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2026-02-10Merge tag 'timers-vdso-2026-02-09' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull VDSO updates from Thomas Gleixner: - Provide the missing 64-bit variant of clock_getres() This allows the extension of CONFIG_COMPAT_32BIT_TIME to the vDSO and finally the removal of 32-bit time types from the kernel and UAPI. - Remove the useless and broken getcpu_cache from the VDSO The intention was to provide a trivial way to retrieve the CPU number from the VDSO, but as the VDSO data is per process there is no way to make it work. - Switch get/put_unaligned() from packed struct to memcpy() The packed struct violates strict aliasing rules which requires to pass -fno-strict-aliasing to the compiler. As this are scalar values __builtin_memcpy() turns them into simple loads and stores - Use __typeof_unqual__() for __unqual_scalar_typeof() The get/put_unaligned() changes triggered a new sparse warning when __beNN types are used with get/put_unaligned() as sparse builds add a special 'bitwise' attribute to them which prevents sparse to evaluate the Generic in __unqual_scalar_typeof(). Newer sparse versions support __typeof_unqual__() which avoids the problem, but requires a recent sparse install. So this adds a sanity check to sparse builds, which validates that sparse is available and capable of handling it. - Force inline __cvdso_clock_getres_common() Compilers sometimes un-inline agressively, which results in function call overhead and problems with automatic stack variable initialization. Interestingly enough the force inlining results in smaller code than the un-inlined variant produced by GCC when optimizing for size. * tag 'timers-vdso-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: vdso/gettimeofday: Force inlining of __cvdso_clock_getres_common() x86/percpu: Make CONFIG_USE_X86_SEG_SUPPORT work with sparse compiler: Use __typeof_unqual__() for __unqual_scalar_typeof() powerpc/vdso: Provide clock_getres_time64() tools headers: Remove unneeded ignoring of warnings in unaligned.h tools headers: Update the linux/unaligned.h copy with the kernel sources vdso: Switch get/put_unaligned() from packed struct to memcpy() parisc: Inline a type punning version of get_unaligned_le32() vdso: Remove struct getcpu_cache MIPS: vdso: Provide getres_time64() for 32-bit ABIs arm64: vdso32: Provide clock_getres_time64() ARM: VDSO: Provide clock_getres_time64() ARM: VDSO: Patch out __vdso_clock_getres() if unavailable x86/vdso: Provide clock_getres_time64() for x86-32 selftests: vDSO: vdso_test_abi: Add test for clock_getres_time64() selftests: vDSO: vdso_test_abi: Use UAPI system call numbers selftests: vDSO: vdso_config: Add configurations for clock_getres_time64() vdso: Add prototype for __vdso_clock_getres_time64()
2026-01-22rseq: Implement sys_rseq_slice_yield()Thomas Gleixner1-0/+1
Provide a new syscall which has the only purpose to yield the CPU after the kernel granted a time slice extension. sched_yield() is not suitable for that because it unconditionally schedules, but the end of the time slice extension is not required to schedule when the task was already preempted. This also allows to have a strict check for termination to catch user space invoking random syscalls including sched_yield() from a time slice extension region. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://patch.msgid.link/20251215155708.929634896@linutronix.de
2026-01-14vdso: Remove struct getcpu_cacheThomas Weißschuh1-2/+1
The cache parameter of getcpu() is useless nowadays for various reasons. * It is never passed by userspace for either the vDSO or syscalls. * It is never used by the kernel. * It could not be made to work on the current vDSO architecture. * The structure definition is not part of the UAPI headers. * vdso_getcpu() is superseded by restartable sequences in any case. Remove the struct and its header. As a side-effect this gets rid of an unwanted inclusion of the linux/ header namespace from vDSO code. [ tglx: Adapt to s390 upstream changes */ Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390 Link: https://patch.msgid.link/20251230-getcpu_cache-v3-1-fb9c5f880ebe@linutronix.de
2025-11-03nstree: add listns()Christian Brauner1-0/+4
Add a new listns() system call that allows userspace to iterate through namespaces in the system. This provides a programmatic interface to discover and inspect namespaces, enhancing existing namespace apis. Currently, there is no direct way for userspace to enumerate namespaces in the system. Applications must resort to scanning /proc/<pid>/ns/ across all processes, which is: 1. Inefficient - requires iterating over all processes 2. Incomplete - misses inactive namespaces that aren't attached to any running process but are kept alive by file descriptors, bind mounts, or parent namespace references 3. Permission-heavy - requires access to /proc for many processes 4. No ordering or ownership. 