__setup() handlers should return 1 if the parameter is handled.
Returning 0 causes the entire string to be added to init's
environment strings (limited to 32 strings), unnecessarily polluting it.
Using the documented string "evm=fix" causes an Unknown parameter message:
Unknown kernel command line parameters
"BOOT_IMAGE=/boot/bzImage-517rc5 evm=fix", will be passed to user space.
and that string is added to init's environment string space:
Run /sbin/init as init process
with arguments:
/sbin/init
with environment:
HOME=/
TERM=linux
BOOT_IMAGE=/boot/bzImage-517rc5
evm=fix
With this change, using "evm=fix" acts as expected and an invalid
option ("evm=evm") causes a warning to be printed:
evm: invalid "evm" mode
but init's environment is not polluted with this string, as expected.
Fixes:
7102ebcd65c1 ("evm: permit only valid security.evm xattrs to be updated")
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
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
else
pr_err("invalid \"%s\" mode", str);
- return 0;
+ return 1;
}
__setup("evm=", evm_set_fixmode);