Commit-ID: 575570f02761bd680ba5731c1dfd4701062e7fb2 Gitweb: http://git.kernel.org/tip/575570f02761bd680ba5731c1dfd4701062e7fb2 Author: Shaohua Li <shaohua.li@xxxxxxxxx> AuthorDate: Tue, 27 Jul 2010 16:06:34 +0800 Committer: Steven Rostedt <rostedt@xxxxxxxxxxx> CommitDate: Fri, 6 Aug 2010 12:19:15 -0400 tracing: Fix an unallocated memory access in function_graph With CONFIG_DEBUG_PAGEALLOC, I observed an unallocated memory access in function_graph trace. It appears we find a small size entry in ring buffer, but we access it as a big size entry. The access overflows the page size and touches an unallocated page. Cc: <stable@xxxxxxxxxx> Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> LKML-Reference: <1280217994.32400.76.camel@xxxxxxxxxxxxxxxxxxxxxxx> [ Added a comment to explain the problem - SDR ] Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> --- kernel/trace/trace_functions_graph.c | 10 +++++++++- 1 files changed, 9 insertions(+), 1 deletions(-) diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 79f4bac..b4c179a 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -507,7 +507,15 @@ get_return_for_leaf(struct trace_iterator *iter, * if the output fails. */ data->ent = *curr; - data->ret = *next; + /* + * If the next event is not a return type, then + * we only care about what type it is. Otherwise we can + * safely copy the entire event. + */ + if (next->ent.type == TRACE_GRAPH_RET) + data->ret = *next; + else + data->ret.ent.type = next->ent.type; } } -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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