5. No filtering per namespace type: Must always iterate and check all namespaces. The list goes on. The listns() system call solves these problems by providing direct kernel-level enumeration of namespaces. It is similar to listmount() but obviously tailored to namespaces. /* * @req: Pointer to struct ns_id_req specifying search parameters * @ns_ids: User buffer to receive namespace IDs * @nr_ns_ids: Size of ns_ids buffer (maximum number of IDs to return) * @flags: Reserved for future use (must be 0) */ ssize_t listns(const struct ns_id_req *req, u64 *ns_ids, size_t nr_ns_ids, unsigned int flags); Returns: - On success: Number of namespace IDs written to ns_ids - On error: Negative error code /* * @size: Structure size * @ns_id: Starting point for iteration; use 0 for first call, then * use the last returned ID for subsequent calls to paginate * @ns_type: Bitmask of namespace types to include (from enum ns_type): * 0: Return all namespace types * MNT_NS: Mount namespaces * NET_NS: Network namespaces * USER_NS: User namespaces * etc. Can be OR'd together * @user_ns_id: Filter results to namespaces owned by this user namespace: * 0: Return all namespaces (subject to permission checks) * LISTNS_CURRENT_USER: Namespaces owned by caller's user namespace * Other value: Namespaces owned by the specified user namespace ID */ struct ns_id_req { __u32 size; /* sizeof(struct ns_id_req) */ __u32 spare; /* Reserved, must be 0 */ __u64 ns_id; /* Last seen namespace ID (for pagination) */ __u32 ns_type; /* Filter by namespace type(s) */ __u32 spare2; /* Reserved, must be 0 */ __u64 user_ns_id; /* Filter by owning user namespace */ }; Example 1: List all namespaces void list_all_namespaces(void) { struct ns_id_req req = { .size = sizeof(req), .ns_id = 0, /* Start from beginning */ .ns_type = 0, /* All types */ .user_ns_id = 0, /* All user namespaces */ }; uint64_t ids[100]; ssize_t ret; printf("All namespaces in the system:\n"); do { ret = listns(&req, ids, 100, 0); if (ret < 0) { perror("listns"); break; } for (ssize_t i = 0; i < ret; i++) printf(" Namespace ID: %llu\n", (unsigned long long)ids[i]); /* Continue from last seen ID */ if (ret > 0) req.ns_id = ids[ret - 1]; } while (ret == 100); /* Buffer was full, more may exist */ } Example 2: List network namespaces only void list_network_namespaces(void) { struct ns_id_req req = { .size = sizeof(req), .ns_id = 0, .ns_type = NET_NS, /* Only network namespaces */ .user_ns_id = 0, }; uint64_t ids[100]; ssize_t ret; ret = listns(&req, ids, 100, 0); if (ret < 0) { perror("listns"); return; } printf("Network namespaces: %zd found\n", ret); for (ssize_t i = 0; i < ret; i++) printf(" netns ID: %llu\n", (unsigned long long)ids[i]); } Example 3: List namespaces owned by current user namespace void list_owned_namespaces(void) { struct ns_id_req req = { .size = sizeof(req), .ns_id = 0, .ns_type = 0, /* All types */ .user_ns_id = LISTNS_CURRENT_USER, /* Current userns */ }; uint64_t ids[100]; ssize_t ret; ret = listns(&req, ids, 100, 0); if (ret < 0) { perror("listns"); return; } printf("Namespaces owned by my user namespace: %zd\n", ret); for (ssize_t i = 0; i < ret; i++) printf(" ns ID: %llu\n", (unsigned long long)ids[i]); } Example 4: List multiple namespace types void list_network_and_mount_namespaces(void) { struct ns_id_req req = { .size = sizeof(req), .ns_id = 0, .ns_type = NET_NS | MNT_NS, /* Network and mount */ .user_ns_id = 0, }; uint64_t ids[100]; ssize_t ret; ret = listns(&req, ids, 100, 0); printf("Network and mount namespaces: %zd found\n", ret); } Example 5: Pagination through large namespace sets void list_all_with_pagination(void) { struct ns_id_req req = { .size = sizeof(req), .ns_id = 0, .ns_type = 0, .user_ns_id = 0, }; uint64_t ids[50]; size_t total = 0; ssize_t ret; printf("Enumerating all namespaces with pagination:\n"); while (1) { ret = listns(&req, ids, 50, 0); if (ret < 0) { perror("listns"); break; } if (ret == 0) break; /* No more namespaces */ total += ret; printf(" Batch: %zd namespaces\n", ret); /* Last ID in this batch becomes start of next batch */ req.ns_id = ids[ret - 1]; if (ret < 50) break; /* Partial batch = end of results */ } printf("Total: %zu namespaces\n", total); } Permission Model listns() respects namespace isolation and capabilities: (1) Global listing (user_ns_id = 0): - Requires CAP_SYS_ADMIN in the namespace's owning user namespace - OR the namespace must be in the caller's namespace context (e.g., a namespace the caller is currently using) - User namespaces additionally allow listing if the caller has CAP_SYS_ADMIN in that user namespace itself (2) Owner-filtered listing (user_ns_id != 0): - Requires CAP_SYS_ADMIN in the specified owner user namespace - OR the namespace must be in the caller's namespace context - This allows unprivileged processes to enumerate namespaces they own (3) Visibility: - Only "active" namespaces are listed - A namespace is active if it has a non-zero __ns_ref_active count - This includes namespaces used by running processes, held by open file descriptors, or kept active by bind mounts - Inactive namespaces (kept alive only by internal kernel references) are not visible via listns() Link: https://patch.msgid.link/20251029-work-namespace-nstree-listns-v4-19-2e6f823ebdc0@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-21uprobes/x86: Add uprobe syscall to speed up uprobeJiri Olsa1-0/+2
