Linux-stable-mirror

linux-stable-mirror@lists.linaro.org

8 participants
123732 discussions

Re: [PATCH] dma-mapping: fix direction in dma_alloc direction traces

by Petr Tesarik

Cc: stable(a)vger.kernel.org (One day, I'll finally remember, I promise.) Petr T On Wed, 1 Oct 2025 08:10:28 +0200 Petr Tesarik <ptesarik(a)suse.com> wrote: > Set __entry->dir to the actual "dir" parameter of all trace events > in dma_alloc_class. This struct member was left uninitialized by > mistake. > > Signed-off-by: Petr Tesarik <ptesarik(a)suse.com> > Fixes: 3afff779a725 ("dma-mapping: trace dma_alloc/free direction") > --- > include/trace/events/dma.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/include/trace/events/dma.h b/include/trace/events/dma.h > index d8ddc27b6a7c8..945fcbaae77e9 100644 > --- a/include/trace/events/dma.h > +++ b/include/trace/events/dma.h > @@ -134,6 +134,7 @@ DECLARE_EVENT_CLASS(dma_alloc_class, > __entry->dma_addr = dma_addr; > __entry->size = size; > __entry->flags = flags; > + __entry->dir = dir; > __entry->attrs = attrs; > ), >

3 months

[PATCH v3] fbdev/simplefb: Fix use after free in simplefb_detach_genpds()

