August 2025 - Linux-stable-mirror

+ kho-init-new_physxa-phys_bits-to-fix-lockdep.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: kho: init new_physxa->phys_bits to fix lockdep has been added to the -mm mm-hotfixes-unstable branch. Its filename is kho-init-new_physxa-phys_bits-to-fix-lockdep.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Pasha Tatashin <pasha.tatashin(a)soleen.com> Subject: kho: init new_physxa->phys_bits to fix lockdep Date: Fri, 8 Aug 2025 20:18:02 +0000 Patch series "Several KHO Hotfixes". Three unrelated fixes for Kexec Handover. This patch (of 3): Lockdep shows the following warning: INFO: trying to register non-static key. The code is fine but needs lockdep annotation, or maybe you didn't initialize this object before use? turning off the locking correctness validator. [<ffffffff810133a6>] dump_stack_lvl+0x66/0xa0 [<ffffffff8136012c>] assign_lock_key+0x10c/0x120 [<ffffffff81358bb4>] register_lock_class+0xf4/0x2f0 [<ffffffff813597ff>] __lock_acquire+0x7f/0x2c40 [<ffffffff81360cb0>] ? __pfx_hlock_conflict+0x10/0x10 [<ffffffff811707be>] ? native_flush_tlb_global+0x8e/0xa0 [<ffffffff8117096e>] ? __flush_tlb_all+0x4e/0xa0 [<ffffffff81172fc2>] ? __kernel_map_pages+0x112/0x140 [<ffffffff813ec327>] ? xa_load_or_alloc+0x67/0xe0 [<ffffffff81359556>] lock_acquire+0xe6/0x280 [<ffffffff813ec327>] ? xa_load_or_alloc+0x67/0xe0 [<ffffffff8100b9e0>] _raw_spin_lock+0x30/0x40 [<ffffffff813ec327>] ? xa_load_or_alloc+0x67/0xe0 [<ffffffff813ec327>] xa_load_or_alloc+0x67/0xe0 [<ffffffff813eb4c0>] kho_preserve_folio+0x90/0x100 [<ffffffff813ebb7f>] __kho_finalize+0xcf/0x400 [<ffffffff813ebef4>] kho_finalize+0x34/0x70 This is becase xa has its own lock, that is not initialized in xa_load_or_alloc. Modifiy __kho_preserve_order(), to properly call xa_init(&new_physxa->phys_bits); Link: https://lkml.kernel.org/r/20250808201804.772010-2-pasha.tatashin@soleen.com Fixes: fc33e4b44b27 ("kexec: enable KHO support for memory preservation") Signed-off-by: Pasha Tatashin <pasha.tatashin(a)soleen.com> Acked-by: Mike Rapoport (Microsoft) <rppt(a)kernel.org> Cc: Alexander Graf <graf(a)amazon.com> Cc: Arnd Bergmann <arnd(a)arndb.de> Cc: Baoquan He <bhe(a)redhat.com> Cc: Changyuan Lyu <changyuanl(a)google.com> Cc: Coiby Xu <coxu(a)redhat.com> Cc: Dave Vasilevsky <dave(a)vasilevsky.ca> Cc: Eric Biggers <ebiggers(a)google.com> Cc: Kees Cook <kees(a)kernel.org> Cc: Pratyush Yadav <pratyush(a)kernel.org> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- kernel/kexec_handover.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) --- a/kernel/kexec_handover.c~kho-init-new_physxa-phys_bits-to-fix-lockdep +++ a/kernel/kexec_handover.c @@ -144,14 +144,34 @@ static int __kho_preserve_order(struct k unsigned int order) { struct kho_mem_phys_bits *bits; - struct kho_mem_phys *physxa; + struct kho_mem_phys *physxa, *new_physxa; const unsigned long pfn_high = pfn >> order; might_sleep(); - physxa = xa_load_or_alloc(&track->orders, order, sizeof(*physxa)); - if (IS_ERR(physxa)) - return PTR_ERR(physxa); + physxa = xa_load(&track->orders, order); + if (!physxa) { + int err; + + new_physxa = kzalloc(sizeof(*physxa), GFP_KERNEL); + if (!new_physxa) + return -ENOMEM; + + xa_init(&new_physxa->phys_bits); + physxa = xa_cmpxchg(&track->orders, order, NULL, new_physxa, + GFP_KERNEL); + + err = xa_err(physxa); + if (err || physxa) { + xa_destroy(&new_physxa->phys_bits); + kfree(new_physxa); + + if (err) + return err; + } else { + physxa = new_physxa; + } + } bits = xa_load_or_alloc(&physxa->phys_bits, pfn_high / PRESERVE_BITS, sizeof(*bits)); _ Patches currently in -mm which might be from pasha.tatashin(a)soleen.com are kho-init-new_physxa-phys_bits-to-fix-lockdep.patch kho-mm-dont-allow-deferred-struct-page-with-kho.patch kho-warn-if-kho-is-disabled-due-to-an-error.patch

