stuartl/linux-stable
1
0
Fork 0
mirror of https://kernel.googlesource.com/pub/scm/linux/kernel/git/stable/linux-stable.git synced 2025-09-13 11:07:46 +10:00
Code Issues Releases Wiki Activity

module: Restore the moduleparam prefix length check

Browse Source 
[ Upstream commit bdc877ba6b ]

The moduleparam code allows modules to provide their own definition of
MODULE_PARAM_PREFIX, instead of using the default KBUILD_MODNAME ".".

Commit 730b69d225 ("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 58f86cc89c ("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 9774a1f54f ("[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 58f86cc89c.

Fixes: 58f86cc89c ("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>
This commit is contained in:
Petr Pavlu 2025-06-30 16:32:34 +02:00 committed by Greg Kroah-Hartman
parent 69e83e5527
commit 0b973c5eee
1 changed files with 2 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
include/linux/moduleparam.h
View File

@ -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") \