Adding new uprobe syscall that calls uprobe handlers for given 'breakpoint' address. The idea is that the 'breakpoint' address calls the user space trampoline which executes the uprobe syscall. The syscall handler reads the return address of the initial call to retrieve the original 'breakpoint' address. With this address we find the related uprobe object and call its consumers. Adding the arch_uprobe_trampoline_mapping function that provides uprobe trampoline mapping. This mapping is backed with one global page initialized at __init time and shared by the all the mapping instances. We do not allow to execute uprobe syscall if the caller is not from uprobe trampoline mapping. The uprobe syscall ensures the consumer (bpf program) sees registers values in the state before the trampoline was called. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20250720112133.244369-10-jolsa@kernel.org
2025-07-02fs: introduce file_getattr and file_setattr syscallsAndrey Albershteyn1-0/+7
Introduce file_getattr() and file_setattr() syscalls to manipulate inode extended attributes. The syscalls takes pair of file descriptor and pathname. Then it operates on inode opened accroding to openat() semantics. The struct file_attr is passed to obtain/change extended attributes. This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference that file don't need to be open as we can reference it with a path instead of fd. By having this we can manipulated inode extended attributes not only on regular files but also on special ones. This is not possible with FS_IOC_FSSETXATTR ioctl as with special files we can not call ioctl() directly on the filesystem inode using fd. This patch adds two new syscalls which allows userspace to get/set extended inode attributes on special files by using parent directory and a path - *at() like syscall. CC: linux-api@vger.kernel.org CC: linux-fsdevel@vger.kernel.org CC: linux-xfs@vger.kernel.org Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org> Link: https://lore.kernel.org/20250630-xattrat-syscall-v6-6-c4e3bc35227b@kernel.org Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-24Merge tag 'vfs-6.15-rc1.mount' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs mount updates from Christian Brauner: - Mount notifications The day has come where we finally provide a new api to listen for mount topology changes outside of /proc/<pid>/mountinfo. A mount namespace file descriptor can be supplied and registered with fanotify to listen for mount topology changes. Currently notifications for mount, umount and moving mounts are generated. The generated notification record contains the unique mount id of the mount. The listmount() and statmount() api can be used to query detailed information about the mount using the received unique mount id. This allows userspace to figure out exactly how the mount topology changed without having to generating diffs of /proc/<pid>/mountinfo in userspace. - Support O_PATH file descriptors with FSCONFIG_SET_FD in the new mount api - Support detached mounts in overlayfs Since last cycle we support specifying overlayfs layers via file descriptors. However, we don't allow detached mounts which means userspace cannot user file descriptors received via open_tree(OPEN_TREE_CLONE) and fsmount() directly. They have to attach them to a mount namespace via move_mount() first. This is cumbersome and means they have to undo mounts via umount(). Allow them to directly use detached mounts. - Allow to retrieve idmappings with statmount Currently it isn't possible to figure out what idmapping has been attached to an idmapped mount. Add an extension to statmount() which allows to read the idmapping from the mount. - Allow creating idmapped mounts from mounts that are already idmapped So far it isn't possible to allow the creation of idmapped mounts from already idmapped mounts as this has significant lifetime implications. Make the creation of idmapped mounts atomic by allow to pass struct mount_attr together with the open_tree_attr() system call allowing to solve these issues without complicating VFS lookup in any way. The system call has in general the benefit that creating a detached mount and applying mount attributes to it becomes an atomic operation for userspace. - Add a way to query statmount() for supported options Allow userspace to query which mount information can be retrieved through statmount(). - Allow superblock owners to force unmount * tag 'vfs-6.15-rc1.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (21 commits) umount: Allow superblock owners to force umount selftests: add tests for mount notification selinux: add FILE__WATCH_MOUNTNS samples/vfs: fix printf format string for size_t fs: allow changing idmappings fs: add kflags member to struct mount_kattr fs: add open_tree_attr() fs: add copy_mount_setattr() helper fs: add vfs_open_tree() helper statmount: add a new supported_mask field samples/vfs: add STATMOUNT_MNT_{G,U}IDMAP selftests: add tests for using detached mount with overlayfs samples/vfs: check whether flag was raised statmount: allow to retrieve idmappings uidgid: add map_id_range_up() fs: allow detached mounts in clone_private_mount() selftests/overlayfs: test specifying layers as O_PATH file descriptors fs: support O_PATH fds with FSCONFIG_SET_FD vfs: add notifications for mount attach and detach fanotify: notify on mount attach and detach ...
