Commit 077a1cc0 authored by Nikitas Angelinas's avatar Nikitas Angelinas Committed by Petr Mladek
Browse files

printk: Clean up do_syslog() error handling

The error variable in do_syslog() is preemptively set to the error code
before the error condition is checked, and then set to 0 if the error
condition is not encountered. This is not necessary, as it is likely
simpler to return immediately upon encountering the error condition. A
redundant set of the error variable to 0 is also removed.

This patch has been build-tested on x86_64, but not tested for
functionality.

Link: http://lkml.kernel.org/r/20170730033636.GA935@vostro


Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: default avatarNikitas Angelinas <nikitas.angelinas@gmail.com>
Reviewed-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
parent 5a814231
......@@ -1435,7 +1435,7 @@ int do_syslog(int type, char __user *buf, int len, int source)
error = check_syslog_permissions(type, source);
if (error)
goto out;
return error;
switch (type) {
case SYSLOG_ACTION_CLOSE: /* Close log */
......@@ -1443,20 +1443,16 @@ int do_syslog(int type, char __user *buf, int len, int source)
case SYSLOG_ACTION_OPEN: /* Open log */
break;
case SYSLOG_ACTION_READ: /* Read from log */
error = -EINVAL;
if (!buf || len < 0)
goto out;
error = 0;
return -EINVAL;
if (!len)
goto out;
if (!access_ok(VERIFY_WRITE, buf, len)) {
error = -EFAULT;
goto out;
}
return 0;
if (!access_ok(VERIFY_WRITE, buf, len))
return -EFAULT;
error = wait_event_interruptible(log_wait,
syslog_seq != log_next_seq);
if (error)
goto out;
return error;
error = syslog_print(buf, len);
break;
/* Read/clear last kernel messages */
......@@ -1465,16 +1461,12 @@ int do_syslog(int type, char __user *buf, int len, int source)
/* FALL THRU */
/* Read last kernel messages */
case SYSLOG_ACTION_READ_ALL:
error = -EINVAL;
if (!buf || len < 0)
goto out;
error = 0;
return -EINVAL;
if (!len)
goto out;
if (!access_ok(VERIFY_WRITE, buf, len)) {
error = -EFAULT;
goto out;
}
return 0;
if (!access_ok(VERIFY_WRITE, buf, len))
return -EFAULT;
error = syslog_print_all(buf, len, clear);
break;
/* Clear ring buffer */
......@@ -1496,15 +1488,13 @@ int do_syslog(int type, char __user *buf, int len, int source)
break;
/* Set level of messages printed to console */
case SYSLOG_ACTION_CONSOLE_LEVEL:
error = -EINVAL;
if (len < 1 || len > 8)
goto out;
return -EINVAL;
if (len < minimum_console_loglevel)
len = minimum_console_loglevel;
console_loglevel = len;
/* Implicitly re-enable logging to console */
saved_console_loglevel = LOGLEVEL_DEFAULT;
error = 0;
break;
/* Number of chars in the log buffer */
case SYSLOG_ACTION_SIZE_UNREAD:
......@@ -1526,7 +1516,6 @@ int do_syslog(int type, char __user *buf, int len, int source)
u64 seq = syslog_seq;
u32 idx = syslog_idx;
error = 0;
while (seq < log_next_seq) {
struct printk_log *msg = log_from_idx(idx);
......@@ -1546,7 +1535,7 @@ int do_syslog(int type, char __user *buf, int len, int source)
error = -EINVAL;
break;
}
out:
return error;
}
......
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