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| author | Petr Mladek <pmladek@suse.com> | 2023-01-17 17:10:31 +0100 |
|---|---|---|
| committer | Petr Mladek <pmladek@suse.com> | 2023-01-18 10:13:50 +0100 |
| commit | d551afc25878924991a4c65299dfa83df1cb9ef8 (patch) | |
| tree | 69bc16bf0230786d682ab264b8ae56ae373b7751 /kernel/printk | |
| parent | b0975c47c2178e35038b12ad63f17c64bb522684 (diff) | |
| download | linux-d551afc25878924991a4c65299dfa83df1cb9ef8.tar.gz linux-d551afc25878924991a4c65299dfa83df1cb9ef8.tar.bz2 linux-d551afc25878924991a4c65299dfa83df1cb9ef8.zip | |
printk: Use scnprintf() to print the message about the dropped messages on a console
Use scnprintf() for printing the message about dropped messages on
a console. It returns the really written length of the message.
It prevents potential buffer overflow when the returned length is
later used to copy the buffer content.
Note that the previous code was safe because the scratch buffer was
big enough and the message always fit in. But scnprintf() makes
it more safe, definitely.
Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1530570 ("Memory - corruptions")
Fixes: c4fcc617e148 ("printk: introduce console_prepend_dropped() for dropped messages")
Link: https://lore.kernel.org/r/202301131544.D9E804CCD@keescook
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20230117161031.15499-1-pmladek@suse.com
Diffstat (limited to 'kernel/printk')
| -rw-r--r-- | kernel/printk/printk.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 55338bfd3b55..a9b7dade0d2e 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2716,7 +2716,7 @@ static void console_prepend_dropped(struct printk_message *pmsg, unsigned long d char *outbuf = &pbufs->outbuf[0]; size_t len; - len = snprintf(scratchbuf, scratchbuf_sz, + len = scnprintf(scratchbuf, scratchbuf_sz, "** %lu printk messages dropped **\n", dropped); /* |