=0],/tmp/tmp.HHDiOOl9fY differs in [] Fix this bug by calling cap_inode_getsecurity() in security_inode_getsecurity() instead of returning -EOPNOTSUPP, when CONFIG_SECURITY=n. *1 - note, if libcap is too old for getcap to have the '-n' option, then use verify-caps instead. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=209689 Cc: Hervé Guillemet <herve@guillemet.org> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Serge Hallyn <shallyn@cisco.com> Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Signed-off-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30seq_buf: Avoid type mismatch for seq_buf_initArnd Bergmann
[ Upstream commit d9a9280a0d0ae51dc1d4142138b99242b7ec8ac6 ] Building with W=2 prints a number of warnings for one function that has a pointer type mismatch: linux/seq_buf.h: In function 'seq_buf_init': linux/seq_buf.h:35:12: warning: pointer targets in assignment from 'unsigned char *' to 'char *' differ in signedness [-Wpointer-sign] Change the type in the function prototype according to the type in the structure. Link: https://lkml.kernel.org/r/20201026161108.3707783-1-arnd@kernel.org Fixes: 9a7777935c34 ("tracing: Convert seq_buf fields to be like seq_file fields") Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30SUNRPC: xprt_load_transport() needs to support the netid "rdma6"Trond Myklebust
[ Upstream commit d5aa6b22e2258f05317313ecc02efbb988ed6d38 ] According to RFC5666, the correct netid for an IPv6 addressed RDMA transport is "rdma6", which we've supported as a mount option since Linux-4.7. The problem is when we try to load the module "xprtrdma6", that will fail, since there is no modulealias of that name. Fixes: 181342c5ebe8 ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30netfilter: x_tables: Switch synchronization to RCUSubash Abhinov Kasiviswanathan
[ Upstream commit cc00bcaa589914096edef7fb87ca5cee4a166b5c ] When running concurrent iptables rules replacement with data, the per CPU sequence count is checked after the assignment of the new information. The sequence count is used to synchronize with the packet path without the use of any explicit locking. If there are any packets in the packet path using the table information, the sequence count is incremented to an odd value and is incremented to an even after the packet process completion. The new table value assignment is followed by a write memory barrier so every CPU should see the latest value. If the packet path has started with the old table information, the sequence counter will be odd and the iptables replacement will wait till the sequence count is even prior to freeing the old table info. However, this assumes that the new table information assignment and the memory barrier is actually executed prior to the counter check in the replacement thread. If CPU decides to execute the assignment later as there is no user of the table information prior to the sequence check, the packet path in another CPU may use the old table information. The replacement thread would then free the table information under it leading to a use after free in the packet processing context- Unable to handle kernel NULL pointer dereference at virtual address 000000000000008e pc : ip6t_do_table+0x5d0/0x89c lr : ip6t_do_table+0x5b8/0x89c ip6t_do_table+0x5d0/0x89c ip6table_filter_hook+0x24/0x30 nf_hook_slow+0x84/0x120 ip6_input+0x74/0xe0 ip6_rcv_finish+0x7c/0x128 ipv6_rcv+0xac/0xe4 __netif_receive_skb+0x84/0x17c process_backlog+0x15c/0x1b8 napi_poll+0x88/0x284 net_rx_action+0xbc/0x23c __do_softirq+0x20c/0x48c This could be fixed by forcing instruction order after the new table information assignment or by switching to RCU for the synchronization. Fixes: 80055dab5de0 ("netfilter: x_tables: make xt_replace_table wait until old rules are not used anymore") Reported-by: Sean Tranchetti <stranche@codeaurora.org> Reported-by: kernel test robot <lkp@intel.com> Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30USB: UAS: introduce a quirk to set no_write_sameOliver Neukum
commit 8010622c86ca5bb44bc98492f5968726fc7c7a21 upstream. UAS does not share the pessimistic assumption storage is making that devices cannot deal with WRITE_SAME. A few devices supported by UAS, are reported to not deal well with WRITE_SAME. Those need a quirk. Add it to the device that needs it. Reported-by: David C. Partridge <david.partridge@perdrix.co.uk> Signed-off-by: Oliver Neukum <oneukum@suse.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201209152639.9195-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30compiler.h: fix barrier_data() on clangArvind Sankar
commit 3347acc6fcd4ee71ad18a9ff9d9dac176b517329 upstream. Commit 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") neglected to copy barrier_data() from compiler-gcc.h into compiler-clang.h. The definition in compiler-gcc.h was really to work around clang's more aggressive optimization, so this broke barrier_data() on clang, and consequently memzero_explicit() as well. For example, this results in at least the memzero_explicit() call in lib/crypto/sha256.c:sha256_transform() being optimized away by clang. Fix this by moving the definition of barrier_data() into compiler.h. Also move the gcc/clang definition of barrier() into compiler.h, __memory_barrier() is icc-specific (and barrier() is already defined using it in compiler-intel.h) and doesn't belong in compiler.h. [rdunlap@infradead.org: fix ALPHA builds when SMP is not enabled] Link: https://lkml.kernel.org/r/20201101231835.4589-1-rdunlap@infradead.org Fixes: 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201014212631.207844-1-nivedita@alum.mit.edu Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [nd: backport to account for missing commit e506ea451254a ("compiler.h: Split {READ,WRITE}_ONCE definitions out into rwonce.h") commit d08b9f0ca6605 ("scs: Add support for Clang's Shadow Call Stack (SCS)") commit a3f8a30f3f00 ("Compiler Attributes: use feature checks instead of version checks")] Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30kbuild: avoid static_assert for genksymsArnd Bergmann
