Bug #7591 In-place update of NULL fields leads to crashes

• Submitted: 30 Dec 2004 16:59
• Modified: 30 Dec 2004 17:51
• Reporter: Marko Mäkelä
• Status: Closed
• Category: MySQL Server: InnoDB storage engine
• Severity: S1 (Critical)
• Version: 5.0.3-bk
• OS: Any (all)
• Assigned to: Marko Mäkelä
• CPU Architecture: Any

[30 Dec 2004 16:59] Marko Mäkelä

Description:
An in-place update of a previously NULL field to a non-NULL value leads to dereferencing a null pointer in rec_set_nth_field().

How to repeat:
Create a table with a fixed-size nullable column. Insert a NULL value into the column. Update it to non-NULL. (I didn't use this exact procedure, but I think this should lead to the crash as well.)

Suggested fix:
Remove the assignment "field = NULL" in rec_get_nth_field().

[30 Dec 2004 17:51] Marko Mäkelä

Fixed in source repository.