Btrfs: avoid buffer overrun in btrfs_printk

The buffer read-overrun would be triggered by a printk format
starting with <N>, where N is a single digit.  NUL-terminate
after strncpy.  Use memcpy, not strncpy, since we know the
string we're copying fits in the destination buffer and
contains no NUL byte.

Signed-off-by: Jim Meyering <meyering@redhat.com>
This commit is contained in:
Jim Meyering 2012-04-26 18:35:12 +02:00 committed by Josef Bacik
parent 2eec6c8102
commit f07c9a79f0

View file

@ -188,7 +188,8 @@ void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...)
va_start(args, fmt);
if (fmt[0] == '<' && isdigit(fmt[1]) && fmt[2] == '>') {
strncpy(lvl, fmt, 3);
memcpy(lvl, fmt, 3);
lvl[3] = '\0';
fmt += 3;
type = logtypes[fmt[1] - '0'];
} else