2025-02-21open: Fix return type of several functions from long to intYuichiro Tsuji1-2/+2
Fix the return type of several functions from long to int to match its actu al behavior. These functions only return int values. This change improves type consistency across the filesystem code and aligns the function signatu re with its existing implementation and usage. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Yuichiro Tsuji <yuichtsu@amazon.com> Link: https://lore.kernel.org/r/20250121070844.4413-2-yuichtsu@amazon.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-12fs: add open_tree_attr()Christian Brauner1-0/+4
Add open_tree_attr() which allow to atomically create a detached mount tree and set mount options on it. If OPEN_TREE_CLONE is used this will allow the creation of a detached mount with a new set of mount options without it ever being exposed to userspace without that set of mount options applied. Link: https://lore.kernel.org/r/20250128-work-mnt_idmap-update-v2-v1-3-c25feb0d2eb3@kernel.org Reviewed-by: "Seth Forshee (DigitalOcean)" <sforshee@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-11-06fs/xattr: add *at family syscallsChristian Göttsche1-0/+13
Add the four syscalls setxattrat(), getxattrat(), listxattrat() and removexattrat(). Those can be used to operate on extended attributes, especially security related ones, either relative to a pinned directory or on a file descriptor without read access, avoiding a /proc/<pid>/fd/<fd> detour, requiring a mounted procfs. One use case will be setfiles(8) setting SELinux file contexts ("security.selinux") without race conditions and without a file descriptor opened with read access requiring SELinux read permission. Use the do_{name}at() pattern from fs/open.c. Pass the value of the extended attribute, its length, and for setxattrat(2) the command (XATTR_CREATE or XATTR_REPLACE) via an added struct xattr_args to not exceed six syscall arguments and not merging the AT_* and XATTR_* flags. [AV: fixes by Christian Brauner folded in, the entire thing rebased on top of {filename,file}_...xattr() primitives, treatment of empty pathnames regularized. As the result, AT_EMPTY_PATH+NULL handling is cheap, so f...(2) can use it] Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Link: https://lore.kernel.org/r/20240426162042.191916-1-cgoettsche@seltendoof.de Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christian Brauner <brauner@kernel.org> CC: x86@kernel.org CC: linux-alpha@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-ia64@vger.kernel.org CC: linux-m68k@lists.linux-m68k.org CC: linux-mips@vger.kernel.org CC: linux-parisc@vger.kernel.org CC: linuxppc-dev@lists.ozlabs.org CC: linux-s390@vger.kernel.org CC: linux-sh@vger.kernel.org CC: sparclinux@vger.kernel.org CC: linux-fsdevel@vger.kernel.org CC: audit@vger.kernel.org CC: linux-arch@vger.kernel.org CC: linux-api@vger.kernel.org CC: linux-security-module@vger.kernel.org CC: selinux@vger.kernel.org [brauner: slight tweaks] Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-09-05fhandle: expose u64 mount id to name_to_handle_at(2)Aleksa Sarai1-1/+1
Now that we provide a unique 64-bit mount ID interface in statx(2), we can now provide a race-free way for name_to_handle_at(2) to provide a file handle and corresponding mount without needing to worry about racing with /proc/mountinfo parsing or having to open a file just to do statx(2). While this is not necessary if you are using AT_EMPTY_PATH and don't care about an extra statx(2) call, users that pass full paths into name_to_handle_at(2) need to know which mount the file handle comes from (to make sure they don't try to open_by_handle_at a file handle from a different filesystem) and switching to AT_EMPTY_PATH would require allocating a file for every name_to_handle_at(2) call, turning err = name_to_handle_at(-EBADF, "/foo/bar/baz", &handle, &mntid, AT_HANDLE_MNT_ID_UNIQUE); into int fd = openat(-EBADF, "/foo/bar/baz", O_PATH | O_CLOEXEC); err1 = name_to_handle_at(fd, "", &handle, &unused_mntid, AT_EMPTY_PATH); err2 = statx(fd, "", AT_EMPTY_PATH, STATX_MNT_ID_UNIQUE, &statxbuf); mntid = statxbuf.stx_mnt_id; close(fd); Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Aleksa Sarai <cyphar@cyphar.com> Link: https://lore.kernel.org/r/20240828-exportfs-u64-mount-id-v3-2-10c2c4c16708@cyphar.com Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-07-18Merge tag 'probes-v6.11' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: "Uprobes: - x86/shstk: Make return uprobe work with shadow stack - Add uretprobe syscall which speeds up the uretprobe 10-30% faster. This syscall is automatically used from user-space trampolines which are generated by the uretprobe. If this syscall is used by normal user program, it will cause SIGILL. Note that this is currently only implemented on x86_64. (This also has two fixes for adjusting the syscall number to avoid conflict with new *attrat syscalls.) - uprobes/perf: fix user stack traces in the presence of pending uretprobe. This corrects the uretprobe's trampoline address in the stacktrace with correct return address - selftests/x86: Add a return uprobe with shadow stack test - selftests/bpf: Add uretprobe syscall related tests. - test case for register integrity check - test case with register changing case - test case for uretprobe syscall without uprobes (expected to fail) - test case for uretprobe with shadow stack - selftests/bpf: add test validating uprobe/uretprobe stack traces - MAINTAINERS: Add uprobes entry. This does not specify the tree but to clarify who maintains and reviews the uprobes