Summary:
Two CSA bug reports where only the uniqueing location is different
should be treated as different problems. The role of uniqueing location
is to differentiate bug reports.
Reviewers: Szelethus, baloghadamsoftware, NoQ, vsavchenko, xazax.hun, martong
Reviewed By: NoQ
Subscribers: NoQ, rnkovacs, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, gamesh411, Charusso, martong, ASDenysPetrov, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D83115
These diagnose overflowing calls to subset of fortifiable functions. Some
functions, like sprintf or strcpy aren't supported right not, but we should
probably support these in the future. We previously supported this kind of
functionality with -Wbuiltin-memcpy-chk-size, but that diagnostic doesn't work
with _FORTIFY implementations that use wrapper functions. Also unlike that
diagnostic, we emit these warnings regardless of whether _FORTIFY_SOURCE is
actually enabled, which is nice for programs that don't enable the runtime
checks.
Why not just use diagnose_if, like Bionic does? We can get better diagnostics in
the compiler (i.e. mention the sizes), and we have the potential to diagnose
sprintf and strcpy which is impossible with diagnose_if (at least, in languages
that don't support C++14 constexpr). This approach also saves standard libraries
from having to add diagnose_if.
rdar://48006655
Differential revision: https://reviews.llvm.org/D58797
llvm-svn: 356397
It's an old bug that consists in stale references to symbols remaining in the
GDM if they disappear from other program state sections as a result of any
operation that isn't the actual dead symbol collection. The most common example
here is:
FILE *fp = fopen("myfile.txt", "w");
fp = 0; // leak of file descriptor
In this example the leak were not detected previously because the symbol
disappears from the public part of the program state due to evaluating
the assignment. For that reason the checker never receives a notification
that the symbol is dead, and never reports a leak.
This patch not only causes leak false negatives, but also a number of other
problems, including false positives on some checkers.
What's worse, even though the program state contains a finite number of symbols,
the set of symbols that dies is potentially infinite. This means that is
impossible to compute the set of all dead symbols to pass off to the checkers
for cleaning up their part of the GDM.
No longer compute the dead set at all. Disallow iterating over dead symbols.
Disallow querying if any symbols are dead. Remove the API for marking symbols
as dead, as it is no longer necessary. Update checkers accordingly.
Differential Revision: https://reviews.llvm.org/D18860
llvm-svn: 347953
If a pointer cast fails (evaluates to an UnknownVal, i.e. not implemented in the
analyzer) and such cast is in fact the last use of the pointer, the pointer
symbol is no longer referenced by the program state and a leak is
(mis-)diagnosed.
"Escape" the pointer upon a failed cast, i.e. inform the checker that we can no
longer reliably track it.
Differential Revision: https://reviews.llvm.org/D45698
llvm-svn: 330380
Change the analyzer's modeling of memcpy to be more precise when copying into fixed-size
array fields. With this change, instead of invalidating the entire containing region the
analyzer now invalidates only offsets for the array itself when it can show that the
memcpy stays within the bounds of the array.
This addresses false positive memory leak warnings of the kind reported by
krzysztof in https://llvm.org/bugs/show_bug.cgi?id=22954
(This is the second attempt, now with assertion failures resolved.)
A patch by Pierre Gousseau!
Differential Revision: http://reviews.llvm.org/D12571
llvm-svn: 248516
Change the analyzer's modeling of memcpy to be more precise when copying into fixed-size
array fields. With this change, instead of invalidating the entire containing region the
analyzer now invalidates only offsets for the array itself when it can show that the
memcpy stays within the bounds of the array.
This addresses false positive memory leak warnings of the kind reported by
krzysztof in https://llvm.org/bugs/show_bug.cgi?id=22954
A patch by Pierre Gousseau!
Differential Revision: http://reviews.llvm.org/D11832
llvm-svn: 246345
Balázs Kéri