iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

tracing/histogram: Fix check for missing operands in an expression

Browse Source 
If a binary operation is detected while parsing an expression string,
the operand strings are deduced by splitting the experssion string at
the position of the detected binary operator. Both operand strings are
sub-strings (can be empty string) of the expression string but will
never be NULL.

Currently a NULL check is used for missing operands, fix this by
checking for empty strings instead.

Link: https://lkml.kernel.org/r/20211112191324.1302505-1-kaleshsingh@google.com

Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Fixes: 9710b2f341a0 ("tracing: Fix operator precedence for hist triggers expression")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Kalesh Singh 2021-11-12 11:13:24 -08:00 committed by Steven Rostedt (VMware)
parent 63f84ae6b8
commit 1cab6bce42
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
kernel/trace/trace_events_hist.c
View File

@ -2581,7 +2581,8 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
operand1_str = str;
str = sep+1;
if (!operand1_str || !str)
/* Binary operator requires both operands */
if (*operand1_str == '\0' || *str == '\0')
goto free;
operand_flags = 0;