From 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 2 Sep 2026 15:31:14 -0700 Subject: treewide: refresh kmalloc_obj() conversions This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook --- lib/once.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) create mode 100644 lib/once.c (limited to 'lib/once.c') diff --git a/lib/once.c b/lib/once.c new file mode 100644 index 000000000..0a0a91915 --- /dev/null +++ b/lib/once.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +struct once_work { + struct work_struct work; + struct static_key_true *key; + struct module *module; +}; + +static void once_deferred(struct work_struct *w) +{ + struct once_work *work; + + work = container_of(w, struct once_work, work); + BUG_ON(!static_key_enabled(work->key)); + static_branch_disable(work->key); + module_put(work->module); + kfree(work); +} + +static void once_disable_jump(struct static_key_true *key, struct module *mod) +{ + struct once_work *w; + + w = kmalloc_obj(*w, GFP_ATOMIC); + if (!w) + return; + + INIT_WORK(&w->work, once_deferred); + w->key = key; + w->module = mod; + __module_get(mod); + schedule_work(&w->work); +} + +static DEFINE_SPINLOCK(once_lock); + +bool __do_once_start(bool *done, unsigned long *flags) + __acquires(once_lock) +{ + spin_lock_irqsave(&once_lock, *flags); + if (*done) { + spin_unlock_irqrestore(&once_lock, *flags); + /* Keep sparse happy by restoring an even lock count on + * this lock. In case we return here, we don't call into + * __do_once_done but return early in the DO_ONCE() macro. + */ + __acquire(once_lock); + return false; + } + + return true; +} +EXPORT_SYMBOL(__do_once_start); + +void __do_once_done(bool *done, struct static_key_true *once_key, + unsigned long *flags, struct module *mod) + __releases(once_lock) +{ + *done = true; + spin_unlock_irqrestore(&once_lock, *flags); + once_disable_jump(once_key, mod); +} +EXPORT_SYMBOL(__do_once_done); + +static DEFINE_MUTEX(once_mutex); + +bool __do_once_sleepable_start(bool *done) + __acquires(once_mutex) +{ + mutex_lock(&once_mutex); + if (*done) { + mutex_unlock(&once_mutex); + /* Keep sparse happy by restoring an even lock count on + * this mutex. In case we return here, we don't call into + * __do_once_done but return early in the DO_ONCE_SLEEPABLE() macro. + */ + __acquire(once_mutex); + return false; + } + + return true; +} +EXPORT_SYMBOL(__do_once_sleepable_start); + +void __do_once_sleepable_done(bool *done, struct static_key_true *once_key, + struct module *mod) + __releases(once_mutex) +{ + *done = true; + mutex_unlock(&once_mutex); + once_disable_jump(once_key, mod); +} +EXPORT_SYMBOL(__do_once_sleepable_done); -- cgit v1.3.1