2 months, 3 weeks

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Re: [PATCH 2/2] mm/damon/core : fix commit_ops_filters by using correct nth function

by SeongJae Park

On Sat, 9 Aug 2025 04:55:18 +0900 Sang-Heon Jeon <ekffu200098(a)gmail.com> wrote: > damos_commit_ops_filters() incorrectly uses damos_nth_filter() which > iterates core_filters. As a result, performing a commit unintentionally > corrupts ops_filters. > > Add damos_nth_ops_filter() which iterates ops_filters. Use this function > to fix issues caused by wrong iteration. Thank you for finding and fixing this bug! Since this bug is better to be fixed as soon as possible, could you please send the next version of this patch as an individual one, rather than as a part of this patchset? > > Signed-off-by: Sang-Heon Jeon <ekffu200098(a)gmail.com> Let's add below for stable kernel maintainers[1]. Fixes: 3607cc590f18 ("mm/damon/core: support committing ops_filters") # 6.15.x Cc: stable(a)vger.kernel.org And the fix looks good to me, so Reviewed-by: SeongJae Park <sj(a)kernel.org> [...] [1] https://docs.kernel.org/process/stable-kernel-rules.html Thanks, SJ

2 months, 3 weeks

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[PATCH linux-6.12.y 1/2] selftests/bpf: Add a test for arena range tree algorithm

by Yifei Liu

From: Alexei Starovoitov <ast(a)kernel.org> [ Upstream commit e58358afa84e8e271a296459d35d1715c7572013 ] Add a test that verifies specific behavior of arena range tree algorithm and adjust existing big_alloc1 test due to use of global data in arena. Signed-off-by: Alexei Starovoitov <ast(a)kernel.org> Signed-off-by: Andrii Nakryiko <andrii(a)kernel.org> Acked-by: Kumar Kartikeya Dwivedi <memxor(a)gmail.com> Link: https://lore.kernel.org/bpf/20241108025616.17625-3-alexei.starovoitov@gmail… [Yifei: This commit fixes the failure of verifier_arena_large test over 64k page size kernels. This commit also introduce some new tests targeting the new feature, arena range tree algorithm, which is not in linux-6.12.y, I just comment out the test headers so that it would not be run here. If this feature is introduced later, we can just uncomment those two lines.] Signed-off-by: Yifei Liu <yifei.l.liu(a)oracle.com> --- .../bpf/progs/verifier_arena_large.c | 110 +++++++++++++++++- 1 file changed, 108 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/bpf/progs/verifier_arena_large.c b/tools/testing/selftests/bpf/progs/verifier_arena_large.c index 6065f862d964..f318675814c6 100644 --- a/tools/testing/selftests/bpf/progs/verifier_arena_large.c +++ b/tools/testing/selftests/bpf/progs/verifier_arena_large.c @@ -29,12 +29,12 @@ int big_alloc1(void *ctx) if (!page1) return 1; *page1 = 1; - page2 = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE - PAGE_SIZE, + page2 = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE - PAGE_SIZE * 2, 1, NUMA_NO_NODE, 0); if (!page2) return 2; *page2 = 2; - no_page = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE, + no_page = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE - PAGE_SIZE, 1, NUMA_NO_NODE, 0); if (no_page) return 3; @@ -66,4 +66,110 @@ int big_alloc1(void *ctx) #endif return 0; } + +#if defined(__BPF_FEATURE_ADDR_SPACE_CAST) +#define PAGE_CNT 100 +__u8 __arena * __arena page[PAGE_CNT]; /* occupies the first page */ +__u8 __arena *base; + +/* + * Check that arena's range_tree algorithm allocates pages sequentially + * on the first pass and then fills in all gaps on the second pass. + */ +__noinline int alloc_pages(int page_cnt, int pages_atonce, bool first_pass, + int max_idx, int step) +{ + __u8 __arena *pg; + int i, pg_idx; + + for (i = 0; i < page_cnt; i++) { + pg = bpf_arena_alloc_pages(&arena, NULL, pages_atonce, + NUMA_NO_NODE, 0); + if (!pg) + return step; + pg_idx = (pg - base) / PAGE_SIZE; + if (first_pass) { + /* Pages must be allocated sequentially */ + if (pg_idx != i) + return step + 100; + } else { + /* Allocator must fill into gaps */ + if (pg_idx >= max_idx || (pg_idx & 1)) + return step + 200; + } + *pg = pg_idx; + page[pg_idx] = pg; + cond_break; + } + return 0; +} + +//SEC("syscall") +//__success __retval(0) +int big_alloc2(void *ctx) +{ + __u8 __arena *pg; + int i, err; + + base = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0); + if (!base) + return 1; + bpf_arena_free_pages(&arena, (void __arena *)base, 1); + + err = alloc_pages(PAGE_CNT, 1, true, PAGE_CNT, 2); + if (err) + return err; + + /* Clear all even pages */ + for (i = 0; i < PAGE_CNT; i += 2) { + pg = page[i]; + if (*pg != i) + return 3; + bpf_arena_free_pages(&arena, (void __arena *)pg, 1); + page[i] = NULL; + cond_break; + } + + /* Allocate into freed gaps */ + err = alloc_pages(PAGE_CNT / 2, 1, false, PAGE_CNT, 4); + if (err) + return err; + + /* Free pairs of pages */ + for (i = 0; i < PAGE_CNT; i += 4) { + pg = page[i]; + if (*pg != i) + return 5; + bpf_arena_free_pages(&arena, (void __arena *)pg, 2); + page[i] = NULL; + page[i + 1] = NULL; + cond_break; + } + + /* Allocate 2 pages at a time into freed gaps */ + err = alloc_pages(PAGE_CNT / 4, 2, false, PAGE_CNT, 6); + if (err) + return err; + + /* Check pages without freeing */ + for (i = 0; i < PAGE_CNT; i += 2) { + pg = page[i]; + if (*pg != i) + return 7; + cond_break; + } + + pg = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0); + + if (!pg) + return 8; + /* + * The first PAGE_CNT pages are occupied. The new page + * must be above. + */ + if ((pg - base) / PAGE_SIZE < PAGE_CNT) + return 9; + return 0; +} +#endif char _license[] SEC("license") = "GPL"; -- 2.46.0

