kernel/linux.git/fs/proc/base.c, branch v6.19.11

proc: Fix pointer error dereference

2026-03-04T12:20:52+00:00

[ Upstream commit f6a495484a27150fb85f943e1a7464da88c2a797 ] The function try_lookup_noperm() can return an error pointer. Add check for error pointer. Detected by Smatch: fs/proc/base.c:2148 proc_fill_cache() error: 'child' dereferencing possible ERR_PTR() Fixes: 1df98b8bbcca ("proc_fill_cache(): clean up, get rid of pointless find_inode_number() use") Signed-off-by: Ethan Tidmore Link: https://patch.msgid.link/20260219221001.1117135-1-ethantidmore06@gmail.com Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2025-12-05T22:36:21+00:00

Pull persistent dentry infrastructure and conversion from Al Viro: "Some filesystems use a kinda-sorta controlled dentry refcount leak to pin dentries of created objects in dcache (and undo it when removing those). A reference is grabbed and not released, but it's not actually _stored_ anywhere. That works, but it's hard to follow and verify; among other things, we have no way to tell _which_ of the increments is intended to be an unpaired one. Worse, on removal we need to decide whether the reference had already been dropped, which can be non-trivial if that removal is on umount and we need to figure out if this dentry is pinned due to e.g. unlink() not done. Usually that is handled by using kill_litter_super() as ->kill_sb(), but there are open-coded special cases of the same (consider e.g. /proc/self). Things get simpler if we introduce a new dentry flag (DCACHE_PERSISTENT) marking those "leaked" dentries. Having it set claims responsibility for +1 in refcount. The end result this series is aiming for: - get these unbalanced dget() and dput() replaced with new primitives that would, in addition to adjusting refcount, set and clear persistency flag. - instead of having kill_litter_super() mess with removing the remaining "leaked" references (e.g. for all tmpfs files that hadn't been removed prior to umount), have the regular shrink_dcache_for_umount() strip DCACHE_PERSISTENT of all dentries, dropping the corresponding reference if it had been set. After that kill_litter_super() becomes an equivalent of kill_anon_super(). Doing that in a single step is not feasible - it would affect too many places in too many filesystems. It has to be split into a series. This work has really started early in 2024; quite a few preliminary pieces have already gone into mainline. This chunk is finally getting to the meat of that stuff - infrastructure and most of the conversions to it. Some pieces are still sitting in the local branches, but the bulk of that stuff is here" * tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) d_make_discardable(): warn if given a non-persistent dentry kill securityfs_recursive_remove() convert securityfs get rid of kill_litter_super() convert rust_binderfs convert nfsctl convert rpc_pipefs convert hypfs hypfs: swich hypfs_create_u64() to returning int hypfs: switch hypfs_create_str() to returning int hypfs: don't pin dentries twice convert gadgetfs gadgetfs: switch to simple_remove_by_name() convert functionfs functionfs: switch to simple_remove_by_name() functionfs: fix the open/removal races functionfs: need to cancel ->reset_work in ->kill_sb() functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}() functionfs: don't abuse ffs_data_closed() on fs shutdown convert selinuxfs ...

procfs: make /self and /thread_self dentries persistent

2025-11-16T06:35:02+00:00

... and there's no need to remember those pointers anywhere - ->kill_sb() no longer needs to bother since kill_anon_super() will take care of them anyway and proc_pid_readdir() only wants the inumbers, which we had in a couple of static variables all along. Signed-off-by: Al Viro

seqlock: Change do_io_accounting() to use scoped_seqlock_read()

2025-10-21T10:31:57+00:00

To simplify the code and make it more readable. [peterz: change to new interface] Signed-off-by: Oleg Nesterov Signed-off-by: Peter Zijlstra (Intel)

Merge tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-10-03T01:44:54+00:00

