tracing: Reject string operand in the histogram expression

commit a9d10ca4986571bffc19778742d508cc8dd13e02 upstream.

Since the string type can not be the target of the addition / subtraction
operation, it must be rejected. Without this fix, the string type silently
converted to digits.

Link: https://lkml.kernel.org/r/162742654278.290973.1523000673366456634.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: 100719dcef ("tracing: Add simple expression support to hist triggers")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Masami Hiramatsu 2021-07-28 07:55:43 +09:00 committed by Greg Kroah-Hartman
parent b10ccc2c58
commit b2aca8daa5

View File

@ -65,7 +65,8 @@
C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \
C(EMPTY_SORT_FIELD, "Empty sort field"), \
C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \
C(INVALID_SORT_FIELD, "Sort field must be a key or a val"),
C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \
C(INVALID_STR_OPERAND, "String type can not be an operand in expression"),
#undef C
#define C(a, b) HIST_ERR_##a
@ -2140,6 +2141,13 @@ static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
ret = PTR_ERR(operand1);
goto free;
}
if (operand1->flags & HIST_FIELD_FL_STRING) {
/* String type can not be the operand of unary operator. */
hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
destroy_hist_field(operand1, 0);
ret = -EINVAL;
goto free;
}
expr->flags |= operand1->flags &
(HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
@ -2241,6 +2249,11 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
operand1 = NULL;
goto free;
}
if (operand1->flags & HIST_FIELD_FL_STRING) {
hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str));
ret = -EINVAL;
goto free;
}
/* rest of string could be another expression e.g. b+c in a+b+c */
operand_flags = 0;
@ -2250,6 +2263,11 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
operand2 = NULL;
goto free;
}
if (operand2->flags & HIST_FIELD_FL_STRING) {
hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
ret = -EINVAL;
goto free;
}
ret = check_expr_operands(file->tr, operand1, operand2);
if (ret)