From 619eab23e1ce7c97e54bfc5a417306d94b3f6f13 Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Tue, 21 Apr 2026 11:21:50 +0100 Subject: mm/vma: do not try to unmap a VMA if mmap_prepare() invoked from mmap() The mmap_prepare hook functionality includes the ability to invoke mmap_prepare() from the mmap() hook of existing 'stacked' drivers, that is ones which are capable of calling the mmap hooks of other drivers/file systems (e.g. overlayfs, shm). As part of the mmap_prepare action functionality, we deal with errors by unmapping the VMA should one arise. This works in the usual mmap_prepare case, as we invoke this action at the last moment, when the VMA is established in the maple tree. However, the mmap() hook passes a not-fully-established VMA pointer to the caller (which is the motivation behind the mmap_prepare() work), which is detached. So attempting to unmap a VMA in this state will be problematic, with the most obvious symptom being a warning in vma_mark_detached(), because the VMA is already detached. It's also unncessary - the mmap() handler will clean up the VMA on error. So to fix this issue, this patch propagates whether or not an mmap action is being completed via the compatibility layer or directly. If the former, then we do not attempt VMA cleanup, if the latter, then we do. This patch also updates the userland VMA tests to reflect the change. Link: https://lore.kernel.org/20260421102150.189982-1-ljs@kernel.org Fixes: ac0a3fc9c07d ("mm: add ability to take further action in vm_area_desc") Signed-off-by: Lorenzo Stoakes Reported-by: syzbot+db390288d141a1dccf96@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69e69734.050a0220.24bfd3.0027.GAE@google.com/ Cc: David Hildenbrand Cc: Jann Horn Cc: Liam Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Pedro Falcato Cc: Suren Baghdasaryan Cc: Signed-off-by: Andrew Morton --- include/linux/mm.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/mm.h b/include/linux/mm.h index 0b776907152e..af23453e9dbd 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -4391,7 +4391,7 @@ static inline void mmap_action_map_kernel_pages_full(struct vm_area_desc *desc, int mmap_action_prepare(struct vm_area_desc *desc); int mmap_action_complete(struct vm_area_struct *vma, - struct mmap_action *action); + struct mmap_action *action, bool is_compat); /* Look up the first VMA which exactly match the interval vm_start ... vm_end */ static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm, -- cgit From 77a50e9652ac3c669c6690088bce97d960f5fd17 Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" Date: Wed, 22 Apr 2026 14:43:10 -0400 Subject: MAINTAINERS: update Liam's email address Switching to private email address. Update all contact information Add an entry to mailmap at the same time. Link: https://lore.kernel.org/20260422184310.2682901-1-liam@infradead.org Signed-off-by: Liam R. Howlett Signed-off-by: Andrew Morton --- .mailmap | 1 + MAINTAINERS | 20 ++++++++++---------- include/linux/maple_tree.h | 2 +- lib/maple_tree.c | 2 +- lib/test_maple_tree.c | 4 ++-- tools/testing/radix-tree/maple.c | 2 +- 6 files changed, 16 insertions(+), 15 deletions(-) (limited to 'include') diff --git a/.mailmap b/.mailmap index a8fd13adf226..f1eafd91d2c2 100644 --- a/.mailmap +++ b/.mailmap @@ -496,6 +496,7 @@ Leon Romanovsky Leon Romanovsky Leon Romanovsky Leo Yan +Liam R. Howlett Liam Mark Linas Vepstas Linus Lüssing diff --git a/MAINTAINERS b/MAINTAINERS index d6f017581d54..be2e017b3a9d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15399,7 +15399,7 @@ F: include/net/netns/mctp.h F: net/mctp/ MAPLE TREE -M: Liam R. Howlett +M: Liam R. Howlett R: Alice Ryhl R: Andrew