by Janne Grunau

The pm_domain cleanup can not be devres managed as it uses struct simplefb_par which is allocated within struct fb_info by framebuffer_alloc(). This allocation is explicitly freed by unregister_framebuffer() in simplefb_remove(). Devres managed cleanup runs after the device remove call and thus can no longer access struct simplefb_par. Call simplefb_detach_genpds() explicitly from simplefb_destroy() like the cleanup functions for clocks and regulators. Fixes an use after free on M2 Mac mini during aperture_remove_conflicting_devices() using the downstream asahi kernel with Debian's kernel config. For unknown reasons this started to consistently dereference an invalid pointer in v6.16.3 based kernels. [ 6.736134] BUG: KASAN: slab-use-after-free in simplefb_detach_genpds+0x58/0x220 [ 6.743545] Read of size 4 at addr ffff8000304743f0 by task (udev-worker)/227 [ 6.750697] [ 6.752182] CPU: 6 UID: 0 PID: 227 Comm: (udev-worker) Tainted: G S 6.16.3-asahi+ #16 PREEMPTLAZY [ 6.752186] Tainted: [S]=CPU_OUT_OF_SPEC [ 6.752187] Hardware name: Apple Mac mini (M2, 2023) (DT) [ 6.752189] Call trace: [ 6.752190] show_stack+0x34/0x98 (C) [ 6.752194] dump_stack_lvl+0x60/0x80 [ 6.752197] print_report+0x17c/0x4d8 [ 6.752201] kasan_report+0xb4/0x100 [ 6.752206] __asan_report_load4_noabort+0x20/0x30 [ 6.752209] simplefb_detach_genpds+0x58/0x220 [ 6.752213] devm_action_release+0x50/0x98 [ 6.752216] release_nodes+0xd0/0x2c8 [ 6.752219] devres_release_all+0xfc/0x178 [ 6.752221] device_unbind_cleanup+0x28/0x168 [ 6.752224] device_release_driver_internal+0x34c/0x470 [ 6.752228] device_release_driver+0x20/0x38 [ 6.752231] bus_remove_device+0x1b0/0x380 [ 6.752234] device_del+0x314/0x820 [ 6.752238] platform_device_del+0x3c/0x1e8 [ 6.752242] platform_device_unregister+0x20/0x50 [ 6.752246] aperture_detach_platform_device+0x1c/0x30 [ 6.752250] aperture_detach_devices+0x16c/0x290 [ 6.752253] aperture_remove_conflicting_devices+0x34/0x50 ... [ 6.752343] [ 6.967409] Allocated by task 62: [ 6.970724] kasan_save_stack+0x3c/0x70 [ 6.974560] kasan_save_track+0x20/0x40 [ 6.978397] kasan_save_alloc_info+0x40/0x58 [ 6.982670] __kasan_kmalloc+0xd4/0xd8 [ 6.986420] __kmalloc_noprof+0x194/0x540 [ 6.990432] framebuffer_alloc+0xc8/0x130 [ 6.994444] simplefb_probe+0x258/0x2378 ... [ 7.054356] [ 7.055838] Freed by task 227: [ 7.058891] kasan_save_stack+0x3c/0x70 [ 7.062727] kasan_save_track+0x20/0x40 [ 7.066565] kasan_save_free_info+0x4c/0x80 [ 7.070751] __kasan_slab_free+0x6c/0xa0 [ 7.074675] kfree+0x10c/0x380 [ 7.077727] framebuffer_release+0x5c/0x90 [ 7.081826] simplefb_destroy+0x1b4/0x2c0 [ 7.085837] put_fb_info+0x98/0x100 [ 7.089326] unregister_framebuffer+0x178/0x320 [ 7.093861] simplefb_remove+0x3c/0x60 [ 7.097611] platform_remove+0x60/0x98 [ 7.101361] device_remove+0xb8/0x160 [ 7.105024] device_release_driver_internal+0x2fc/0x470 [ 7.110256] device_release_driver+0x20/0x38 [ 7.114529] bus_remove_device+0x1b0/0x380 [ 7.118628] device_del+0x314/0x820 [ 7.122116] platform_device_del+0x3c/0x1e8 [ 7.126302] platform_device_unregister+0x20/0x50 [ 7.131012] aperture_detach_platform_device+0x1c/0x30 [ 7.136157] aperture_detach_devices+0x16c/0x290 [ 7.140779] aperture_remove_conflicting_devices+0x34/0x50 ... Reported-by: Daniel Huhardeaux <tech(a)tootai.net> Cc: stable(a)vger.kernel.org Fixes: 92a511a568e44 ("fbdev/simplefb: Add support for generic power-domains") Signed-off-by: Janne Grunau <j(a)jannau.net> --- Changes in v3: - release power-domains on probe errors - set par->num_genpds when it's <= 1 - set par->num_genpds to 0 after detaching - Link to v2: https://lore.kernel.org/r/20250908-simplefb-genpd-uaf-v2-1-f88a0d9d880f@jan… Changes in v2: - reworked change due to missed use of `par->num_genpds` before setting it. Missed in testing due to mixing up FB_SIMPLE and SYSFB_SIMPLEFB. - Link to v1: https://lore.kernel.org/r/20250901-simplefb-genpd-uaf-v1-1-0d9f3a34c4dc@jan… --- drivers/video/fbdev/simplefb.c | 31 +++++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-) diff --git a/drivers/video/fbdev/simplefb.c b/drivers/video/fbdev/simplefb.c index 1893815dc67f4c1403eea42c0e10a7ead4d96ba9..6acf5a00c2bacfab89c3a63bab3d8b1b091a20a8 100644 --- a/drivers/video/fbdev/simplefb.c +++ b/drivers/video/fbdev/simplefb.c @@ -93,6 +93,7 @@ struct simplefb_par { static void simplefb_clocks_destroy(struct simplefb_par *par); static void simplefb_regulators_destroy(struct simplefb_par *par); +static void simplefb_detach_genpds(void *res); /* * fb_ops.fb_destroy is called by the last put_fb_info() call at the end @@ -105,6 +106,7 @@ static void simplefb_destroy(struct fb_info *info) simplefb_regulators_destroy(info->par); simplefb_clocks_destroy(info->par); + simplefb_detach_genpds(info->par); if (info->screen_base) iounmap(info->screen_base); @@ -445,13 +447,14 @@ static void simplefb_detach_genpds(void *res) if (!IS_ERR_OR_NULL(par->genpds[i])) dev_pm_domain_detach(par->genpds[i], true); } + par->num_genpds = 0; } static int simplefb_attach_genpds(struct simplefb_par *par, struct platform_device *pdev) { struct device *dev = &pdev->dev; - unsigned int i; + unsigned int i, num_genpds; int err; err = of_count_phandle_with_args(dev->of_node, "power-domains", @@ -465,26 +468,35 @@ static int simplefb_attach_genpds(struct simplefb_par *par, return err; } - par->num_genpds = err; + num_genpds = err; /* * Single power-domain devices are handled by the driver core, so * nothing to do here. */ - if (par->num_genpds <= 1) + if (num_genpds <= 1) { + par->num_genpds = num_genpds; return 0; + } - par->genpds = devm_kcalloc(dev, par->num_genpds, sizeof(*par->genpds), + par->genpds = devm_kcalloc(dev, num_genpds, sizeof(*par->genpds), GFP_KERNEL); if (!par->genpds) return -ENOMEM; - par->genpd_links = devm_kcalloc(dev, par->num_genpds, + par->genpd_links = devm_kcalloc(dev, num_genpds, sizeof(*par->genpd_links), GFP_KERNEL); if (!par->genpd_links) return -ENOMEM; + /* + * Set par->num_genpds only after genpds and genpd_links are allocated + * to exit early from simplefb_detach_genpds() without full + * initialisation. + */ + par->num_genpds = num_genpds; + for (i = 0; i < par->num_genpds; i++) { par->genpds[i] = dev_pm_domain_attach_by_id(dev, i); if (IS_ERR(par->genpds[i])) { @@ -506,9 +518,10 @@ static int simplefb_attach_genpds(struct simplefb_par *par, dev_warn(dev, "failed to link power-domain %u\n", i); } - return devm_add_action_or_reset(dev, simplefb_detach_genpds, par); + return 0; } #else +static void simplefb_detach_genpds(void *res) { } static int simplefb_attach_genpds(struct simplefb_par *par, struct platform_device *pdev) { @@ -622,18 +635,20 @@ static int simplefb_probe(struct platform_device *pdev) ret = devm_aperture_acquire_for_platform_device(pdev, par->base, par->size); if (ret) { dev_err(&pdev->dev, "Unable to acquire aperture: %d\n", ret); - goto error_regulators; + goto error_genpds; } ret = register_framebuffer(info); if (ret < 0) { dev_err(&pdev->dev, "Unable to register simplefb: %d\n", ret); - goto error_regulators; + goto error_genpds; } dev_info(&pdev->dev, "fb%d: simplefb registered!\n", info->node); return 0; +error_genpds: + simplefb_detach_genpds(par); error_regulators: simplefb_regulators_destroy(par); error_clocks: --- base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585 change-id: 20250901-simplefb-genpd-uaf-352704761a29 Best regards, -- Janne Grunau <j(a)jannau.net>