Kprobes: - tracing/kprobes: Test case cleanups. Replace redundant WARN_ON_ONCE() + pr_warn() with WARN_ONCE() and remove unnecessary code from selftest - tracing/kprobes: Add symbol counting check when module loads. This checks the uniqueness of the probed symbol on modules. The same check has already done for kernel symbols (This also has a fix for build error with CONFIG_MODULES=n) Cleanup: - Add MODULE_DESCRIPTION() macros for fprobe and kprobe examples" * tag 'probes-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: MAINTAINERS: Add uprobes entry selftests/bpf: Change uretprobe syscall number in uprobe_syscall test uprobe: Change uretprobe syscall scope and number tracing/kprobes: Fix build error when find_module() is not available tracing/kprobes: Add symbol counting check when module loads selftests/bpf: add test validating uprobe/uretprobe stack traces perf,uprobes: fix user stack traces in the presence of pending uretprobes tracing/kprobe: Remove cleanup code unrelated to selftest tracing/kprobe: Integrate test warnings into WARN_ONCE selftests/bpf: Add uretprobe shadow stack test selftests/bpf: Add uretprobe syscall call from user space test selftests/bpf: Add uretprobe syscall test for regs changes selftests/bpf: Add uretprobe syscall test for regs integrity selftests/x86: Add return uprobe shadow stack test uprobe: Add uretprobe syscall to speed up return probe uprobe: Wire up uretprobe system call x86/shstk: Make return uprobe work with shadow stack samples: kprobes: add missing MODULE_DESCRIPTION() macros fprobe: add missing MODULE_DESCRIPTION() macro
2024-07-01syscalls: fix sys_fanotify_mark prototypeArnd Bergmann1-0/+6
My earlier fix missed an incorrect function prototype that shows up on native 32-bit builds: In file included from fs/notify/fanotify/fanotify_user.c:14: include/linux/syscalls.h:248:25: error: conflicting types for 'sys_fanotify_mark'; have 'long int(int, unsigned int, u32, u32, int, const char *)' {aka 'long int(int, unsigned int, unsigned int, unsigned int, int, const char *)'} 1924 | SYSCALL32_DEFINE6(fanotify_mark, | ^~~~~~~~~~~~~~~~~ include/linux/syscalls.h:862:17: note: previous declaration of 'sys_fanotify_mark' with type 'long int(int, unsigned int, u64, int, const char *)' {aka 'long int(int, unsigned int, long long unsigned int, int, const char *)'} On x86 and powerpc, the prototype is also wrong but hidden in an #ifdef, so it never caused problems. Add another alternative declaration that matches the conditional function definition. Fixes: 403f17a33073 ("parisc: use generic sys_fanotify_mark implementation") Cc: stable@vger.kernel.org Reported-by: Guenter Roeck <linux@roeck-us.net> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-06-25linux/syscalls.h: add missing __user annotationsArnd Bergmann1-9/+9
A couple of declarations in linux/syscalls.h are missing __user annotations on their pointers, which can lead to warnings from sparse because these don't match the implementation that have the correct address space annotations. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-06-24ftruncate: pass a signed offsetArnd Bergmann1-1/+1
The old ftruncate() syscall, using the 32-bit off_t misses a sign extension when called in compat mode on 64-bit architectures. As a result, passing a negative length accidentally succeeds in truncating to file size between 2GiB and 4GiB. Changing the type of the compat syscall to the signed compat_off_t changes the behavior so it instead returns -EINVAL. The native entry point, the truncate() syscall and the corresponding loff_t based variants are all correct already and do not suffer from this mistake. Fixes: 3f6d078d4acc ("fix compat truncate/ftruncate") Reviewed-by: Christian Brauner <brauner@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-06-12uprobe: Wire up uretprobe system callJiri Olsa1-0/+2
Wiring up uretprobe system call, which comes in following changes. We need to do the wiring before, because the uretprobe implementation needs the syscall number. Note at the moment uretprobe syscall is supported only for native 64-bit process. Link: https://lore.kernel.org/all/20240611112158.40795-3-jolsa@kernel.org/ Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-05-23mseal: add mseal syscallJeff Xu1-0/+1
The new mseal() is an syscall on 64 bit CPU, and with following signature: int mseal(void addr, size_t len, unsigned long flags) addr/len: memory range. flags: reserved. mseal() blocks following operations for the given memory range. 1> Unmapping, moving to another location, and shrinking the size, via munmap() and mremap(), can leave an empty space, therefore can be replaced with a VMA with a new set of attributes. 2> Moving or expanding a different VMA into the current location, via mremap(). 3> Modifying a VMA via mmap(MAP_FIXED). 4> Size expansion, via mremap(), does not appear to pose any specific risks to sealed VMAs. It is included anyway because the use case is unclear. In any case, users can rely on merging to expand a sealed VMA. 5> mprotect() and pkey_mprotect(). 