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livepatch: Reorder to use before freeing a pointer
authorTom Rix <trix@redhat.com>
Sun, 20 Mar 2022 01:51:43 +0000 (18:51 -0700)
committerPetr Mladek <pmladek@suse.com>
Wed, 23 Mar 2022 12:51:11 +0000 (13:51 +0100)
commit5e6ded2e7a5d9c71186acc8f51989ef6e6addda4
treeb676e714e34b2b6d19084532e2808a450f95759a
parent4327b9eaf8a4ddd2c534e4f4ed7c949cf3d2be1e
livepatch: Reorder to use before freeing a pointer

Clang static analysis reports this issue
livepatch-shadow-fix1.c:113:2: warning: Use of
  memory after it is freed
  pr_info("%s: dummy @ %p, prevented leak @ %p\n",
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The pointer is freed in the previous statement.
Reorder the pr_info to report before the free.

Similar issue in livepatch-shadow-fix2.c

Note that it is a false positive. pr_info() just prints the address.
The freed memory is not accessed. Well, the static analyzer could not
know this easily.

Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: David Vernet <void@manifault.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
[pmladek@suse.com: Note about that it was false positive.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220320015143.2208591-1-trix@redhat.com
samples/livepatch/livepatch-shadow-fix1.c
samples/livepatch/livepatch-shadow-fix2.c