3 months

Check this out at Amazon

by llk16 9157

Purchase this ALCHIMERA ebook, and a portion of the proceeds will help children and families in need in Gaza, Ukraine, and the DRC: Your gesture is a seed of love that will bear eternal fruit. https://a.co/d/aDuLWHN 🆘Buy this book, save a life today. Every word you read, every page you turn, becomes an act of compassion. 💔 Children cry from hunger in Gaza, Ukraine, and eastern DRC. Your purchase becomes a hot meal, a blanket, a breath of hope for those who have nothing left. This isn't just an ebook. It's a mission. A portion of the funds is sent to disaster-stricken families suffering from serious hunger. 🙏 Share this message. Give this book as a gift. Increase the number of lifesaving actions. Every share is an answered prayer. Every purchase is a helping hand. May God bless you abundantly for your generous heart. This book is in your hands. Someone's life too.

3 months

[PATCH] ext4: fix use-after-free in extent header access

by Deepanshu Kartikey

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master syzbot reported use-after-free bugs when accessing extent headers in ext4_ext_insert_extent() and ext4_ext_correct_indexes(). These occur when the extent path structure becomes invalid during operations. The crashes show two patterns: 1. In ext4_ext_map_blocks(), the extent header can be corrupted after ext4_find_extent() returns, particularly during concurrent writes to the same file. 2. In ext4_ext_correct_indexes(), accessing path[depth] causes a use-after-free, indicating the path structure itself is corrupted. This is partially exposed by commit 665575cff098 ("filemap: move prefaulting out of hot write path") which changed timing windows in the write path, making these races more likely to occur. Fix this by adding validation checks: - In ext4_ext_map_blocks(): validate the extent header after getting the path from ext4_find_extent() - In ext4_ext_correct_indexes(): validate the path pointer before dereferencing and check extent header magic While these checks are defensive and don't address the root cause of path corruption, they prevent kernel crashes from invalid memory access. A more comprehensive fix to path lifetime management may be needed in the future. Reported-by: syzbot+9db318d6167044609878(a)syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=9db318d6167044609878 Fixes: 665575cff098 ("filemap: move prefaulting out of hot write path") Cc: stable(a)vger.kernel.org Signed-off-by: Deepanshu Kartikey <kartikey406(a)gmail.com> --- fs/ext4/extents.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index ca5499e9412b..903578d5f68d 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -1708,7 +1708,9 @@ static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode, struct ext4_extent *ex; __le32 border; int k, err = 0; - + if (!path || depth < 0 || depth > EXT4_MAX_EXTENT_DEPTH) { + return -EFSCORRUPTED; + } eh = path[depth].p_hdr; ex = path[depth].p_ext; @@ -4200,6 +4202,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, unsigned int allocated_clusters = 0; struct ext4_allocation_request ar; ext4_lblk_t cluster_offset; + struct ext4_extent_header *eh; ext_debug(inode, "blocks %u/%u requested\n", map->m_lblk, map->m_len); trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags); @@ -4212,7 +4215,12 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, } depth = ext_depth(inode); - + eh = path[depth].p_hdr; + if (!eh || le16_to_cpu(eh->eh_magic) != EXT4_EXT_MAGIC) { + EXT4_ERROR_INODE(inode, "invalid extent header after find_extent"); + err = -EFSCORRUPTED; + goto out; + } /* * consistent leaf must not be empty; * this situation is possible, though, _during_ tree modification; -- 2.43.0

