lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 17 Nov 2014 14:11:08 -0500 From: Steven Rostedt <rostedt@...dmis.org> To: linux-kernel@...r.kernel.org Cc: Ingo Molnar <mingo@...nel.org>, Andrew Morton <akpm@...ux-foundation.org>, Jiri Kosina <jkosina@...e.cz>, Petr Mladek <pmladek@...e.cz> Subject: [PATCH 1/2] tracing: Clean up tracing_fill_pipe_page() > > I don't like the fact that I did a code structure change with this > patch. This patch should be just a simple conversion of len to > seq_buf_used(). I'm going to strip this change out and put it before > this patch. The function tracing_fill_pipe_page() logic is a little confusing with the use of count saving the seq.len and reusing it. Instead of subtracting a number that is calculated from the saved value of the seq.len from seq.len, just save the seq.len at the start and if we need to reset it, just assign it again. When the seq_buf overflow is len == size + 1, the current logic will break. Changing it to use a saved length for resetting back to the original value is more robust and will work when we change the way seq_buf sets the overflow. Signed-off-by: Steven Rostedt <rostedt@...dmis.org> --- kernel/trace/trace.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 7d7a07e9b9e9..2dbc18e5f929 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4575,23 +4575,37 @@ static size_t tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) { size_t count; + int save_len; int ret; /* Seq buffer is page-sized, exactly what we need. */ for (;;) { - count = iter->seq.seq.len; + save_len = iter->seq.seq.len; ret = print_trace_line(iter); - count = iter->seq.seq.len - count; - if (rem < count) { - rem = 0; - iter->seq.seq.len -= count; + + if (trace_seq_has_overflowed(&iter->seq)) { + iter->seq.seq.len = save_len; break; } + + /* + * This should not be hit, because it should only + * be set if the iter->seq overflowed. But check it + * anyway to be safe. + */ if (ret == TRACE_TYPE_PARTIAL_LINE) { - iter->seq.seq.len -= count; + iter->seq.seq.len = save_len; break; } + count = iter->seq.seq.len - save_len; + if (rem < count) { + rem = 0; + iter->seq.seq.len = save_len; + break; + } + + if (ret != TRACE_TYPE_NO_CONSUME) trace_consume(iter); rem -= count; -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists