diff options
| author | Petr Pavlu <petr.pavlu@suse.com> | 2025-06-30 16:32:32 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-20 18:41:28 +0200 |
| commit | d1225f017ff14b298b19db7aa0c5d1bc15d1b374 (patch) | |
| tree | e3e0012af80e1edd81bb8305acfc208c96007f4f | |
| parent | fa16caeee84f12379dcd9c5432fb0cc5a6fbfc3f (diff) | |
module: Prevent silent truncation of module name in delete_module(2)
[ Upstream commit a6323bd4e611567913e23df5b58f2d4e4da06789 ]
Passing a module name longer than MODULE_NAME_LEN to the delete_module
syscall results in its silent truncation. This really isn't much of
a problem in practice, but it could theoretically lead to the removal of an
incorrect module. It is more sensible to return ENAMETOOLONG or ENOENT in
such a case.
Update the syscall to return ENOENT, as documented in the delete_module(2)
man page to mean "No module by that name exists." This is appropriate
because a module with a name longer than MODULE_NAME_LEN cannot be loaded
in the first place.
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Link: https://lore.kernel.org/r/20250630143535.267745-2-petr.pavlu@suse.com
Signed-off-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | kernel/module/main.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/kernel/module/main.c b/kernel/module/main.c index 43df45c39f59..b62f9ccc50d6 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -751,14 +751,16 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, struct module *mod; char name[MODULE_NAME_LEN]; char buf[MODULE_FLAGS_BUF_SIZE]; - int ret, forced = 0; + int ret, len, forced = 0; if (!capable(CAP_SYS_MODULE) || modules_disabled) return -EPERM; - if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) - return -EFAULT; - name[MODULE_NAME_LEN-1] = '\0'; + len = strncpy_from_user(name, name_user, MODULE_NAME_LEN); + if (len == 0 || len == MODULE_NAME_LEN) + return -ENOENT; + if (len < 0) + return len; audit_log_kern_module(name); |