6> Some destructive madvice() behaviors (e.g. MADV_DONTNEED) for anonymous memory, when users don't have write permission to the memory. Those behaviors can alter region contents by discarding pages, effectively a memset(0) for anonymous memory. Following input during RFC are incooperated into this patch: Jann Horn: raising awareness and providing valuable insights on the destructive madvise operations. Linus Torvalds: assisting in defining system call signature and scope. Liam R. Howlett: perf optimization. Theo de Raadt: sharing the experiences and insight gained from implementing mimmutable() in OpenBSD. Finally, the idea that inspired this patch comes from Stephen Röttger's work in Chrome V8 CFI. [jeffxu@chromium.org: add branch prediction hint, per Pedro] Link: https://lkml.kernel.org/r/20240423192825.1273679-2-jeffxu@chromium.org Link: https://lkml.kernel.org/r/20240415163527.626541-3-jeffxu@chromium.org Signed-off-by: Jeff Xu <jeffxu@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guenter Roeck <groeck@chromium.org> Cc: Jann Horn <jannh@google.com> Cc: Jeff Xu <jeffxu@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jorge Lucangeli Obes <jorgelo@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Muhammad Usama Anjum <usama.anjum@collabora.com> Cc: Pedro Falcato <pedro.falcato@gmail.com> Cc: Stephen Röttger <sroettger@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Amer Al Shanawany <amer.shanawany@gmail.com> Cc: Javier Carrasco <javier.carrasco.cruz@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-14lsm: use 32-bit compatible data types in LSM syscallsCasey Schaufler1-3/+3
Change the size parameters in lsm_list_modules(), lsm_set_self_attr() and lsm_get_self_attr() from size_t to u32. This avoids the need to have different interfaces for 32 and 64 bit systems. Cc: stable@vger.kernel.org Fixes: a04a1198088a ("LSM: syscalls for current process attributes") Fixes: ad4aff9ec25f ("LSM: Create lsm_list_modules system call") Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reported-and-reviewed-by: Dmitry V. Levin <ldv@strace.io> [PM: subject and metadata tweaks, syscall.h fixes] Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-01-24x86/entry/ia32: Ensure s32 is sign extended to s64Richard Palethorpe1-0/+1
Presently ia32 registers stored in ptregs are unconditionally cast to unsigned int by the ia32 stub. They are then cast to long when passed to __se_sys*, but will not be sign extended. This takes the sign of the syscall argument into account in the ia32 stub. It still casts to unsigned int to avoid implementation specific behavior. However then casts to int or unsigned int as necessary. So that the following cast to long sign extends the value. This fixes the io_pgetevents02 LTP test when compiled with -m32. Presently the systemcall io_pgetevents_time64() unexpectedly accepts -1 for the maximum number of events. It doesn't appear other systemcalls with signed arguments are effected because they all have compat variants defined and wired up. Fixes: ebeb8c82ffaf ("syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32") Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com> Signed-off-by: Nikolay Borisov <nik.borisov@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240110130122.3836513-1-nik.borisov@suse.com Link: https://lore.kernel.org/ltp/20210921130127.24131-1-rpalethorpe@suse.com/
2024-01-13fs: rework listmount() implementationChristian Brauner1-1/+1
Linus pointed out that there's error handling and naming issues in the that we should rewrite: * Perform the access checks for the buffer before actually doing any work instead of doing it during the iteration. * Rename the arguments to listmount() and do_listmount() to clarify what the arguments are used for. * Get rid of the pointless ctr variable and overflow checking. * Get rid of the pointless speculation check. Link: https://lore.kernel.org/r/CAHk-=wjh6Cypo8WC-McXgSzCaou3UXccxB+7PVeSuGR8AjCphg@mail.gmail.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-01-09Merge tag 'lsm-pr-20240105' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm Pull security module updates from Paul Moore: - Add three new syscalls: lsm_list_modules(), lsm_get_self_attr(), and lsm_set_self_attr(). The first syscall simply lists the LSMs enabled, while the second and third get and set the current process' LSM attributes. Yes, these syscalls may provide similar functionality to what can be found under /proc or /sys, but they were designed to support multiple, simultaneaous (stacked) LSMs from the start as opposed to the current /proc based solutions which were created at a time when only one LSM was allowed to be active at a given time. We have spent considerable time discussing ways to extend the existing /proc interfaces to support multiple, simultaneaous LSMs and even our best ideas have been far too ugly to support as a kernel API; after +20 years in the kernel, I felt the LSM layer had established itself enough to justify a handful of syscalls. Support amongst the individual LSM developers has been nearly unanimous, with a single objection coming from Tetsuo (TOMOYO) as he is worried that the LSM_ID_XXX token concept will make it more difficult for out-of-tree LSMs to survive. Several members of the LSM community have demonstrated the ability for out-of-tree LSMs to continue to exist by picking high/unused LSM_ID values as well as pointing out that many kernel APIs rely on integer identifiers, e.g. syscalls (!), but unfortunately Tetsuo's objections remain. My personal opinion is that while I have no interest in penalizing out-of-tree LSMs, I'm not going to penalize in-tree development to support out-of-tree development, and I view this as a necessary step forward to support the push for expanded LSM stacking and reduce our reliance on /proc and /sys which has occassionally been problematic for some container users. Finally, we have included the linux-api folks on (all?) recent revisions of the patchset and addressed all of their concerns. - Add a new security_file_ioctl_compat() LSM hook to handle the 32-bit ioctls on 64-bit systems problem. This patch includes support