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5.313. strace

Updated strace packages that fix a bug are now available for Red Hat Enterprise Linux 6.
The strace packages provide an utility to intercept and record the system calls called and received by a running process. The strace utility can print a record of each system call, its arguments, and its return value. The strace utility is useful for diagnosing, debugging, and instructional purposes.

Bug Fix

Previously, the strace utility used magic breakpoints in the process startup code to detect and control process startup. Consequently, under certain circumstances, the %ebx register could be corrupted around the clone syscall within the libc_fork() function, which could cause an application to terminate unexpectedly with a segmentation fault while under strace control. This update changes strace to use the TRACE{FORK,VFORK,CLONE} ptrace capabilities which provide a cleaner, less error-prone interface to monitor and control process startup when tracing, thus preventing this bug.
All users of strace are advised to upgrade to these updated packages, which fix this bug.