Pull non-MM updates from Andrew Morton: - "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet completes the removal of this legacy IDR API - "panic: introduce panic status function family" from Jinchao Wang provides a number of cleanups to the panic code and its various helpers, which were rather ad-hoc and scattered all over the place - "tools/delaytop: implement real-time keyboard interaction support" from Fan Yu adds a few nice user-facing usability changes to the delaytop monitoring tool - "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos Petrongonas fixes a panic which was happening with the combination of EFI and KHO - "Squashfs: performance improvement and a sanity check" from Phillip Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere 150x speedup was measured for a well-chosen microbenchmark - plus another 50-odd singleton patches all over the place * tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (75 commits) Squashfs: reject negative file sizes in squashfs_read_inode() kallsyms: use kmalloc_array() instead of kmalloc() MAINTAINERS: update Sibi Sankar's email address Squashfs: add SEEK_DATA/SEEK_HOLE support Squashfs: add additional inode sanity checking lib/genalloc: fix device leak in of_gen_pool_get() panic: remove CONFIG_PANIC_ON_OOPS_VALUE ocfs2: fix double free in user_cluster_connect() checkpatch: suppress strscpy warnings for userspace tools cramfs: fix incorrect physical page address calculation kernel: prevent prctl(PR_SET_PDEATHSIG) from racing with parent process exit Squashfs: fix uninit-value in squashfs_get_parent kho: only fill kimage if KHO is finalized ocfs2: avoid extra calls to strlen() after ocfs2_sprintf_system_inode_name() kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock coccinelle: platform_no_drv_owner: handle also built-in drivers coccinelle: of_table: handle SPI device ID tables lib/decompress: use designated initializers for struct compress_format efi: support booting with kexec handover (KHO) ...

fs/proc/base.c: fix the wrong format specifier

2025-09-14T00:32:54+00:00

Use '%d' instead of '%u' for int. Link: https://lkml.kernel.org/r/20250903083948.2536-1-zhangjiao2@cmss.chinamobile.com Signed-off-by: zhang jiao Cc: Al Viro Cc: Christian Brauner Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Lorenzo Stoakes Cc: Thomas Gleinxer Cc: xu xin Signed-off-by: Andrew Morton

mm: convert remaining users to mm_flags_*() accessors

2025-09-13T23:54:58+00:00

As part of the effort to move to mm->flags becoming a bitmap field, convert existing users to making use of the mm_flags_*() accessors which will, when the conversion is complete, be the only means of accessing mm_struct flags. No functional change intended. Link: https://lkml.kernel.org/r/cc67a56f9a8746a8ec7d9791853dc892c1c33e0b.1755012943.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Reviewed-by: Mike Rapoport (Microsoft) Acked-by: David Hildenbrand Cc: Adrian Hunter Cc: Alexander Gordeev Cc: Alexander Shishkin Cc: Al Viro Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Baolin Wang Cc: Barry Song Cc: Ben Segall Cc: Borislav Betkov Cc: Chengming Zhou Cc: Christian Borntraeger Cc: Christian Brauner Cc: David Rientjes Cc: David S. Miller Cc: Dev Jain Cc: Dietmar Eggemann Cc: Gerald Schaefer Cc: Heiko Carstens Cc: "H. Peter Anvin" Cc: Ian Rogers Cc: Ingo Molnar Cc: Jan Kara Cc: Jann Horn Cc: Jason Gunthorpe Cc: Jiri Olsa Cc: John Hubbard Cc: Juri Lelli Cc: Kan Liang Cc: Kees Cook Cc: Marc Rutland Cc: Mariano Pache Cc: "Masami Hiramatsu (Google)" Cc: Mateusz Guzik Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Namhyung kim Cc: Oleg Nesterov Cc: Peter Xu Cc: Peter Zijlstra Cc: Ryan Roberts Cc: Shakeel Butt Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Sven Schnelle Cc: Thomas Gleinxer Cc: Valentin Schneider Cc: Vasily Gorbik Cc: Vincent Guittot Cc: Vlastimil Babka Cc: xu xin Cc: Zi Yan Signed-off-by: Andrew Morton

