From faf8c714f4508207a9c81cc94dafc76ed6680b44 Mon Sep 17 00:00:00 2001 From: Dave Young Date: Thu, 18 Oct 2007 03:05:07 -0700 Subject: [PATCH] param_sysfs_builtin memchr argument fix If memchr argument is longer than strlen(kp->name), there will be some weird result. It will casuse duplicate filenames in sysfs for the "nousb". kernel warning messages are as bellow: sysfs: duplicate filename 'usbcore' can not be created WARNING: at fs/sysfs/dir.c:416 sysfs_add_one() [] sysfs_add_one+0xa0/0xe0 [] create_dir+0x48/0xb0 [] sysfs_create_dir+0x29/0x50 [] create_dir+0x1b/0x50 [] kobject_add+0x46/0x150 [] kobject_init+0x3a/0x80 [] kernel_param_sysfs_setup+0x50/0xb0 [] param_sysfs_builtin+0xee/0x130 [] param_sysfs_init+0x23/0x60 [] __next_cpu+0x12/0x20 [] kernel_init+0x0/0xb0 [] kernel_init+0x0/0xb0 [] do_initcalls+0x46/0x1e0 [] create_proc_entry+0x52/0x90 [] register_irq_proc+0x9c/0xc0 [] proc_mkdir_mode+0x34/0x50 [] kernel_init+0x0/0xb0 [] kernel_init+0x62/0xb0 [] kernel_thread_helper+0x7/0x14 ======================= kobject_add failed for usbcore with -EEXIST, don't try to register things with the same name in the same directory. [] kobject_add+0xf6/0x150 [] kernel_param_sysfs_setup+0x50/0xb0 [] param_sysfs_builtin+0xee/0x130 [] param_sysfs_init+0x23/0x60 [] __next_cpu+0x12/0x20 [] kernel_init+0x0/0xb0 [] kernel_init+0x0/0xb0 [] do_initcalls+0x46/0x1e0 [] create_proc_entry+0x52/0x90 [] register_irq_proc+0x9c/0xc0 [] proc_mkdir_mode+0x34/0x50 [] kernel_init+0x0/0xb0 [] kernel_init+0x62/0xb0 [] kernel_thread_helper+0x7/0x14 ======================= Module 'usbcore' failed to be added to sysfs, error number -17 The system will be unstable now. Signed-off-by: Dave Young Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/params.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/params.c b/kernel/params.c index 1d6aca288cd..16f269e9ddc 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -592,11 +592,17 @@ static void __init param_sysfs_builtin(void) for (i=0; i < __stop___param - __start___param; i++) { char *dot; + size_t kplen; kp = &__start___param[i]; + kplen = strlen(kp->name); /* We do not handle args without periods. */ - dot = memchr(kp->name, '.', MAX_KBUILD_MODNAME); + if (kplen > MAX_KBUILD_MODNAME) { + DEBUGP("kernel parameter name is too long: %s\n", kp->name); + continue; + } + dot = memchr(kp->name, '.', kplen); if (!dot) { DEBUGP("couldn't find period in %s\n", kp->name); continue; -- 2.20.1