2 months, 3 weeks

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[PATCH net,v2] hv_netvsc: Fix panic during namespace deletion with VF

by Haiyang Zhang

From: Haiyang Zhang <haiyangz(a)microsoft.com> The existing code move the VF NIC to new namespace when NETDEV_REGISTER is received on netvsc NIC. During deletion of the namespace, default_device_exit_batch() >> default_device_exit_net() is called. When netvsc NIC is moved back and registered to the default namespace, it automatically brings VF NIC back to the default namespace. This will cause the default_device_exit_net() >> for_each_netdev_safe loop unable to detect the list end, and hit NULL ptr: [ 231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0 [ 231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 231.450246] #PF: supervisor read access in kernel mode [ 231.450579] #PF: error_code(0x0000) - not-present page [ 231.450916] PGD 17b8a8067 P4D 0 [ 231.451163] Oops: Oops: 0000 [#1] SMP NOPTI [ 231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY [ 231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 231.452692] Workqueue: netns cleanup_net [ 231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0 [ 231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00 [ 231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246 [ 231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb [ 231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564 [ 231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000 [ 231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340 [ 231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340 [ 231.457161] FS: 0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000 [ 231.457707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0 [ 231.458434] Call Trace: [ 231.458600] <TASK> [ 231.458777] ops_undo_list+0x100/0x220 [ 231.459015] cleanup_net+0x1b8/0x300 [ 231.459285] process_one_work+0x184/0x340 To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid changing the netdev list when default_device_exit_net() is using it. Cc: stable(a)vger.kernel.org Fixes: 4c262801ea60 ("hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event") Signed-off-by: Haiyang Zhang <haiyangz(a)microsoft.com> --- v2: Moved the ns change to a workqueue as suggested by Jakub Kicinski. --- drivers/net/hyperv/hyperv_net.h | 3 +++ drivers/net/hyperv/netvsc_drv.c | 29 ++++++++++++++++++++++++++++- 2 files changed, 31 insertions(+), 1 deletion(-) diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index cb6f5482d203..7397c693f984 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -1061,6 +1061,7 @@ struct net_device_context { struct net_device __rcu *vf_netdev; struct netvsc_vf_pcpu_stats __percpu *vf_stats; struct delayed_work vf_takeover; + struct delayed_work vfns_work; /* 1: allocated, serial number is valid. 0: not allocated */ u32 vf_alloc; @@ -1075,6 +1076,8 @@ struct net_device_context { struct netvsc_device_info *saved_netvsc_dev_info; }; +void netvsc_vfns_work(struct work_struct *w); + /* Azure hosts don't support non-TCP port numbers in hashing for fragmented * packets. We can use ethtool to change UDP hash level when necessary. */ diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index f44753756358..39c892e46cb0 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -2522,6 +2522,7 @@ static int netvsc_probe(struct hv_device *dev, spin_lock_init(&net_device_ctx->lock); INIT_LIST_HEAD(&net_device_ctx->reconfig_events); INIT_DELAYED_WORK(&net_device_ctx->vf_takeover, netvsc_vf_setup); + INIT_DELAYED_WORK(&net_device_ctx->vfns_work, netvsc_vfns_work); net_device_ctx->vf_stats = netdev_alloc_pcpu_stats(struct netvsc_vf_pcpu_stats); @@ -2666,6 +2667,8 @@ static void netvsc_remove(struct hv_device *dev) cancel_delayed_work_sync(&ndev_ctx->dwork); rtnl_lock(); + cancel_delayed_work_sync(&ndev_ctx->vfns_work); + nvdev = rtnl_dereference(ndev_ctx->nvdev); if (nvdev) { cancel_work_sync(&nvdev->subchan_work); @@ -2707,6 +2710,7 @@ static int netvsc_suspend(struct hv_device *dev) cancel_delayed_work_sync(&ndev_ctx->dwork); rtnl_lock(); + cancel_delayed_work_sync(&ndev_ctx->vfns_work); nvdev = rtnl_dereference(ndev_ctx->nvdev); if (nvdev == NULL) { @@ -2800,6 +2804,27 @@ static void netvsc_event_set_vf_ns(struct net_device *ndev) } } +void netvsc_vfns_work(struct work_struct *w) +{ + struct net_device_context *ndev_ctx = + container_of(w, struct net_device_context, vfns_work.work); + struct net_device *ndev; + + if (!rtnl_trylock()) { + schedule_delayed_work(&ndev_ctx->vfns_work, 1); + return; + } + + ndev = hv_get_drvdata(ndev_ctx->device_ctx); + if (!ndev) + goto out; + + netvsc_event_set_vf_ns(ndev); + +out: + rtnl_unlock(); +} + /* * On Hyper-V, every VF interface is matched with a corresponding * synthetic interface. The synthetic interface is presented first @@ -2810,10 +2835,12 @@ static int netvsc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *event_dev = netdev_notifier_info_to_dev(ptr); + struct net_device_context *ndev_ctx; int ret = 0; if (event_dev->netdev_ops == &device_ops && event == NETDEV_REGISTER) { - netvsc_event_set_vf_ns(event_dev); + ndev_ctx = netdev_priv(event_dev); + schedule_delayed_work(&ndev_ctx->vfns_work, 0); return NOTIFY_DONE; } -- 2.34.1