3 months

+ mm-damon-vaddr-do-not-repeat-pte_offset_map_lock-until-success.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: mm/damon/vaddr: do not repeat pte_offset_map_lock() until success has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-damon-vaddr-do-not-repeat-pte_offset_map_lock-until-success.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: SeongJae Park <sj(a)kernel.org> Subject: mm/damon/vaddr: do not repeat pte_offset_map_lock() until success Date: Mon, 29 Sep 2025 17:44:09 -0700 DAMON's virtual address space operation set implementation (vaddr) calls pte_offset_map_lock() inside the page table walk callback function. This is for reading and writing page table accessed bits. If pte_offset_map_lock() fails, it retries by returning the page table walk callback function with ACTION_AGAIN. pte_offset_map_lock() can continuously fail if the target is a pmd migration entry, though. Hence it could cause an infinite page table walk if the migration cannot be done until the page table walk is finished. This indeed caused a soft lockup when CPU hotplugging and DAMON were running in parallel. Avoid the infinite loop by simply not retrying the page table walk. DAMON is promising only a best-effort accuracy, so missing access to such pages is no problem. Link: https://lkml.kernel.org/r/20250930004410.55228-1-sj@kernel.org Fixes: 7780d04046a2 ("mm/pagewalkers: ACTION_AGAIN if pte_offset_map_lock() fails") Signed-off-by: SeongJae Park <sj(a)kernel.org> Reported-by: Xinyu Zheng <zhengxinyu6(a)huawei.com> Closes: https://lore.kernel.org/20250918030029.2652607-1-zhengxinyu6@huawei.com Acked-by: Hugh Dickins <hughd(a)google.com> Cc: <stable(a)vger.kernel.org> [6.5+] Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/damon/vaddr.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) --- a/mm/damon/vaddr.c~mm-damon-vaddr-do-not-repeat-pte_offset_map_lock-until-success +++ a/mm/damon/vaddr.c @@ -328,10 +328,8 @@ static int damon_mkold_pmd_entry(pmd_t * } pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); - if (!pte) { - walk->action = ACTION_AGAIN; + if (!pte) return 0; - } if (!pte_present(ptep_get(pte))) goto out; damon_ptep_mkold(pte, walk->vma, addr); @@ -481,10 +479,8 @@ regular_page: #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); - if (!pte) { - walk->action = ACTION_AGAIN; + if (!pte) return 0; - } ptent = ptep_get(pte); if (!pte_present(ptent)) goto out; _ Patches currently in -mm which might be from sj(a)kernel.org are mm-damon-vaddr-do-not-repeat-pte_offset_map_lock-until-success.patch