mm: update coredump logic to correctly use bitmap mm flags

2025-09-13T23:54:57+00:00

The coredump logic is slightly different from other users in that it both stores mm flags and additionally sets and gets using masks. Since the MMF_DUMPABLE_* flags must remain as they are for uABI reasons, and of course these are within the first 32-bits of the flags, it is reasonable to provide access to these in the same fashion so this logic can all still keep working as it has been. Therefore, introduce coredump-specific helpers __mm_flags_get_dumpable() and __mm_flags_set_mask_dumpable() for this purpose, and update all core dump users of mm flags to use these. [lorenzo.stoakes@oracle.com: abstract set_mask_bits() invocation to mm_types.h to satisfy ARC] Link: https://lkml.kernel.org/r/0e7ad263-1ff7-446d-81fe-97cff9c0e7ed@lucifer.local Link: https://lkml.kernel.org/r/2a5075f7e3c5b367d988178c79a3063d12ee53a9.1755012943.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Reviewed-by: Mike Rapoport (Microsoft) Reviewed-by: Christian Brauner Acked-by: David Hildenbrand Cc: Adrian Hunter Cc: Alexander Gordeev Cc: Alexander Shishkin Cc: Al Viro Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Baolin Wang Cc: Barry Song Cc: Ben Segall Cc: Borislav Betkov Cc: Chengming Zhou Cc: Christian Borntraeger Cc: David Rientjes Cc: David S. Miller Cc: Dev Jain Cc: Dietmar Eggemann Cc: Gerald Schaefer Cc: Heiko Carstens Cc: "H. Peter Anvin" Cc: Ian Rogers Cc: Ingo Molnar Cc: Jan Kara Cc: Jann Horn Cc: Jason Gunthorpe Cc: Jiri Olsa Cc: John Hubbard Cc: Juri Lelli Cc: Kan Liang Cc: Kees Cook Cc: Marc Rutland Cc: Mariano Pache Cc: "Masami Hiramatsu (Google)" Cc: Mateusz Guzik Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Michal Hocko Cc: Namhyung kim Cc: Oleg Nesterov Cc: Peter Xu Cc: Peter Zijlstra Cc: Ryan Roberts Cc: Shakeel Butt Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Sven Schnelle Cc: Thomas Gleinxer Cc: Valentin Schneider Cc: Vasily Gorbik Cc: Vincent Guittot Cc: Vlastimil Babka Cc: xu xin Cc: Zi Yan Signed-off-by: Andrew Morton

Merge tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2025-07-29T00:16:12+00:00

Pull hardening updates from Kees Cook: - Introduce and start using TRAILING_OVERLAP() helper for fixing embedded flex array instances (Gustavo A. R. Silva) - mux: Convert mux_control_ops to a flex array member in mux_chip (Thorsten Blum) - string: Group str_has_prefix() and strstarts() (Andy Shevchenko) - Remove KCOV instrumentation from __init and __head (Ritesh Harjani, Kees Cook) - Refactor and rename stackleak feature to support Clang - Add KUnit test for seq_buf API - Fix KUnit fortify test under LTO * tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits) sched/task_stack: Add missing const qualifier to end_of_stack() kstack_erase: Support Clang stack depth tracking kstack_erase: Add -mgeneral-regs-only to silence Clang warnings init.h: Disable sanitizer coverage for __init and __head kstack_erase: Disable kstack_erase for all of arm compressed boot code x86: Handle KCOV __init vs inline mismatches arm64: Handle KCOV __init vs inline mismatches s390: Handle KCOV __init vs inline mismatches arm: Handle KCOV __init vs inline mismatches mips: Handle KCOV __init vs inline mismatch powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON configs/hardening: Enable CONFIG_KSTACK_ERASE stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth stackleak: Rename STACKLEAK to KSTACK_ERASE seq_buf: Introduce KUnit tests string: Group str_has_prefix() and strstarts() kunit/fortify: Add back "volatile" for sizeof() constants acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings ...

stackleak: Rename STACKLEAK to KSTACK_ERASE

2025-07-22T04:35:01+00:00

In preparation for adding Clang sanitizer coverage stack depth tracking that can support stack depth callbacks: - Add the new top-level CONFIG_KSTACK_ERASE option which will be implemented either with the stackleak GCC plugin, or with the Clang stack depth callback support. - Rename CONFIG_GCC_PLUGIN_STACKLEAK as needed to CONFIG_KSTACK_ERASE, but keep it for anything specific to the GCC plugin itself. - Rename all exposed "STACKLEAK" names and files to "KSTACK_ERASE" (named for what it does rather than what it protects against), but leave as many of the internals alone as possible to avoid even more churn. While here, also split "prev_lowest_stack" into CONFIG_KSTACK_ERASE_METRICS, since that's the only place it is referenced from. Suggested-by: Ingo Molnar Link: https://lore.kernel.org/r/20250717232519.2984886-1-kees@kernel.org Signed-off-by: Kees Cook