| Message ID | 20220222005817.11087-1-rdunlap@infradead.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] mm/memcontrol: return 1 from cgroup.memory __setup() handler | expand |
--- linux-next-20220217.orig/mm/mmap.c +++ linux-next-20220217/mm/mmap.c @@ -2557,7 +2557,7 @@ static int __init cmdline_parse_stack_gu if (!*endptr) stack_guard_gap = val << PAGE_SHIFT; - return 0; + return 1; } __setup("stack_guard_gap=", cmdline_parse_stack_guard_gap);
__setup() handlers should return 1 if the command line option is handled and 0 if not (or maybe never return 0; it just pollutes init's environment). This prevents: Unknown kernel command line parameters \ "BOOT_IMAGE=/boot/bzImage-517rc5 stack_guard_gap=100", will be \ passed to user space. Run /sbin/init as init process with arguments: /sbin/init with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc5 stack_guard_gap=100 Return 1 to indicate that the boot option has been handled. Note that there is no warning message if someone enters: stack_guard_gap=anything_invalid and 'val' and stack_guard_gap are both set to 0 due to the use of simple_strtoul(). This could be improved by using kstrtoxxx() and checking for an error. It appears that having stack_guard_gap == 0 is valid (if unexpected) since using "stack_guard_gap=0" on the kernel command line does that. Fixes: 1be7107fbe18e ("mm: larger stack guard gap, between vmas") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com> --- mm/mmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)