2 months, 3 weeks

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[PATCH AUTOSEL 6.16-6.6] exfat: add cluster chain loop check for dir

by Sasha Levin

From: Yuezhang Mo <Yuezhang.Mo(a)sony.com> [ Upstream commit 99f9a97dce39ad413c39b92c90393bbd6778f3fd ] An infinite loop may occur if the following conditions occur due to file system corruption. (1) Condition for exfat_count_dir_entries() to loop infinitely. - The cluster chain includes a loop. - There is no UNUSED entry in the cluster chain. (2) Condition for exfat_create_upcase_table() to loop infinitely. - The cluster chain of the root directory includes a loop. - There are no UNUSED entry and up-case table entry in the cluster chain of the root directory. (3) Condition for exfat_load_bitmap() to loop infinitely. - The cluster chain of the root directory includes a loop. - There are no UNUSED entry and bitmap entry in the cluster chain of the root directory. (4) Condition for exfat_find_dir_entry() to loop infinitely. - The cluster chain includes a loop. - The unused directory entries were exhausted by some operation. (5) Condition for exfat_check_dir_empty() to loop infinitely. - The cluster chain includes a loop. - The unused directory entries were exhausted by some operation. - All files and sub-directories under the directory are deleted. This commit adds checks to break the above infinite loop. Signed-off-by: Yuezhang Mo <Yuezhang.Mo(a)sony.com> Signed-off-by: Namjae Jeon <linkinjeon(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- LLM Generated explanations, may be completely bogus: **YES** This commit should be backported to stable kernel trees for the following critical reasons: ## Security Impact - Prevents Multiple Infinite Loop Vulnerabilities The commit fixes **five distinct infinite loop conditions** that can occur due to filesystem corruption, each representing a potential denial-of-service vulnerability: 1. **exfat_count_dir_entries()** - Adds loop detection using `sbi->used_clusters` as a bound 2. **exfat_create_upcase_table()** - Addressed through root directory chain validation 3. **exfat_load_bitmap()** - Addressed through root directory chain validation 4. **exfat_find_dir_entry()** - Adds loop detection using `EXFAT_DATA_CLUSTER_COUNT(sbi)` 5. **exfat_check_dir_empty()** - Adds loop detection using `EXFAT_DATA_CLUSTER_COUNT(sbi)` ## Critical Bug Fix Characteristics 1. **Fixes Real Security Issues**: The infinite loops can cause system hangs and DoS conditions when mounting corrupted/malicious exFAT filesystems 2. **Small, Contained Changes**: The fix adds simple counter checks (4-5 lines per location) without architectural changes 3. **Clear Root Cause**: Addresses missing validation of cluster chain loops in directory traversal 4. **Pattern of Similar Fixes**: This follows three previous infinite loop fixes in the same subsystem (commits b0522303f672, a5324b3a488d, fee873761bd9), all of which fix similar issues dating back to the original exfat implementation ## Code Analysis Shows Low Risk The changes are minimal and safe: - Adds `unsigned int clu_count = 0` declarations - Increments counter when following cluster chains - Breaks traversal if counter exceeds valid cluster count - In `exfat_count_num_clusters()`: adds explicit loop detection with error message ## Follows Stable Kernel Rules ✓ Fixes critical bugs (infinite loops/DoS) ✓ Minimal code changes (~50 lines total) ✓ No new features or API changes ✓ Similar fixes already backported (the three previous infinite loop fixes) ✓ Clear error conditions with proper error returns (-EIO) The commit message explicitly states these are corruption-triggered infinite loops, and the pattern matches previous fixes that have "Fixes:" tags pointing to the original exfat implementation. This is a critical reliability and security fix that prevents system hangs when handling corrupted exFAT filesystems. fs/exfat/dir.c | 12 ++++++++++++ fs/exfat/fatent.c | 10 ++++++++++ fs/exfat/namei.c | 5 +++++ fs/exfat/super.c | 32 +++++++++++++++++++++----------- 4 files changed, 48 insertions(+), 11 deletions(-) diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index 3103b932b674..ee060e26f51d 100644 --- a/fs/exfat/dir.c +++ b/fs/exfat/dir.c @@ -996,6 +996,7 @@ int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei, struct exfat_hint_femp candi_empty; struct exfat_sb_info *sbi = EXFAT_SB(sb); int num_entries = exfat_calc_num_entries(p_uniname); + unsigned int clu_count = 0; if (num_entries < 0) return num_entries; @@ -1133,6 +1134,10 @@ int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei, } else { if (exfat_get_next_cluster(sb, &clu.dir)) return -EIO; + + /* break if the cluster chain includes a loop */ + if (unlikely(++clu_count > EXFAT_DATA_CLUSTER_COUNT(sbi))) + goto not_found; } } @@ -1195,6 +1200,7 @@ int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir) int i, count = 0; int dentries_per_clu; unsigned int entry_type; + unsigned int clu_count = 0; struct exfat_chain clu; struct exfat_dentry *ep; struct exfat_sb_info *sbi = EXFAT_SB(sb); @@ -1227,6 +1233,12 @@ int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir) } else { if (exfat_get_next_cluster(sb, &(clu.dir))) return -EIO; + + if (unlikely(++clu_count > sbi->used_clusters)) { + exfat_fs_error(sb, "FAT or bitmap is corrupted"); + return -EIO; + } + } } diff --git a/fs/exfat/fatent.c b/fs/exfat/fatent.c index 23065f948ae7..232cc7f8ab92 100644 --- a/fs/exfat/fatent.c +++ b/fs/exfat/fatent.c @@ -490,5 +490,15 @@ int exfat_count_num_clusters(struct super_block *sb, } *ret_count = count; + + /* + * since exfat_count_used_clusters() is not called, sbi->used_clusters + * cannot be used here. + */ + if (unlikely(i == sbi->num_clusters && clu != EXFAT_EOF_CLUSTER)) { + exfat_fs_error(sb, "The cluster chain has a loop"); + return -EIO; + } + return 0; } diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c index fede0283d6e2..f5f1c4e8a29f 100644 --- a/fs/exfat/namei.c +++ b/fs/exfat/namei.c @@ -890,6 +890,7 @@ static int exfat_check_dir_empty(struct super_block *sb, { int i, dentries_per_clu; unsigned int type; + unsigned int clu_count = 0; struct exfat_chain clu; struct exfat_dentry *ep; struct exfat_sb_info *sbi = EXFAT_SB(sb); @@ -926,6 +927,10 @@ static int exfat_check_dir_empty(struct super_block *sb, } else { if (exfat_get_next_cluster(sb, &(clu.dir))) return -EIO; + + /* break if the cluster chain includes a loop */ + if (unlikely(++clu_count > EXFAT_DATA_CLUSTER_COUNT(sbi))) + break; } } diff --git a/fs/exfat/super.c b/fs/exfat/super.c index 7ed858937d45..3a9ec75ab452 100644 --- a/fs/exfat/super.c +++ b/fs/exfat/super.c @@ -341,13 +341,12 @@ static void exfat_hash_init(struct super_block *sb) INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); } -static int exfat_read_root(struct inode *inode) +static int exfat_read_root(struct inode *inode, struct exfat_chain *root_clu) { struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct exfat_inode_info *ei = EXFAT_I(inode); - struct exfat_chain cdir; - int num_subdirs, num_clu = 0; + int num_subdirs; exfat_chain_set(&ei->dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); ei->entry = -1; @@ -360,12 +359,9 @@ static int exfat_read_root(struct inode *inode) ei->hint_stat.clu = sbi->root_dir; ei->hint_femp.eidx = EXFAT_HINT_NONE; - exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); - if (exfat_count_num_clusters(sb, &cdir, &num_clu)) - return -EIO; - i_size_write(inode, num_clu << sbi->cluster_size_bits); + i_size_write(inode, EXFAT_CLU_TO_B(root_clu->size, sbi)); - num_subdirs = exfat_count_dir_entries(sb, &cdir); + num_subdirs = exfat_count_dir_entries(sb, root_clu); if (num_subdirs < 0) return -EIO; set_nlink(inode, num_subdirs + EXFAT_MIN_SUBDIR); @@ -578,7 +574,8 @@ static int exfat_verify_boot_region(struct super_block *sb) } /* mount the file system volume */ -static int __exfat_fill_super(struct super_block *sb) +static int __exfat_fill_super(struct super_block *sb, + struct exfat_chain *root_clu) { int ret; struct exfat_sb_info *sbi = EXFAT_SB(sb); @@ -595,6 +592,18 @@ static int __exfat_fill_super(struct super_block *sb) goto free_bh; } + /* + * Call exfat_count_num_cluster() before searching for up-case and + * bitmap directory entries to avoid infinite loop if they are missing + * and the cluster chain includes a loop. + */ + exfat_chain_set(root_clu, sbi->root_dir, 0, ALLOC_FAT_CHAIN); + ret = exfat_count_num_clusters(sb, root_clu, &root_clu->size); + if (ret) { + exfat_err(sb, "failed to count the number of clusters in root"); + goto free_bh; + } + ret = exfat_create_upcase_table(sb); if (ret) { exfat_err(sb, "failed to load upcase table"); @@ -627,6 +636,7 @@ static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) struct exfat_sb_info *sbi = sb->s_fs_info; struct exfat_mount_options *opts = &sbi->options; struct inode *root_inode; + struct exfat_chain root_clu; int err; if (opts->allow_utime == (unsigned short)-1) @@ -645,7 +655,7 @@ static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS; - err = __exfat_fill_super(sb); + err = __exfat_fill_super(sb, &root_clu); if (err) { exfat_err(sb, "failed to recognize exfat type"); goto check_nls_io; @@ -680,7 +690,7 @@ static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) root_inode->i_ino = EXFAT_ROOT_INO; inode_set_iversion(root_inode, 1); - err = exfat_read_root(root_inode); + err = exfat_read_root(root_inode, &root_clu); if (err) { exfat_err(sb, "failed to initialize root inode"); goto put_inode; -- 2.39.5

