From 1507b7a30ad284a2a136ee79c214c0e86c62da64 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 2 Apr 2020 18:17:50 -0500 Subject: [PATCH] exec: Rename the flag called_exec_mmap point_of_no_return Update the comments and make the code easier to understand by renaming this flag. Reviewed-by: Kees Cook Reviewed-by: Greg Ungerer Signed-off-by: "Eric W. Biederman" --- fs/exec.c | 12 ++++++------ include/linux/binfmts.h | 6 +++--- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 6bd82a0..71de9f5 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1326,12 +1326,12 @@ int flush_old_exec(struct linux_binprm * bprm) goto out; /* - * After setting bprm->called_exec_mmap (to mark that current is - * using the prepared mm now), we have nothing left of the original - * process. If anything from here on returns an error, the check - * in search_binary_handler() will SEGV current. + * With the new mm installed it is completely impossible to + * fail and return to the original process. If anything from + * here on returns an error, the check in + * search_binary_handler() will SEGV current. */ - bprm->called_exec_mmap = 1; + bprm->point_of_no_return = true; bprm->mm = NULL; #ifdef CONFIG_POSIX_TIMERS @@ -1720,7 +1720,7 @@ int search_binary_handler(struct linux_binprm *bprm) read_lock(&binfmt_lock); put_binfmt(fmt); - if (retval < 0 && bprm->called_exec_mmap) { + if (retval < 0 && bprm->point_of_no_return) { /* we got to flush_old_exec() and failed after it */ read_unlock(&binfmt_lock); force_sigsegv(SIGSEGV); diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h index 6f564b9..8f479da 100644 --- a/include/linux/binfmts.h +++ b/include/linux/binfmts.h @@ -46,10 +46,10 @@ struct linux_binprm { */ secureexec:1, /* - * Set by flush_old_exec, when exec_mmap has been called. - * This is past the point of no return. + * Set when errors can no longer be returned to the + * original userspace. */ - called_exec_mmap:1; + point_of_no_return:1; #ifdef __alpha__ unsigned int taso:1; #endif -- 2.7.4