]> git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/commit
exec: separate MM_ANONPAGES and RLIMIT_STACK accounting
authorOleg Nesterov <oleg@redhat.com>
Thu, 3 Jan 2019 23:28:11 +0000 (15:28 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 4 Jan 2019 21:13:47 +0000 (13:13 -0800)
commit655c16a8ce9c15842547f40ce23fd148aeccc074
tree6008b24bf4add9cd20d479dd53eebbc56ce1fd74
parent8099b047ecc431518b9bb6bdbba3549bbecdc343
exec: separate MM_ANONPAGES and RLIMIT_STACK accounting

get_arg_page() checks bprm->rlim_stack.rlim_cur and re-calculates the
"extra" size for argv/envp pointers every time, this is a bit ugly and
even not strictly correct: acct_arg_size() must not account this size.

Remove all the rlimit code in get_arg_page().  Instead, add bprm->argmin
calculated once at the start of __do_execve_file() and change
copy_strings to check bprm->p >= bprm->argmin.

The patch adds the new helper, prepare_arg_pages() which initializes
bprm->argc/envc and bprm->argmin.

[oleg@redhat.com: fix !CONFIG_MMU version of get_arg_page()]
Link: http://lkml.kernel.org/r/20181126122307.GA1660@redhat.com
[akpm@linux-foundation.org: use max_t]
Link: http://lkml.kernel.org/r/20181112160910.GA28440@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/exec.c
include/linux/binfmts.h