3 months

+ mm-rmap-fix-soft-dirty-and-uffd-wp-bit-loss-when-remapping-zero-filled-mthp-subpage-to-shared-zeropage.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: mm/rmap: fix soft-dirty and uffd-wp bit loss when remapping zero-filled mTHP subpage to shared zeropage has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-rmap-fix-soft-dirty-and-uffd-wp-bit-loss-when-remapping-zero-filled-mthp-subpage-to-shared-zeropage.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: Lance Yang <lance.yang(a)linux.dev> Subject: mm/rmap: fix soft-dirty and uffd-wp bit loss when remapping zero-filled mTHP subpage to shared zeropage Date: Tue, 30 Sep 2025 16:10:40 +0800 When splitting an mTHP and replacing a zero-filled subpage with the shared zeropage, try_to_map_unused_to_zeropage() currently drops several important PTE bits. For userspace tools like CRIU, which rely on the soft-dirty mechanism for incremental snapshots, losing the soft-dirty bit means modified pages are missed, leading to inconsistent memory state after restore. As pointed out by David, the more critical uffd-wp bit is also dropped. This breaks the userfaultfd write-protection mechanism, causing writes to be silently missed by monitoring applications, which can lead to data corruption. Preserve both the soft-dirty and uffd-wp bits from the old PTE when creating the new zeropage mapping to ensure they are correctly tracked. Link: https://lkml.kernel.org/r/20250930081040.80926-1-lance.yang@linux.dev Fixes: b1f202060afe ("mm: remap unused subpages to shared zeropage when splitting isolated thp") Signed-off-by: Lance Yang <lance.yang(a)linux.dev> Suggested-by: David Hildenbrand <david(a)redhat.com> Suggested-by: Dev Jain <dev.jain(a)arm.com> Acked-by: David Hildenbrand <david(a)redhat.com> Reviewed-by: Dev Jain <dev.jain(a)arm.com> Acked-by: Zi Yan <ziy(a)nvidia.com> Cc: Alistair Popple <apopple(a)nvidia.com> Cc: Baolin Wang <baolin.wang(a)linux.alibaba.com> Cc: Barry Song <baohua(a)kernel.org> Cc: Byungchul Park <byungchul(a)sk.com> Cc: Gregory Price <gourry(a)gourry.net> Cc: "Huang, Ying" <ying.huang(a)linux.alibaba.com> Cc: Jann Horn <jannh(a)google.com> Cc: Joshua Hahn <joshua.hahnjy(a)gmail.com> Cc: Liam Howlett <liam.howlett(a)oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com> Cc: Mariano Pache <npache(a)redhat.com> Cc: Mathew Brost <matthew.brost(a)intel.com> Cc: Peter Xu <peterx(a)redhat.com> Cc: Rakie Kim <rakie.kim(a)sk.com> Cc: Rik van Riel <riel(a)surriel.com> Cc: Ryan Roberts <ryan.roberts(a)arm.com> Cc: Usama Arif <usamaarif642(a)gmail.com> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: Yu Zhao <yuzhao(a)google.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/migrate.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) --- a/mm/migrate.c~mm-rmap-fix-soft-dirty-and-uffd-wp-bit-loss-when-remapping-zero-filled-mthp-subpage-to-shared-zeropage +++ a/mm/migrate.c @@ -297,8 +297,7 @@ bool isolate_folio_to_list(struct folio } static bool try_to_map_unused_to_zeropage(struct page_vma_mapped_walk *pvmw, - struct folio *folio, - unsigned long idx) + struct folio *folio, pte_t old_pte, unsigned long idx) { struct page *page = folio_page(folio, idx); pte_t newpte; @@ -307,7 +306,7 @@ static bool try_to_map_unused_to_zeropag return false; VM_BUG_ON_PAGE(!PageAnon(page), page); VM_BUG_ON_PAGE(!PageLocked(page), page); - VM_BUG_ON_PAGE(pte_present(ptep_get(pvmw->pte)), page); + VM_BUG_ON_PAGE(pte_present(old_pte), page); if (folio_test_mlocked(folio) || (pvmw->vma->vm_flags & VM_LOCKED) || mm_forbids_zeropage(pvmw->vma->vm_mm)) @@ -323,6 +322,12 @@ static bool try_to_map_unused_to_zeropag newpte = pte_mkspecial(pfn_pte(my_zero_pfn(pvmw->address), pvmw->vma->vm_page_prot)); + + if (pte_swp_soft_dirty(old_pte)) + newpte = pte_mksoft_dirty(newpte); + if (pte_swp_uffd_wp(old_pte)) + newpte = pte_mkuffd_wp(newpte); + set_pte_at(pvmw->vma->vm_mm, pvmw->address, pvmw->pte, newpte); dec_mm_counter(pvmw->vma->vm_mm, mm_counter(folio)); @@ -365,13 +370,13 @@ static bool remove_migration_pte(struct continue; } #endif + old_pte = ptep_get(pvmw.pte); if (rmap_walk_arg->map_unused_to_zeropage && - try_to_map_unused_to_zeropage(&pvmw, folio, idx)) + try_to_map_unused_to_zeropage(&pvmw, folio, old_pte, idx)) continue; folio_get(folio); pte = mk_pte(new, READ_ONCE(vma->vm_page_prot)); - old_pte = ptep_get(pvmw.pte); entry = pte_to_swp_entry(old_pte); if (!is_migration_entry_young(entry)) _ Patches currently in -mm which might be from lance.yang(a)linux.dev are hung_task-fix-warnings-caused-by-unaligned-lock-pointers.patch mm-thp-fix-mte-tag-mismatch-when-replacing-zero-filled-subpages.patch mm-rmap-fix-soft-dirty-and-uffd-wp-bit-loss-when-remapping-zero-filled-mthp-subpage-to-shared-zeropage.patch mm-clean-up-is_guard_pte_marker.patch

3 months

[PATCH] ext4: fix use-after-free in extent header access

by Deepanshu Kartikey

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master syzbot reported multiple use-after-free bugs when accessing extent headers in various ext4 functions. These occur because extent headers can be freed by concurrent operations while other threads still hold pointers to them. The issue is triggered by racing threads performing concurrent writes to the same file. After commit 665575cff098 ("filemap: move prefaulting out of hot write path"), the write path no longer prefaults pages in the hot path, creating a wider race window where: 1. Thread A calls ext4_find_extent() and gets a path with extent headers 2. Thread A's write attempt fails, entering the slow path 3. During the gap, Thread B modifies the extent tree, freeing nodes 4. Thread A continues using the now-freed extent headers, causing UAF Fix this by validating the extent header in ext4_find_extent() before returning the path. This ensures all callers receive a valid extent path, fixing the race at a single point rather than adding checks throughout the codebase. This addresses crashes in ext4_ext_insert_extent(), ext4_ext_binsearch(), and potentially other locations that use extent paths. Reported-by: syzbot+9db318d6167044609878(a)syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=9db318d6167044609878 Fixes: 665575cff098 ("filemap: move prefaulting out of hot write path") Cc: stable(a)vger.kernel.org Signed-off-by: Deepanshu Kartikey <kartikey406(a)gmail.com> --- fs/ext4/extents.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index ca5499e9412b..04ceae5b0a34 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4200,6 +4200,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, unsigned int allocated_clusters = 0; struct ext4_allocation_request ar; ext4_lblk_t cluster_offset; + struct ext4_extent_header *eh; ext_debug(inode, "blocks %u/%u requested\n", map->m_lblk, map->m_len); trace_ext4_ext_map_blocks_enter(inode, map->m_lblk, map->m_len, flags); @@ -4212,7 +4213,12 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, } depth = ext_depth(inode); - + eh = path[depth].p_hdr; + if (!eh || le16_to_cpu(eh->eh_magic) != EXT4_EXT_MAGIC) { + EXT4_ERROR_INODE(inode, "invalid extent header after find_extent"); + err = -EFSCORRUPTED; + goto out; + } /* * consistent leaf must not be empty; * this situation is possible, though, _during_ tree modification; -- 2.43.0