for all of the existing LSMs which provide ioctl hooks, although it turns out only SELinux actually cares about the individual ioctls. It is worth noting that while Casey (Smack) and Tetsuo (TOMOYO) did not give explicit ACKs to this patch, they did both indicate they are okay with the changes. - Fix a potential memory leak in the CALIPSO code when IPv6 is disabled at boot. While it's good that we are fixing this, I doubt this is something users are seeing in the wild as you need to both disable IPv6 and then attempt to configure IPv6 labeled networking via NetLabel/CALIPSO; that just doesn't make much sense. Normally this would go through netdev, but Jakub asked me to take this patch and of all the trees I maintain, the LSM tree seemed like the best fit. - Update the LSM MAINTAINERS entry with additional information about our process docs, patchwork, bug reporting, etc. I also noticed that the Lockdown LSM is missing a dedicated MAINTAINERS entry so I've added that to the pull request. I've been working with one of the major Lockdown authors/contributors to see if they are willing to step up and assume a Lockdown maintainer role; hopefully that will happen soon, but in the meantime I'll continue to look after it. - Add a handful of mailmap entries for Serge Hallyn and myself. * tag 'lsm-pr-20240105' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (27 commits) lsm: new security_file_ioctl_compat() hook lsm: Add a __counted_by() annotation to lsm_ctx.ctx calipso: fix memory leak in netlbl_calipso_add_pass() selftests: remove the LSM_ID_IMA check in lsm/lsm_list_modules_test MAINTAINERS: add an entry for the lockdown LSM MAINTAINERS: update the LSM entry mailmap: add entries for Serge Hallyn's dead accounts mailmap: update/replace my old email addresses lsm: mark the lsm_id variables are marked as static lsm: convert security_setselfattr() to use memdup_user() lsm: align based on pointer length in lsm_fill_user_ctx() lsm: consolidate buffer size handling into lsm_fill_user_ctx() lsm: correct error codes in security_getselfattr() lsm: cleanup the size counters in security_getselfattr() lsm: don't yet account for IMA in LSM_CONFIG_COUNT calculation lsm: drop LSM_ID_IMA LSM: selftests for Linux Security Module syscalls SELinux: Add selfattr hooks AppArmor: Add selfattr hooks Smack: implement setselfattr and getselfattr hooks ...
2023-12-14add listmount(2) syscallMiklos Szeredi1-0/+3
Add way to query the children of a particular mount. This is a more flexible way to iterate the mount tree than having to parse /proc/self/mountinfo. Lookup the mount by the new 64bit mount ID. If a mount needs to be queried based on path, then statx(2) can be used to first query the mount ID belonging to the path. Return an array of new (64bit) mount ID's. Without privileges only mounts are listed which are reachable from the task's root. Folded into this patch are several later improvements. Keeping them separate would make the history pointlessly confusing: * Recursive listing of mounts is the default now (cf. [1]). * Remove explicit LISTMOUNT_UNREACHABLE flag (cf. [1]) and fail if mount is unreachable from current root. This also makes permission checking consistent with statmount() (cf. [3]). * Start listing mounts in unique mount ID order (cf. [2]) to allow continuing listmount() from a midpoint. * Allow to continue listmount(). The @request_mask parameter is renamed and to @param to be usable by both statmount() and listmount(). If @param is set to a mount id then listmount() will continue listing mounts from that id on. This allows listing mounts in multiple listmount invocations without having to resize the buffer. If @param is zero then the listing starts from the beginning (cf. [4]). * Don't return EOVERFLOW, instead return the buffer size which allows to detect a full buffer as well (cf. [4]). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Link: https://lore.kernel.org/r/20231025140205.3586473-6-mszeredi@redhat.com Reviewed-by: Ian Kent <raven@themaw.net> Link: https://lore.kernel.org/r/20231128160337.29094-2-mszeredi@redhat.com [1] (folded) Link: https://lore.kernel.org/r/20231128160337.29094-3-mszeredi@redhat.com [2] (folded) Link: https://lore.kernel.org/r/20231128160337.29094-4-mszeredi@redhat.com [3] (folded) Link: https://lore.kernel.org/r/20231128160337.29094-5-mszeredi@redhat.com [4] (folded) [Christian Brauner <brauner@kernel.org>: various smaller fixes] Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-11add statmount(2) syscallMiklos Szeredi1-0/+5
Add a way to query attributes of a single mount instead of having to parse the complete /proc/$PID/mountinfo, which might be huge. Lookup the mount the new 64bit mount ID. If a mount needs to be queried based on path, then statx(2) can be used to first query the mount ID belonging to the path. Design is based on a suggestion by Linus: "So I'd suggest something that is very much like "statfsat()", which gets a buffer and a length, and returns an extended "struct statfs" *AND* just a string description at the end." The interface closely mimics that of statx. Handle ASCII attributes by appending after the end of the structure (as per above suggestion). Pointers to strings are stored in u64 members to make the structure the same regardless of pointer size. Strings are nul terminated. Link: https://lore.kernel.org/all/CAHk-=wh5YifP7hzKSbwJj94+DZ2czjrZsczy6GBimiogZws=rg@mail.gmail.com/ Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Link: https://lore.kernel.org/r/20231025140205.3586473-5-mszeredi@redhat.com Reviewed-by: Ian Kent <raven@themaw.net> [Christian Brauner <brauner@kernel.org>: various minor changes] Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-11-12LSM: Create lsm_list_modules system callCasey Schaufler1-0/+1
