From: Thomas Gleixner Date: Thu, 10 Dec 2009 22:46:52 +0000 (+0100) Subject: tracing: Fix wrong usage of strstrip in trace_ksyms X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d954fbf0ff6b5fdfb32350e85a2f15d3db976506;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git tracing: Fix wrong usage of strstrip in trace_ksyms strstrip returns a pointer to the first non space character, but the code in parse_ksym_trace_str() ignores that. strstrip is now must_check and therefor we get the correct warning: kernel/trace/trace_ksym.c:294: warning: ignoring return value of ‘strstrip’, declared with attribute warn_unused_result We are really not interested in leading whitespace here. Fix that and cleanup the dozen kfree() exit pathes. Signed-off-by: Thomas Gleixner Cc: Xiao Guangrong Cc: Steven Rostedt --- diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c index ddfa0fd43bc0..64e7a5bd6692 100644 --- a/kernel/trace/trace_ksym.c +++ b/kernel/trace/trace_ksym.c @@ -277,21 +277,20 @@ static ssize_t ksym_trace_filter_write(struct file *file, { struct trace_ksym *entry; struct hlist_node *node; - char *input_string, *ksymname = NULL; + char *buf, *input_string, *ksymname = NULL; unsigned long ksym_addr = 0; int ret, op, changed = 0; - input_string = kzalloc(count + 1, GFP_KERNEL); - if (!input_string) + buf = kzalloc(count + 1, GFP_KERNEL); + if (!buf) return -ENOMEM; - if (copy_from_user(input_string, buffer, count)) { - kfree(input_string); - return -EFAULT; - } - input_string[count] = '\0'; + ret = -EFAULT; + if (copy_from_user(buf, buffer, count)) + goto out; - strstrip(input_string); + buf[count] = '\0'; + input_string = strstrip(buf); /* * Clear all breakpoints if: @@ -302,15 +301,13 @@ static ssize_t ksym_trace_filter_write(struct file *file, if (!input_string[0] || !strcmp(input_string, "0") || !strcmp(input_string, "*:---")) { __ksym_trace_reset(); - kfree(input_string); - return count; + ret = 0; + goto out; } ret = op = parse_ksym_trace_str(input_string, &ksymname, &ksym_addr); - if (ret < 0) { - kfree(input_string); - return ret; - } + if (ret < 0) + goto out; mutex_lock(&ksym_tracer_mutex); @@ -321,7 +318,7 @@ static ssize_t ksym_trace_filter_write(struct file *file, if (entry->attr.bp_type != op) changed = 1; else - goto out; + goto out_unlock; break; } } @@ -336,28 +333,24 @@ static ssize_t ksym_trace_filter_write(struct file *file, if (IS_ERR(entry->ksym_hbp)) ret = PTR_ERR(entry->ksym_hbp); else - goto out; + goto out_unlock; } /* Error or "symbol:---" case: drop it */ ksym_filter_entry_count--; hlist_del_rcu(&(entry->ksym_hlist)); synchronize_rcu(); kfree(entry); - goto out; + goto out_unlock; } else { /* Check for malformed request: (4) */ - if (op == 0) - goto out; - ret = process_new_ksym_entry(ksymname, op, ksym_addr); + if (op) + ret = process_new_ksym_entry(ksymname, op, ksym_addr); } -out: +out_unlock: mutex_unlock(&ksym_tracer_mutex); - - kfree(input_string); - - if (!ret) - ret = count; - return ret; +out: + kfree(buf); + return !ret ? count : ret; } static const struct file_operations ksym_tracing_fops = {