3 months

RE: Executive Assistants and HNWI Directory to Enhance Your Marketing and Networking

by Brenda Wilson

Hi , Hope you're doing well. I wanted to check if my previous email reached you. Do you need any additional information regarding my previous email? If so, I can provide it for your review. Regards Brenda Marketing Manager Prospect Tech Connect., Please reply with REMOVE if you don't wish to receive further emails -----Original Message----- From: Brenda Wilson Subject: Executive Assistants and HNWI Directory to Enhance Your Marketing and Networking Hi , Our verified database enables accurate outreach to Executive Assistants and high-net-worth individuals. Executive Assistants (by region): USA : 50,000 contacts Europe : 15,000 contacts Canada : 2,000 contacts Middle East : 2,500 contacts HNWI & Senior Decision-Makers (by region, incl. EAs): USA : 500,000 contacts Europe : 50,000 contacts Canada : 10,000 contacts UAE : 7,500 contacts Titles we cover: Business Owners, Founders, Entrepreneurs, C-Level Executives, VPs, and Executive Assistants. Data fields: Name, Job Title, Company, URL, Email, Revenue and more. This list helps reach gatekeepers and decision-makers who oversee charter service partnerships. Happy to share prices if that helps. Eager to receive your feedback. Regards Brenda Marketing Manager Prospect Tech Connect., Please reply with REMOVE if you don't wish to receive further emails

3 months

regression from 6.12.48 to 6.12.49: usb wlan adaptor stops working: bisected

by Wolfgang Walter

Hello,o after upgrading to 6.12.49 my wlan adapter stops working. It is detected: kernel: mt76x2u 4-2:1.0: ASIC revision: 76120044 kernel: mt76x2u 4-2:1.0: ROM patch build: 20141115060606a kernel: usb 3-4: reset high-speed USB device number 2 using xhci_hcd kernel: mt76x2u 4-2:1.0: Firmware Version: 0.0.00 kernel: mt76x2u 4-2:1.0: Build: 1 kernel: mt76x2u 4-2:1.0: Build Time: 201507311614____ but does nor work. The following 2 messages probably are relevant: kernel: mt76x2u 4-2:1.0: MAC RX failed to stop kernel: mt76x2u 4-2:1.0: MAC RX failed to stop later I see a lot of kernel: mt76x2u 4-2:1.0: error: mt76x02u_mcu_wait_resp failed with -110 I bisected it down to commit 9b28ef1e4cc07cdb35da257aa4358d0127168b68 usb: xhci: remove option to change a default ring's TRB cycle bit 9b28ef1e4cc07cdb35da257aa4358d0127168b68 is the first bad commit commit 9b28ef1e4cc07cdb35da257aa4358d0127168b68 Author: Niklas Neronin <niklas.neronin(a)linux.intel.com> Date: Wed Sep 17 08:39:07 2025 -0400 usb: xhci: remove option to change a default ring's TRB cycle bit [ Upstream commit e1b0fa863907a61e86acc19ce2d0633941907c8e ] The TRB cycle bit indicates TRB ownership by the Host Controller (HC) or Host Controller Driver (HCD). New rings are initialized with 'cycle_state' equal to one, and all its TRBs' cycle bits are set to zero. When handling ring expansion, set the source ring cycle bits to the same value as the destination ring. Move the cycle bit setting from xhci_segment_alloc() to xhci_link_rings(), and remove the 'cycle_state' argument from xhci_initialize_ring_info(). The xhci_segment_alloc() function uses kzalloc_node() to allocate segments, ensuring that all TRB cycle bits are initialized to zero. Signed-off-by: Niklas Neronin <niklas.neronin(a)linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman(a)linux.intel.com> Link: https://lore.kernel.org/r/20241106101459.775897-12-mathias.nyman@linux.inte… Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Stable-dep-of: a5c98e8b1398 ("xhci: dbc: Fix full DbC transfer ring after several reconnects") Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Regards, -- Wolfgang Walter Studierendenwerk München Oberbayern Anstalt des öffentlichen Rechts