Ballance L: maple-tree@lists.infradead.org @@ -16759,7 +16759,7 @@ MEMORY MANAGEMENT - CORE M: Andrew Morton M: David Hildenbrand R: Lorenzo Stoakes -R: Liam R. Howlett +R: Liam R. Howlett R: Vlastimil Babka R: Mike Rapoport R: Suren Baghdasaryan @@ -16895,7 +16895,7 @@ MEMORY MANAGEMENT - MISC M: Andrew Morton M: David Hildenbrand R: Lorenzo Stoakes -R: Liam R. Howlett +R: Liam R. Howlett R: Vlastimil Babka R: Mike Rapoport R: Suren Baghdasaryan @@ -16997,7 +16997,7 @@ M: Andrew Morton M: David Hildenbrand M: Lorenzo Stoakes R: Rik van Riel -R: Liam R. Howlett +R: Liam R. Howlett R: Vlastimil Babka R: Harry Yoo R: Jann Horn @@ -17044,7 +17044,7 @@ M: David Hildenbrand M: Lorenzo Stoakes R: Zi Yan R: Baolin Wang -R: Liam R. Howlett +R: Liam R. Howlett R: Nico Pache R: Ryan Roberts R: Dev Jain @@ -17082,7 +17082,7 @@ F: tools/testing/selftests/mm/uffd-*.[ch] MEMORY MANAGEMENT - RUST M: Alice Ryhl R: Lorenzo Stoakes -R: Liam R. Howlett +R: Liam R. Howlett L: linux-mm@kvack.org L: rust-for-linux@vger.kernel.org S: Maintained @@ -17096,7 +17096,7 @@ F: rust/kernel/page.rs MEMORY MAPPING M: Andrew Morton -M: Liam R. Howlett +M: Liam R. Howlett M: Lorenzo Stoakes R: Vlastimil Babka R: Jann Horn @@ -17128,7 +17128,7 @@ F: tools/testing/vma/ MEMORY MAPPING - LOCKING M: Andrew Morton M: Suren Baghdasaryan -M: Liam R. Howlett +M: Liam R. Howlett M: Lorenzo Stoakes R: Vlastimil Babka R: Shakeel Butt @@ -17143,7 +17143,7 @@ F: mm/mmap_lock.c MEMORY MAPPING - MADVISE (MEMORY ADVICE) M: Andrew Morton -M: Liam R. Howlett +M: Liam R. Howlett M: Lorenzo Stoakes M: David Hildenbrand R: Vlastimil Babka @@ -23370,7 +23370,7 @@ RUST [ALLOC] M: Danilo Krummrich R: Lorenzo Stoakes R: Vlastimil Babka -R: Liam R. Howlett +R: Liam R. Howlett R: Uladzislau Rezki L: rust-for-linux@vger.kernel.org S: Maintained diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h index 0c464eade1d6..4a5631906aff 100644 --- a/include/linux/maple_tree.h +++ b/include/linux/maple_tree.h @@ -4,7 +4,7 @@ /* * Maple Tree - An RCU-safe adaptive tree for storing ranges * Copyright (c) 2018-2022 Oracle - * Authors: Liam R. Howlett + * Authors: Liam R. Howlett * Matthew Wilcox */ diff --git a/lib/maple_tree.c b/lib/maple_tree.c index d18d7ed9ab67..60ae5e6fc1ee 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -2,7 +2,7 @@ /* * Maple Tree implementation * Copyright (c) 2018-2022 Oracle Corporation - * Authors: Liam R. Howlett + * Authors: Liam R. Howlett * Matthew Wilcox * Copyright (c) 2023 ByteDance * Author: Peng Zhang diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c index 434d8a2fdd99..b9367c61e8b5 100644 --- a/lib/test_maple_tree.c +++ b/lib/test_maple_tree.c @@ -2,7 +2,7 @@ /* * test_maple_tree.c: Test the maple tree API * Copyright (c) 2018-2022 Oracle Corporation - * Author: Liam R. Howlett + * Author: Liam R. Howlett * * Any tests that only require the interface of the tree. */ @@ -4021,6 +4021,6 @@ static void __exit maple_tree_harvest(void) module_init(maple_tree_seed); module_exit(maple_tree_harvest); -MODULE_AUTHOR("Liam R. Howlett "); +MODULE_AUTHOR("Liam R. Howlett "); MODULE_DESCRIPTION("maple tree API test module"); MODULE_LICENSE("GPL"); diff --git a/tools/testing/radix-tree/maple.c b/tools/testing/radix-tree/maple.c index feedd5ab7058..0607913a3022 100644 --- a/tools/testing/radix-tree/maple.c +++ b/tools/testing/radix-tree/maple.c @@ -2,7 +2,7 @@ /* * maple_tree.c: Userspace testing for maple tree test-suite * Copyright (c) 2018-2022 Oracle Corporation - * Author: Liam R. Howlett + * Author: Liam R. Howlett * * Any tests that require internal knowledge of the tree or threads and other * difficult to handle in kernel tests. -- cgit