diff options
| author | Mike Rapoport (Microsoft) <rppt@kernel.org> | 2025-07-13 10:17:24 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-08-02 12:06:11 -0700 |
| commit | 838955f64ae7582f009a3538889bb9244f37ab26 (patch) | |
| tree | 20177dbe146ad7ca56529b42c90d25c750c22bdd /mm/execmem.c | |
| parent | fcd90ad31e29d0b403f3a074a64cd7f0876175dd (diff) | |
| download | tip-838955f64ae7582f009a3538889bb9244f37ab26.tar.gz | |
execmem: introduce execmem_alloc_rw()
Some callers of execmem_alloc() require the memory to be temporarily
writable even when it is allocated from ROX cache. These callers use
execemem_make_temp_rw() right after the call to execmem_alloc().
Wrap this sequence in execmem_alloc_rw() API.
Link: https://lkml.kernel.org/r/20250713071730.4117334-3-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/execmem.c')
| -rw-r--r-- | mm/execmem.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/mm/execmem.c b/mm/execmem.c index aac211bc88c570..d0bf0123bce4c4 100644 --- a/mm/execmem.c +++ b/mm/execmem.c @@ -336,7 +336,7 @@ static bool execmem_cache_free(void *ptr) return true; } -int execmem_make_temp_rw(void *ptr, size_t size) +static int execmem_force_rw(void *ptr, size_t size) { unsigned int nr = PAGE_ALIGN(size) >> PAGE_SHIFT; unsigned long addr = (unsigned long)ptr; @@ -358,6 +358,16 @@ int execmem_restore_rox(void *ptr, size_t size) } #else /* CONFIG_ARCH_HAS_EXECMEM_ROX */ +/* + * when ROX cache is not used the permissions defined by architectures for + * execmem ranges that are updated before use (e.g. EXECMEM_MODULE_TEXT) must + * be writable anyway + */ +static inline int execmem_force_rw(void *ptr, size_t size) +{ + return 0; +} + static void *execmem_cache_alloc(struct execmem_range *range, size_t size) { return NULL; @@ -387,6 +397,21 @@ void *execmem_alloc(enum execmem_type type, size_t size) return kasan_reset_tag(p); } +void *execmem_alloc_rw(enum execmem_type type, size_t size) +{ + void *p __free(execmem) = execmem_alloc(type, size); + int err; + + if (!p) + return NULL; + + err = execmem_force_rw(p, size); + if (err) + return NULL; + + return no_free_ptr(p); +} + void execmem_free(void *ptr) { /* |