Create a system call to report the list of Linux Security Modules that are active on the system. The list is provided as an array of LSM ID numbers. The calling application can use this list determine what LSM specific actions it might take. That might include choosing an output format, determining required privilege or bypassing security module specific behavior. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: John Johansen <john.johansen@canonical.com> Reviewed-by: Mickaël Salaün <mic@digikod.net> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12LSM: syscalls for current process attributesCasey Schaufler1-0/+5
Create a system call lsm_get_self_attr() to provide the security module maintained attributes of the current process. Create a system call lsm_set_self_attr() to set a security module maintained attribute of the current process. Historically these attributes have been exposed to user space via entries in procfs under /proc/self/attr. The attribute value is provided in a lsm_ctx structure. The structure identifies the size of the attribute, and the attribute value. The format of the attribute value is defined by the security module. A flags field is included for LSM specific information. It is currently unused and must be 0. The total size of the data, including the lsm_ctx structure and any padding, is maintained as well. struct lsm_ctx { __u64 id; __u64 flags; __u64 len; __u64 ctx_len; __u8 ctx[]; }; Two new LSM hooks are used to interface with the LSMs. security_getselfattr() collects the lsm_ctx values from the LSMs that support the hook, accounting for space requirements. security_setselfattr() identifies which LSM the attribute is intended for and passes it along. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-01Merge tag 'asm-generic-6.7' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull ia64 removal and asm-generic updates from Arnd Bergmann: - The ia64 architecture gets its well-earned retirement as planned, now that there is one last (mostly) working release that will be maintained as an LTS kernel. - The architecture specific system call tables are updated for the added map_shadow_stack() syscall and to remove references to the long-gone sys_lookup_dcookie() syscall. * tag 'asm-generic-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: hexagon: Remove unusable symbols from the ptrace.h uapi asm-generic: Fix spelling of architecture arch: Reserve map_shadow_stack() syscall number for all architectures syscalls: Cleanup references to sys_lookup_dcookie() Documentation: Drop or replace remaining mentions of IA64 lib/raid6: Drop IA64 support Documentation: Drop IA64 from feature descriptions kernel: Drop IA64 support from sig_fault handlers arch: Remove Itanium (IA-64) architecture
2023-10-03syscalls: Cleanup references to sys_lookup_dcookie()Sohil Mehta1-1/+0
commit 'be65de6b03aa ("fs: Remove dcookies support")' removed the syscall definition for lookup_dcookie. However, syscall tables still point to the old sys_lookup_dcookie() definition. Update syscall tables of all architectures to directly point to sys_ni_syscall() instead. Signed-off-by: Sohil Mehta <sohil.mehta@intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Namhyung Kim <namhyung@kernel.org> # for perf Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-09-21futex: Add sys_futex_requeue()peterz@infradead.org1-0/+3
Finish off the 'simple' futex2 syscall group by adding sys_futex_requeue(). Unlike sys_futex_{wait,wake}() its arguments are too numerous to fit into a regular syscall. As such, use struct futex_waitv to pass the 'source' and 'destination' futexes to the syscall. This syscall implements what was previously known as FUTEX_CMP_REQUEUE and uses {val, uaddr, flags} for source and {uaddr, flags} for destination. This design explicitly allows requeueing between different types of futex by having a different flags word per uaddr. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230921105248.511860556@noisy.programming.kicks-ass.net
2023-09-21futex: Add sys_futex_wait()peterz@infradead.org1-0/+4
To complement sys_futex_waitv()/wake(), add sys_futex_wait(). This syscall implements what was previously known as FUTEX_WAIT_BITSET except it uses 'unsigned long' for the value and bitmask arguments, takes timespec and clockid_t arguments for the absolute timeout and uses FUTEX2 flags. The 'unsigned long' allows FUTEX2_SIZE_U64 on 64bit platforms. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230921105248.164324363@noisy.programming.kicks-ass.net
2023-09-21futex: Add sys_futex_wake()peterz@infradead.org1-0/+3
To complement sys_futex_waitv() add sys_futex_wake(). This syscall implements what was previously known as FUTEX_WAKE_BITSET except it uses 'unsigned long' for the bitmask and takes FUTEX2 flags. The 'unsigned long' allows FUTEX2_SIZE_U64 on 64bit platforms. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230921105247.936205525@noisy.programming.kicks-ass.net
2023-08-31Merge tag 'x86_shstk_for_6.6-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 shadow stack support from Dave Hansen: "This is the long awaited x86 shadow stack support, part of Intel's Control-flow Enforcement Technology (CET). CET consists of two related security features: shadow stacks and indirect branch tracking. This series implements just the shadow stack part of this feature, and just for userspace. The main use case for shadow stack is