kernel/linux.git/ipc/shm.c, branch v7.0-rc7

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

mm: update shmem_[kernel]_file_*() functions to use vma_flags_t

2026-02-12T23:42:58+00:00

In order to be able to use only vma_flags_t in vm_area_desc we must adjust shmem file setup functions to operate in terms of vma_flags_t rather than vm_flags_t. This patch makes this change and updates all callers to use the new functions. No functional changes intended. [akpm@linux-foundation.org: comment fixes, per Baolin] Link: https://lkml.kernel.org/r/736febd280eb484d79cef5cf55b8a6f79ad832d2.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Reviewed-by: Baolin Wang Reviewed-by: Jarkko Sakkinen Reviewed-by: Liam R. Howlett Cc: Barry Song Cc: David Hildenbrand Cc: Dev Jain Cc: Jason Gunthorpe Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Cc: "Darrick J. Wong" Cc: Damien Le Moal Cc: Yury Norov Cc: Chris Mason Cc: Pedro Falcato Signed-off-by: Andrew Morton

mm: update hugetlbfs to use VMA flags on mmap_prepare

2026-02-12T23:42:57+00:00

In order to update all mmap_prepare users to utilising the new VMA flags type vma_flags_t and associated helper functions, we start by updating hugetlbfs which has a lot of additional logic that requires updating to make this change. This is laying the groundwork for eliminating the vm_flags_t from struct vm_area_desc and using vma_flags_t only, which further lays the ground for removing the deprecated vm_flags_t type altogether. No functional changes intended. Link: https://lkml.kernel.org/r/9226bec80c9aa3447cc2b83354f733841dba8a50.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Cc: Baolin Wang Cc: Barry Song Cc: David Hildenbrand Cc: Dev Jain Cc: Jason Gunthorpe Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Cc: Damien Le Moal Cc: "Darrick J. Wong" Cc: Jarkko Sakkinen Cc: Yury Norov Cc: Chris Mason Cc: Pedro Falcato Signed-off-by: Andrew Morton

ipc: support ns lookup

2025-09-19T12:26:15+00:00

Support the generic ns lookup infrastructure to support file handles for namespaces. Signed-off-by: Christian Brauner

mm: rename call_mmap/mmap_prepare to vfs_mmap/mmap_prepare

2025-06-17T11:35:23+00:00

The call_mmap() function violates the existing convention in include/linux/fs.h whereby invocations of virtual file system hooks is performed by functions prefixed with vfs_xxx(). Correct this by renaming call_mmap() to vfs_mmap(). This also avoids confusion as to the fact that f_op->mmap_prepare may be invoked here. Also rename __call_mmap_prepare() function to vfs_mmap_prepare() and adjust to accept a file parameter, this is useful later for nested file systems. Finally, fix up the VMA userland tests and ensure the mmap_prepare -> mmap shim is implemented there. Signed-off-by: Lorenzo Stoakes Link: https://lore.kernel.org/8d389f4994fa736aa8f9172bef8533c10a9e9011.1750099179.git.lorenzo.stoakes@oracle.com Signed-off-by: Christian Brauner

ipc: fix to protect IPCS lookups using RCU

2025-05-12T00:54:11+00:00

syzbot reported that it discovered a use-after-free vulnerability, [0] [0]: https://lore.kernel.org/all/67af13f8.050a0220.21dd3.0038.GAE@google.com/ idr_for_each() is protected by rwsem, but this is not enough. If it is not protected by RCU read-critical region, when idr_for_each() calls radix_tree_node_free() through call_rcu() to free the radix_tree_node structure, the node will be freed immediately, and when reading the next node in radix_tree_for_each_slot(), the already freed memory may be read. Therefore, we need to add code to make sure that idr_for_each() is protected within the RCU read-critical region when we call it in shm_destroy_orphaned(). Link: https://lkml.kernel.org/r/20250424143322.18830-1-aha310510@gmail.com Fixes: b34a6b1da371 ("ipc: introduce shm_rmid_forced sysctl") Signed-off-by: Jeongjun Park Reported-by: syzbot+a2b84e569d06ca3a949c@syzkaller.appspotmail.com Cc: Jeongjun Park Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Matthew Wilcox (Oracle) Cc: Vasiliy Kulikov Cc: Signed-off-by: Andrew Morton

ipc/shm, mm: drop do_vma_munmap()

2024-09-04T04:15:52+00:00

The do_vma_munmap() wrapper existed for callers that didn't have a vma iterator and needed to check the vma mseal status prior to calling the underlying munmap(). All callers now use a vma iterator and since the mseal check has been moved to do_vmi_align_munmap() and the vmas are aligned, this function can just be called instead. do_vmi_align_munmap() can no longer be static as ipc/shm is using it and it is exported via the mm.h header. Link: https://lkml.kernel.org/r/20240830040101.822209-19-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Reviewed-by: Lorenzo Stoakes Cc: Bert Karwatzki Cc: Jeff Xu Cc: Jiri Olsa Cc: Kees Cook Cc: Lorenzo Stoakes Cc: Mark Brown Cc: Matthew Wilcox Cc: "Paul E. McKenney" Cc: Paul Moore Cc: Sidhartha Kumar Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

fs: Add FOP_HUGE_PAGES

2024-04-09T08:53:44+00:00

Instead of checking for specific file_operations, add a bit to file_operations which denotes a file that only contain hugetlb pages. This lets us make hugetlbfs_file_operations static, and removes is_file_shm_hugepages() completely. Signed-off-by: Matthew Wilcox (Oracle) Link: https://lore.kernel.org/r/20240407201122.3783877-1-willy@infradead.org Signed-off-by: Christian Brauner

shm: Slim down dependencies

2023-12-21T00:26:31+00:00

list_head is in types.h, not list.h., and the uapi header wasn't needed. Signed-off-by: Kent Overstreet