strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. There is a _nearly_ identical implementation of fill_psinfo present in binfmt_elf.c -- except that one uses get_task_comm over strncpy(). Let's mirror that in binfmt_elf_fdpic.c Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@xxxxxxxxxxxxxxx Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx> --- Changes in v2: - use get_task_comm (thanks Eric) - Link to v1: https://lore.kernel.org/r/20240321-strncpy-fs-binfmt_elf_fdpic-c-v1-1-fdde26c8989e@xxxxxxxxxx --- Note: build-tested only. Found with: $ rg "strncpy\(" --- fs/binfmt_elf_fdpic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c index 1920ed69279b..3314249e8674 100644 --- a/fs/binfmt_elf_fdpic.c +++ b/fs/binfmt_elf_fdpic.c @@ -1359,7 +1359,7 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid)); SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid)); rcu_read_unlock(); - strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); + get_task_comm(psinfo->pr_fname, p); return 0; } --- base-commit: a4145ce1e7bc247fd6f2846e8699473448717b37 change-id: 20240320-strncpy-fs-binfmt_elf_fdpic-c-828286d76310 Best regards, -- Justin Stitt <justinstitt@xxxxxxxxxx>
