diff options
author | Petr Mladek <pmladek@suse.cz> | 2014-04-03 14:48:41 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-03 16:21:07 -0700 |
commit | e8c42d36ab86cf45f88c3a0e344233b1032fbf3d (patch) | |
tree | 94fe60e04065bb06c1c83c68b8371dedc113cfc3 | |
parent | c64730b26f08cccfbc8fcbf169c304b4bd71dcac (diff) | |
download | linux-e8c42d36ab86cf45f88c3a0e344233b1032fbf3d.tar.bz2 |
printk: add comment about tricky check for text buffer size
There is no check for potential "text_len" overflow. It is not needed
because only valid level is detected. It took me some time to
understand why. It would deserve a comment ;-)
Signed-off-by: Petr Mladek <pmladek@suse.cz>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | kernel/printk/printk.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index db7a02e05241..012f3e40671d 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -1561,6 +1561,11 @@ asmlinkage int vprintk_emit(int facility, int level, case 'd': /* KERN_DEFAULT */ lflags |= LOG_PREFIX; } + /* + * No need to check length here because vscnprintf + * put '\0' at the end of the string. Only valid and + * newly printed level is detected. + */ text_len -= end_of_header - text; text = (char *)end_of_header; } |