On Fri, Apr 14, 2023 at 06:50:59PM +0200, Markus Elfring wrote: > >> The address of a data structure member was determined before > >> a corresponding null pointer check in the implementation of > >> the function “nd_pfn_validate”. > >> > >> Thus avoid the risk for undefined behaviour by replacing the usage of > >> the local variable “parent_uuid” by a direct function call within > >> a later condition check. > > > > Hi Markus, > > > > I think I understand what you are saying above, but I don't follow > > how that applies here. This change seems to be a nice simplification, > > parent_uuid, is used once, just grab it when needed. > > Thanks for your positive feedback. Hi Markus, FYI - I'm a tiny bit taken aback that in response to me applying, and providing feedback, on your patch, you respond with 2 links for me to follow and cut off a chunk of my feedback. Seems like it would taken the same amount of time to just answer my two questions directly. Was this part of a larger patch set? Andy's comment seems to indicate that. Would have been nice to be CC'd on the cover letter. More below... > > > > What is the risk of undefined behavior? > > See also: > https://wiki.sei.cmu.edu/confluence/display/c/EXP34-C.+Do+not+dereference+null+pointers?focusedCommentId=405504137#comment-405504137 Where is the NULL pointer dereference here? > > > >> This issue was detected by using the Coccinelle software. > > Which cocci script? > > See also: > Reconsidering pointer dereferences before null pointer checks (with SmPL) > https://lore.kernel.org/cocci/1a11455f-ab57-dce0-1677-6beb8492a257@xxxxxx/ > https://sympa.inria.fr/sympa/arc/cocci/2023-04/msg00021.html > The cocci script linked above does not seem to apply here. > > How do you think about to review and improve any similarly affected software components? > > Regards, > Markus >