2 months, 3 weeks

1
4
0 0

[PATCH 6.12 v2] ice/ptp: fix crosstimestamp reporting

by Markus Blöchl

From: Anton Nadezhdin <anton.nadezhdin(a)intel.com> commit a5a441ae283d54ec329aadc7426991dc32786d52 upstream. Set use_nsecs=true as timestamp is reported in ns. Lack of this result in smaller timestamp error window which cause error during phc2sys execution on E825 NICs: phc2sys[1768.256]: ioctl PTP_SYS_OFFSET_PRECISE: Invalid argument This problem was introduced in the cited commit which omitted setting use_nsecs to true when converting the ice driver to use convert_base_to_cs(). Testing hints (ethX is PF netdev): phc2sys -s ethX -c CLOCK_REALTIME -O 37 -m phc2sys[1769.256]: CLOCK_REALTIME phc offset -5 s0 freq -0 delay 0 Fixes: d4bea547ebb57 ("ice/ptp: Remove convert_art_to_tsc()") Signed-off-by: Anton Nadezhdin <anton.nadezhdin(a)intel.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov(a)intel.com> Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski(a)intel.com> Tested-by: Rinitha S <sx.rinitha(a)intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen(a)intel.com> Signed-off-by: Markus Blöchl <markus(a)blochl.de> --- Hi Greg, please consider this backport for linux-6.12.y It fixes a regression from the series around d4bea547ebb57 ("ice/ptp: Remove convert_art_to_tsc()") which affected multiple drivers and occasionally caused phc2sys to fail on ioctl(fd, PTP_SYS_OFFSET_PRECISE, ...). This was the initial fix for ice but apparently tagging it for stable was forgotten during submission. The hunk was moved around slightly in the upstream commit 92456e795ac6 ("ice: Add unified ice_capture_crosststamp") from ice_ptp_get_syncdevicetime() into another helper function ice_capture_crosststamp() so its indentation and context have changed. I adapted it to apply cleanly. --- Changes in v2: - Expand reference to upstream commit to full 40 character SHA - Add branch 6.12 target designator to PATCH prefix - Rebase onto current 6.12.41 - Link to v1: https://lore.kernel.org/r/20250725-ice_crosstimestamp_reporting-v1-1-3d0473… --- drivers/net/ethernet/intel/ice/ice_ptp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c index 7c6f81beaee4602050b4cf366441a2584507d949..369c968a0117d0f7012241fd3e2c0a45a059bfa4 100644 --- a/drivers/net/ethernet/intel/ice/ice_ptp.c +++ b/drivers/net/ethernet/intel/ice/ice_ptp.c @@ -2226,6 +2226,7 @@ ice_ptp_get_syncdevicetime(ktime_t *device, hh_ts = ((u64)hh_ts_hi << 32) | hh_ts_lo; system->cycles = hh_ts; system->cs_id = CSID_X86_ART; + system->use_nsecs = true; /* Read Device source clock time */ hh_ts_lo = rd32(hw, GLTSYN_HHTIME_L(tmr_idx)); hh_ts_hi = rd32(hw, GLTSYN_HHTIME_H(tmr_idx)); --- base-commit: 8f5ff9784f3262e6e85c68d86f8b7931827f2983 change-id: 20250716-ice_crosstimestamp_reporting-b6236a246c48 Best regards, -- Markus Blöchl <markus(a)blochl.de> --