3 months

[PATCH 6.1] arch_topology: Build cacheinfo from primary CPU

by Wen Yang

From: Pierre Gondois <pierre.gondois(a)arm.com> commit 5944ce092b97caed5d86d961e963b883b5c44ee2 upstream. commit 3fcbf1c77d08 ("arch_topology: Fix cache attributes detection in the CPU hotplug path") adds a call to detect_cache_attributes() to populate the cacheinfo before updating the siblings mask. detect_cache_attributes() allocates memory and can take the PPTT mutex (on ACPI platforms). On PREEMPT_RT kernels, on secondary CPUs, this triggers a: 'BUG: sleeping function called from invalid context' [1] as the code is executed with preemption and interrupts disabled. The primary CPU was previously storing the cache information using the now removed (struct cpu_topology).llc_id: commit 5b8dc787ce4a ("arch_topology: Drop LLC identifier stash from the CPU topology") allocate_cache_info() tries to build the cacheinfo from the primary CPU prior secondary CPUs boot, if the DT/ACPI description contains cache information. If allocate_cache_info() fails, then fallback to the current state for the cacheinfo allocation. [1] will be triggered in such case. When unplugging a CPU, the cacheinfo memory cannot be freed. If it was, then the memory would be allocated early by the re-plugged CPU and would trigger [1]. Note that populate_cache_leaves() might be called multiple times due to populate_leaves being moved up. This is required since detect_cache_attributes() might be called with per_cpu_cacheinfo(cpu) being allocated but not populated. [1]: | BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 | in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0, name: swapper/111 | preempt_count: 1, expected: 0 | RCU nest depth: 1, expected: 1 | 3 locks held by swapper/111/0: | #0: (&pcp->lock){+.+.}-{3:3}, at: get_page_from_freelist+0x218/0x12c8 | #1: (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x48/0xf0 | #2: (&zone->lock){+.+.}-{3:3}, at: rmqueue_bulk+0x64/0xa80 | irq event stamp: 0 | hardirqs last enabled at (0): 0x0 | hardirqs last disabled at (0): copy_process+0x5dc/0x1ab8 | softirqs last enabled at (0): copy_process+0x5dc/0x1ab8 | softirqs last disabled at (0): 0x0 | Preemption disabled at: | migrate_enable+0x30/0x130 | CPU: 111 PID: 0 Comm: swapper/111 Tainted: G W 6.0.0-rc4-rt6-[...] | Call trace: | __kmalloc+0xbc/0x1e8 | detect_cache_attributes+0x2d4/0x5f0 | update_siblings_masks+0x30/0x368 | store_cpu_topology+0x78/0xb8 | secondary_start_kernel+0xd0/0x198 | __secondary_switched+0xb0/0xb4 Signed-off-by: Pierre Gondois <pierre.gondois(a)arm.com> Reviewed-by: Sudeep Holla <sudeep.holla(a)arm.com> Acked-by: Palmer Dabbelt <palmer(a)rivosinc.com> Link: https://lore.kernel.org/r/20230104183033.755668-7-pierre.gondois@arm.com Signed-off-by: Sudeep Holla <sudeep.holla(a)arm.com> Cc: <stable(a)vger.kernel.org> # 6.1.x: c3719bd:cacheinfo: Use RISC-V's init_cache_level() as generic OF implementation Cc: <stable(a)vger.kernel.org> # 6.1.x: 8844c3d:cacheinfo: Return error code in init_of_cache_level( Cc: <stable(a)vger.kernel.org> # 6.1.x: de0df44:cacheinfo: Check 'cache-unified' property to count cache leaves Cc: <stable(a)vger.kernel.org> # 6.1.x: fa4d566:ACPI: PPTT: Remove acpi_find_cache_levels() Cc: <stable(a)vger.kernel.org> # 6.1.x: bd50036:ACPI: PPTT: Update acpi_find_last_cache_level() to acpi_get_cache_info( Cc: <stable(a)vger.kernel.org> # 6.1.x Signed-off-by: Wen Yang <wen.yang(a)linux.dev> --- arch/riscv/kernel/cacheinfo.c | 5 --- drivers/base/arch_topology.c | 12 +++++- drivers/base/cacheinfo.c | 71 ++++++++++++++++++++++++++--------- include/linux/cacheinfo.h | 1 + 4 files changed, 65 insertions(+), 24 deletions(-) diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c index 440a3df5944c..3a13113f1b29 100644 --- a/arch/riscv/kernel/cacheinfo.c +++ b/arch/riscv/kernel/cacheinfo.c @@ -113,11 +113,6 @@ static void fill_cacheinfo(struct cacheinfo **this_leaf, } } -int init_cache_level(unsigned int cpu) -{ - return init_of_cache_level(cpu); -} - int populate_cache_leaves(unsigned int cpu) { struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index e7d6e6657ffa..b1c1dd38ab01 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -736,7 +736,7 @@ void update_siblings_masks(unsigned