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| author | Steven Rostedt <srostedt@redhat.com> | 2012-02-20 20:37:32 -0500 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2012-02-21 11:08:13 -0500 |
| commit | 5b34926114e39e12005031269613d2b13194aeba (patch) | |
| tree | 40c0fd479d6e048ceec060d05e141de0a941b7b5 /kernel/trace | |
| parent | e404b321dbb2d6e438522b7dce9c1d0c6a8c5275 (diff) | |
| download | linux-5b34926114e39e12005031269613d2b13194aeba.tar.gz | |
tracing: Don't use p->len field to determine output in __print_*() functions
If more than one __print_*() function is used in a tracepoint (__print_flags(), __print_symbols(), etc), then the temp seq buffer will not be zero on entry. Using the temp seq buffer's length to know if data has been printed or not in the current function is incorrect and may produce incorrect results. Currently, no in-tree tracepoint causes this bug, but new ones may be created. Cc: Andrew Vagin <avagin@openvz.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace_output.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 3efd718984fb..c5a01873567d 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -319,7 +319,7 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim, /* check for left over flags */ if (flags) { - if (p->len && delim) + if (!first && delim) trace_seq_puts(p, delim); trace_seq_printf(p, "0x%lx", flags); } @@ -346,7 +346,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, break; } - if (!p->len) + if (ret == (const char *)(p->buffer + p->len)) trace_seq_printf(p, "0x%lx", val); trace_seq_putc(p, 0); @@ -372,7 +372,7 @@ ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, break; } - if (!p->len) + if (ret == (const char *)(p->buffer + p->len)) trace_seq_printf(p, "0x%llx", val); trace_seq_putc(p, 0); |