2 months, 3 weeks

2
1
0 0

[PATCH] mm/userfaultfd: fix missing PTE unmap for non-migration entries

by Sasha Levin

When handling non-swap entries in move_pages_pte(), the error handling for entries that are NOT migration entries fails to unmap the page table entries before jumping to the error handling label. This results in a kmap/kunmap imbalance which on CONFIG_HIGHPTE systems triggers a WARNING in kunmap_local_indexed() because the kmap stack is corrupted. Example call trace on ARM32 (CONFIG_HIGHPTE enabled): WARNING: CPU: 1 PID: 633 at mm/highmem.c:622 kunmap_local_indexed+0x178/0x17c Call trace: kunmap_local_indexed from move_pages+0x964/0x19f4 move_pages from userfaultfd_ioctl+0x129c/0x2144 userfaultfd_ioctl from sys_ioctl+0x558/0xd24 The issue was introduced with the UFFDIO_MOVE feature but became more frequent with the addition of guard pages (commit 7c53dfbdb024 ("mm: add PTE_MARKER_GUARD PTE marker")) which made the non-migration entry code path more commonly executed during userfaultfd operations. Fix this by ensuring PTEs are properly unmapped in all non-swap entry paths before jumping to the error handling label, not just for migration entries. Fixes: adef440691ba ("userfaultfd: UFFDIO_MOVE uABI") Cc: stable(a)vger.kernel.org Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- mm/userfaultfd.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 8253978ee0fb1..7c298e9cbc18f 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -1384,14 +1384,15 @@ static int move_pages_pte(struct mm_struct *mm, pmd_t *dst_pmd, pmd_t *src_pmd, entry = pte_to_swp_entry(orig_src_pte); if (non_swap_entry(entry)) { + pte_unmap(src_pte); + pte_unmap(dst_pte); + src_pte = dst_pte = NULL; if (is_migration_entry(entry)) { - pte_unmap(src_pte); - pte_unmap(dst_pte); - src_pte = dst_pte = NULL; migration_entry_wait(mm, src_pmd, src_addr); err = -EAGAIN; - } else + } else { err = -EFAULT; + } goto out; } -- 2.39.5

2 months, 3 weeks

5
22
0 0

[PATCH v5 1/1] userfaultfd: fix a crash in UFFDIO_MOVE when PMD is a migration entry

by Suren Baghdasaryan

When UFFDIO_MOVE encounters a migration PMD entry, it proceeds with obtaining a folio and accessing it even though the entry is swp_entry_t. Add the missing check and let split_huge_pmd() handle migration entries. While at it also remove unnecessary folio check. Fixes: adef440691ba ("userfaultfd: UFFDIO_MOVE uABI") Reported-by: syzbot+b446dbe27035ef6bd6c2(a)syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/68794b5c.a70a0220.693ce.0050.GAE@google.com/ Signed-off-by: Suren Baghdasaryan <surenb(a)google.com> Reviewed-by: Peter Xu <peterx(a)redhat.com> Cc: stable(a)vger.kernel.org --- Applies to mm-unstable after reverting older v4 [1] version. Changes since v4 [1] - Removed extra folio check, per David Hildenbrand [1] https://lore.kernel.org/all/20250806220022.926763-1-surenb@google.com/ mm/userfaultfd.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 5431c9dd7fd7..aefdf3a812a1 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -1826,13 +1826,16 @@ ssize_t move_pages(struct userfaultfd_ctx *ctx, unsigned long dst_start, /* Check if we can move the pmd without splitting it. */ if (move_splits_huge_pmd(dst_addr, src_addr, src_start + len) || !pmd_none(dst_pmdval)) { - struct folio *folio = pmd_folio(*src_pmd); - - if (!folio || (!is_huge_zero_folio(folio) && - !PageAnonExclusive(&folio->page))) { - spin_unlock(ptl); - err = -EBUSY; - break; + /* Can be a migration entry */ + if (pmd_present(*src_pmd)) { + struct folio *folio = pmd_folio(*src_pmd); + + if (!is_huge_zero_folio(folio) && + !PageAnonExclusive(&folio->page)) { + spin_unlock(ptl); + err = -EBUSY; + break; + } } spin_unlock(ptl); -- 2.50.1.703.g449372360f-goog

2 months, 3 weeks

2
1
0 0

[PATCH] accel/ivpu: Fix potential Spectre issue in debugfs

by Jacek Lawrynowicz

Fix potential Spectre vulnerability in repoted by smatch: warn: potential spectre issue 'vdev->hw->hws.grace_period' [w] (local cap) warn: potential spectre issue 'vdev->hw->hws.process_grace_period' [w] (local cap) warn: potential spectre issue 'vdev->hw->hws.process_quantum' [w] (local cap) The priority_bands_fops_write() function in ivpu_debugfs.c uses an index 'band' derived from user input. This index is used to write to the vdev->hw->hws.grace_period, vdev->hw->hws.process_grace_period, and vdev->hw->hws.process_quantum arrays. This pattern presented a potential Spectre Variant 1 (Bounds Check Bypass) vulnerability. An attacker-controlled 'band' value could theoretically lead to speculative out-of-bounds array writes if the CPU speculatively executed these assignments before the bounds check on 'band' was fully resolved. This commit mitigates this potential vulnerability by sanitizing the 'band' index using array_index_nospec() before it is used in the array assignments. The array_index_nospec() function ensures that 'band' is constrained to the valid range [0, VPU_JOB_SCHEDULING_PRIORITY_BAND_COUNT - 1], even during speculative execution. Fixes: 320323d2e545 ("accel/ivpu: Add debugfs interface for setting HWS priority bands") Cc: <stable(a)vger.kernel.org> # v6.15+ Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz(a)linux.intel.com> --- drivers/accel/ivpu/ivpu_debugfs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/accel/ivpu/ivpu_debugfs.c b/drivers/accel/ivpu/ivpu_debugfs.c index cd24ccd20ba6c..2ffe5bf8f1fab 100644 --- a/drivers/accel/ivpu/ivpu_debugfs.c +++ b/drivers/accel/ivpu/ivpu_debugfs.c @@ -5,6 +5,7 @@ #include <linux/debugfs.h> #include <linux/fault-inject.h> +#include <linux/nospec.h> #include <drm/drm_debugfs.h> #include <drm/drm_file.h> @@ -464,6 +465,7 @@ priority_bands_fops_write(struct file *file, const char __user *user_buf, size_t if (band >= VPU_JOB_SCHEDULING_PRIORITY_BAND_COUNT) return -EINVAL; + band = array_index_nospec(band, VPU_JOB_SCHEDULING_PRIORITY_BAND_COUNT); vdev->hw->hws.grace_period[band] = grace_period; vdev->hw->hws.process_grace_period[band] = process_grace_period; vdev->hw->hws.process_quantum[band] = process_quantum; -- 2.45.1

2 months, 3 weeks

2
1
0 0

[PATCH v2] NFSD: Fix destination buffer size in nfsd4_ssc_setup_dul()

by Thorsten Blum

Commit 5304877936c0 ("NFSD: Fix strncpy() fortify warning") replaced strncpy(,, sizeof(..)) with strlcpy(,, sizeof(..) - 1), but strlcpy() already guaranteed NUL-termination of the destination buffer and subtracting one byte potentially truncated the source string. The incorrect size was then carried over in commit 72f78ae00a8e ("NFSD: move from strlcpy with unused retval to strscpy") when switching from strlcpy() to strscpy(). Fix this off-by-one error by using the full size of the destination buffer again. Cc: stable(a)vger.kernel.org Fixes: 5304877936c0 ("NFSD: Fix strncpy() fortify warning") Signed-off-by: Thorsten Blum <thorsten.blum(a)linux.dev> --- Changes in v2: - Use three parameter variant of strscpy() for easier backporting - Link to v1: https://lore.kernel.org/lkml/20250805175302.29386-2-thorsten.blum@linux.dev/ --- fs/nfsd/nfs4proc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 71b428efcbb5..954543e92988 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1469,7 +1469,7 @@ static __be32 nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr, return 0; } if (work) { - strscpy(work->nsui_ipaddr, ipaddr, sizeof(work->nsui_ipaddr) - 1); + strscpy(work->nsui_ipaddr, ipaddr, sizeof(work->nsui_ipaddr)); refcount_set(&work->nsui_refcnt, 2); work->nsui_busy = true; list_add_tail(&work->nsui_list, &nn->nfsd_ssc_mount_list); -- 2.50.1

2 months, 3 weeks

2
1
0 0

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