Found another buffer overflow in this code that was introduced by e3756477aec028427fec767957c0d4b6cfb87208 trying to solve a related overflow. strace still shows a problem: syslog(0x3, 0x7fffd65375d0, 0x1000) = 4107 The first record output was in the middle of a LOG_CONT line: <4>[ 2.974999] 0x0000000000000500-0x000000000000052f SystemIO conflicts with Region \GPIO 1 (20130328/utaddress-251) This happens because when discarding records to be less than len, every line it subtracts should be the first line which means prev should be 0. Otherwise for example it won't include the prefix len if the last line was a LOG_CONT record, which however will be printed because there won't be a previous line. This patch makes sure enough records are discarded to be under len. CC: stable@xxxxxxxxxxxxxxx Signed-off-by: Debabrata Banerjee <dbanerje@xxxxxxxxxx> --- kernel/printk/printk.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index b1d255f..c1722d5 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -1067,7 +1067,6 @@ static int syslog_print_all(char __user *buf, int size, bool clear) struct printk_log *msg = log_from_idx(idx); len -= msg_print_text(msg, prev, true, NULL, 0); - prev = msg->flags; idx = log_next(idx); seq++; } @@ -2780,7 +2779,6 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog, l -= msg_print_text(msg, prev, true, NULL, 0); idx = log_next(idx); seq++; - prev = msg->flags; } /* last message in next interation */ -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html