commit 14dc3983b5dff513a90bd5a8cc90acaf7867c3d0 upstream. genksyms does not know or care about the _Static_assert() built-in, and sometimes falls back to ignoring the later symbols, which causes undefined behavior such as WARNING: modpost: EXPORT symbol "ethtool_set_ethtool_phy_ops" [vmlinux] version generation failed, symbol will not be versioned. ld: net/ethtool/common.o: relocation R_AARCH64_ABS32 against `__crc_ethtool_set_ethtool_phy_ops' can not be used when making a shared object net/ethtool/common.o:(_ftrace_annotated_branch+0x0): dangerous relocation: unsupported relocation Redefine static_assert for genksyms to avoid that. Link: https://lkml.kernel.org/r/20201203230955.1482058-1-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Ard Biesheuvel <ardb@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Kees Cook <keescook@chromium.org> Cc: Rikard Falkeborn <rikard.falkeborn@gmail.com> Cc: Marco Elver <elver@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11spi: Introduce device-managed SPI controller allocationLukas Wunner
[ Upstream commit 5e844cc37a5cbaa460e68f9a989d321d63088a89 ] SPI driver probing currently comprises two steps, whereas removal comprises only one step: spi_alloc_master() spi_register_controller() spi_unregister_controller() That's because spi_unregister_controller() calls device_unregister() instead of device_del(), thereby releasing the reference on the spi_controller which was obtained by spi_alloc_master(). An SPI driver's private data is contained in the same memory allocation as the spi_controller struct. Thus, once spi_unregister_controller() has been called, the private data is inaccessible. But some drivers need to access it after spi_unregister_controller() to perform further teardown steps. Introduce devm_spi_alloc_master() and devm_spi_alloc_slave(), which release a reference on the spi_controller struct only after the driver has unbound, thereby keeping the memory allocation accessible. Change spi_unregister_controller() to not release a reference if the spi_controller was allocated by one of these new devm functions. The present commit is small enough to be backportable to stable. It allows fixing drivers which use the private data in their ->remove() hook after it's been freed. It also allows fixing drivers which neglect to release a reference on the spi_controller in the probe error path. Long-term, most SPI drivers shall be moved over to the devm functions introduced herein. The few that can't shall be changed in a treewide commit to explicitly release the last reference on the controller. That commit shall amend spi_unregister_controller() to no longer release a reference, thereby completing the migration. As a result, the behaviour will be less surprising and more consistent with subsystems such as IIO, which also includes the private data in the allocation of the generic iio_dev struct, but calls device_del() in iio_device_unregister(). Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/272bae2ef08abd21388c98e23729886663d19192.1605121038.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11tty: Fix ->session lockingJann Horn
commit c8bcd9c5be24fb9e6132e97da5a35e55a83e36b9 upstream. Currently, locking of ->session is very inconsistent; most places protect it using the legacy tty mutex, but disassociate_ctty(), __do_SAK(), tiocspgrp() and tiocgsid() don't. Two of the writers hold the ctrl_lock (because they already need it for ->pgrp), but __proc_set_tty() doesn't do that yet. On a PREEMPT=y system, an unprivileged user can theoretically abuse this broken locking to read 4 bytes of freed memory via TIOCGSID if tiocgsid() is preempted long enough at the right point. (Other things might also go wrong, especially if root-only ioctls are involved; I'm not sure about that.) Change the locking on ->session such that: - tty_lock() is held by all writers: By making disassociate_ctty() hold it. This should be fine because the same lock can already be taken through the call to tty_vhangup_session(). The tricky part is that we need to shorten the area covered by siglock to be able to take tty_lock() without ugly retry logic; as far as I can tell, this should be fine, since nothing in the signal_struct is touched in the `if (tty)` branch. - ctrl_lock is held by all writers: By changing __proc_set_tty() to hold the lock a little longer. - All readers that aren't holding tty_lock() hold ctrl_lock: By adding locking to tiocgsid() and __do_SAK(), and expanding the area covered by ctrl_lock in tiocspgrp(). Cc: stable@kernel.org Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-02netfilter: clear skb->next in NF_HOOK_LIST()Cong Wang
NF_HOOK_LIST() uses list_del() to remove skb from the linked list, however, it is not sufficient as skb->next still points to other skb. We should just call skb_list_del_init() to clear skb->next, like the rest places which using skb list. This has been fixed in upstream by commit ca58fbe06c54 ("netfilter: add and use nf_hook_slow_list()"). Fixes: 9f17dbf04ddf ("netfilter: fix use-after-free in NF_HOOK_LIST") Reported-by: liuzx@knownsec.com Tested-by: liuzx@knownsec.com Cc: Florian Westphal <fw@strlen.de> Cc: Edward Cree <ecree@solarflare.com> Cc: stable@vger.kernel.org # between 4.19 and 5.4 Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>