int cpuid) ret = detect_cache_attributes(cpuid); if (ret && ret != -ENOENT) - pr_info("Early cacheinfo failed, ret = %d\n", ret); + pr_info("Early cacheinfo allocation failed, ret = %d\n", ret); /* update core and thread sibling masks */ for_each_online_cpu(cpu) { @@ -825,7 +825,7 @@ __weak int __init parse_acpi_topology(void) #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV) void __init init_cpu_topology(void) { - int ret; + int cpu, ret; reset_cpu_topology(); ret = parse_acpi_topology(); @@ -840,6 +840,14 @@ void __init init_cpu_topology(void) reset_cpu_topology(); return; } + + for_each_possible_cpu(cpu) { + ret = fetch_cache_info(cpu); + if (ret) { + pr_err("Early cacheinfo failed, ret = %d\n", ret); + break; + } + } } void store_cpu_topology(unsigned int cpuid) diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index ab99b0f0d010..cd943d06d074 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -412,10 +412,6 @@ static void free_cache_attributes(unsigned int cpu) return; cache_shared_cpu_map_remove(cpu); - - kfree(per_cpu_cacheinfo(cpu)); - per_cpu_cacheinfo(cpu) = NULL; - cache_leaves(cpu) = 0; } int __weak init_cache_level(unsigned int cpu) @@ -428,29 +424,71 @@ int __weak populate_cache_leaves(unsigned int cpu) return -ENOENT; } +static inline +int allocate_cache_info(int cpu) +{ + per_cpu_cacheinfo(cpu) = kcalloc(cache_leaves(cpu), + sizeof(struct cacheinfo), GFP_ATOMIC); + if (!per_cpu_cacheinfo(cpu)) { + cache_leaves(cpu) = 0; + return -ENOMEM; + } + + return 0; +} + +int fetch_cache_info(unsigned int cpu) +{ + struct cpu_cacheinfo *this_cpu_ci; + unsigned int levels, split_levels; + int ret; + + if (acpi_disabled) { + ret = init_of_cache_level(cpu); + if (ret < 0) + return ret; + } else { + ret = acpi_get_cache_info(cpu, &levels, &split_levels); + if (ret < 0) + return ret; + + this_cpu_ci = get_cpu_cacheinfo(cpu); + this_cpu_ci->num_levels = levels; + /* + * This assumes that: + * - there cannot be any split caches (data/instruction) + * above a unified cache + * - data/instruction caches come by pair + */ + this_cpu_ci->num_leaves = levels + split_levels; + } + if (!cache_leaves(cpu)) + return -ENOENT; + + return allocate_cache_info(cpu); +} + int detect_cache_attributes(unsigned int cpu) { int ret; - /* Since early detection of the cacheinfo is allowed via this - * function and this also gets called as CPU hotplug callbacks via - * cacheinfo_cpu_online, the initialisation can be skipped and only - * CPU maps can be updated as the CPU online status would be update - * if called via cacheinfo_cpu_online path. + /* Since early initialization/allocation of the cacheinfo is allowed + * via fetch_cache_info() and this also gets called as CPU hotplug + * callbacks via cacheinfo_cpu_online, the init/alloc can be skipped + * as it will happen only once (the cacheinfo memory is never freed). + * Just populate the cacheinfo. */ if (per_cpu_cacheinfo(cpu)) - goto update_cpu_map; + goto populate_leaves; if (init_cache_level(cpu) || !cache_leaves(cpu)) return -ENOENT; - per_cpu_cacheinfo(cpu) = kcalloc(cache_leaves(cpu), - sizeof(struct cacheinfo), GFP_ATOMIC); - if (per_cpu_cacheinfo(cpu) == NULL) { - cache_leaves(cpu) = 0; - return -ENOMEM; - } + ret = allocate_cache_info(cpu); + if (ret) + return ret; +populate_leaves: /* * populate_cache_leaves() may completely setup the cache leaves and * shared_cpu_map or it may leave it partially setup. @@ -459,7 +497,6 @@ int detect_cache_attributes(unsigned int cpu) if (ret) goto free_ci; -update_cpu_map: /* * For systems using DT for cache hierarchy, fw_token * and shared_cpu_map will be set up here only if they are diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h index 00d8e7f9d1c6..dfef57077cd0 100644 --- a/include/linux/cacheinfo.h +++ b/include/linux/cacheinfo.h @@ -85,6 +85,7 @@ int populate_cache_leaves(unsigned int cpu); int cache_setup_acpi(unsigned int cpu); bool last_level_cache_is_valid(unsigned int cpu); bool last_level_cache_is_shared(unsigned int cpu_x, unsigned int cpu_y); +int fetch_cache_info(unsigned int cpu); int detect_cache_attributes(unsigned int cpu); #ifndef CONFIG_ACPI_PPTT /* -- 2.25.1

3 months

Jump to page:

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror