diff options
author | Petr Pavlu <petr.pavlu@suse.com> | 2025-06-30 16:32:34 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-15 16:39:16 +0200 |
commit | 96ae3d82a929343ca8df2c40d8f4ef20e6ffef62 (patch) | |
tree | 479d729eca5dc72174a1457023cd694378d6e01a | |
parent | b4e37ee42027ed32c0cd1ed492a3019d5ccf5537 (diff) |
module: Restore the moduleparam prefix length check
[ Upstream commit bdc877ba6b7ff1b6d2ebeff11e63da4a50a54854 ]
The moduleparam code allows modules to provide their own definition of
MODULE_PARAM_PREFIX, instead of using the default KBUILD_MODNAME ".".
Commit 730b69d22525 ("module: check kernel param length at compile time,
not runtime") added a check to ensure the prefix doesn't exceed
MODULE_NAME_LEN, as this is what param_sysfs_builtin() expects.
Later, commit 58f86cc89c33 ("VERIFY_OCTAL_PERMISSIONS: stricter checking
for sysfs perms.") removed this check, but there is no indication this was
intentional.
Since the check is still useful for param_sysfs_builtin() to function
properly, reintroduce it in __module_param_call(), but in a modernized form
using static_assert().
While here, clean up the __module_param_call() comments. In particular,
remove the comment "Default value instead of permissions?", which comes
from commit 9774a1f54f17 ("[PATCH] Compile-time check re world-writeable
module params"). This comment was related to the test variable
__param_perm_check_##name, which was removed in the previously mentioned
commit 58f86cc89c33.
Fixes: 58f86cc89c33 ("VERIFY_OCTAL_PERMISSIONS: stricter checking for sysfs perms.")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Link: https://lore.kernel.org/r/20250630143535.267745-4-petr.pavlu@suse.com
Signed-off-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | include/linux/moduleparam.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index bfb85fd13e1f..110e9d09de24 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -282,10 +282,9 @@ struct kparam_array #define __moduleparam_const const #endif -/* This is the fundamental function for registering boot/module - parameters. */ +/* This is the fundamental function for registering boot/module parameters. */ #define __module_param_call(prefix, name, ops, arg, perm, level, flags) \ - /* Default value instead of permissions? */ \ + static_assert(sizeof(""prefix) - 1 <= MAX_PARAM_PREFIX_LEN); \ static const char __param_str_##name[] = prefix #name; \ static struct kernel_param __moduleparam_const __param_##name \ __used __section("__param") \ |