5.4-stable review patch. If anyone has any objections, please let me know.
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From: Petr Pavlu petr.pavlu@suse.com
[ 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 --- include/linux/moduleparam.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index 4d5a851cafe8..6e9062caa7df 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -214,10 +214,9 @@ 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 \