diff options
| author | Jordan Rome <linux@jordanrome.com> | 2025-02-13 07:21:23 -0800 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2025-02-19 16:57:16 -0800 |
| commit | f0b79944e6f41b1a242b128fb2702378eb48fbd2 (patch) | |
| tree | 1e1edf60a093c9a1fc424a24f64ad1610936dea7 /include/linux/mm.h | |
| parent | ac13c5087299e7690848302cd3073a37c7222364 (diff) | |
mm: Add copy_remote_vm_str() for readng C strings from remote VM
Similar to `access_process_vm()` but specific to strings. Also chunks
reads by page and utilizes `strscpy()` for handling null termination.
The primary motivation for this change is to copy strings from
a non-current task/process in BPF. There is already a helper
`bpf_copy_from_user_task()`, which uses `access_process_vm()` but one to
handle strings would be very helpful.
Signed-off-by: Jordan Rome <linux@jordanrome.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Link: https://lore.kernel.org/bpf/20250213152125.1837400-1-linux@jordanrome.com
Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 7b1068ddcbb7..5409c7b50509 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2486,6 +2486,11 @@ extern int access_process_vm(struct task_struct *tsk, unsigned long addr, extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, void *buf, int len, unsigned int gup_flags); +#ifdef CONFIG_BPF_SYSCALL +extern int copy_remote_vm_str(struct task_struct *tsk, unsigned long addr, + void *buf, int len, unsigned int gup_flags); +#endif + long get_user_pages_remote(struct mm_struct *mm, unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, |