| Message ID | 20220616193529.56513-1-vishal.l.verma@intel.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | bbb2cb56f08d95ecf2c7c047a33cc3dd64eb7fde |
| Headers | show |
| Series | [ndctl] util/wrapper.c: Fix gcc warning in xrealloc() | expand |
Vishal Verma wrote: > A GCC update (12.1.1) now produces a warning in the xrealloc() wrapper > (originally copied from git, and used in strbuf operations): > > ../util/wrapper.c: In function ‘xrealloc’: > ../util/wrapper.c:34:31: warning: pointer ‘ptr’ may be used after ‘realloc’ [-Wuse-after-free] > 34 | ret = realloc(ptr, 1); > | ^~~~~~~~~~~~~~~ > > Pull in an updated definition for xrealloc() from the git project to fix this. > > Cc: Dan Williams <dan.j.williams@intel.com> > Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Looks like a faithful reproduction of what upstream git did minus the memory_limit_check() infra, but we can think about that later. Reviewed-by: Dan Williams <dan.j.williams@intel.com>
On Thu, 2022-06-16 at 13:30 -0700, Dan Williams wrote: > Vishal Verma wrote: > > A GCC update (12.1.1) now produces a warning in the xrealloc() > > wrapper > > (originally copied from git, and used in strbuf operations): > > > > ../util/wrapper.c: In function ‘xrealloc’: > > ../util/wrapper.c:34:31: warning: pointer ‘ptr’ may be used after > > ‘realloc’ [-Wuse-after-free] > > 34 | ret = realloc(ptr, 1); > > | ^~~~~~~~~~~~~~~ > > > > Pull in an updated definition for xrealloc() from the git project > > to fix this. > > > > Cc: Dan Williams <dan.j.williams@intel.com> > > Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> > > Looks like a faithful reproduction of what upstream git did minus the > memory_limit_check() infra, but we can think about that later. And minus the xmalloc() stuff, but I don't think we /need/ that (yet). > > Reviewed-by: Dan Williams <dan.j.williams@intel.com> Thanks!
diff --git a/util/wrapper.c b/util/wrapper.c index 026a54f..6adfde6 100644 --- a/util/wrapper.c +++ b/util/wrapper.c @@ -25,15 +25,15 @@ char *xstrdup(const char *str) void *xrealloc(void *ptr, size_t size) { - void *ret = realloc(ptr, size); - if (!ret && !size) - ret = realloc(ptr, 1); - if (!ret) { - ret = realloc(ptr, size); - if (!ret && !size) - ret = realloc(ptr, 1); - if (!ret) - die("Out of memory, realloc failed"); + void *ret; + + if (!size) { + free(ptr); + return malloc(1); } + + ret = realloc(ptr, size); + if (!ret) + die("Out of memory, realloc failed"); return ret; }
A GCC update (12.1.1) now produces a warning in the xrealloc() wrapper (originally copied from git, and used in strbuf operations): ../util/wrapper.c: In function ‘xrealloc’: ../util/wrapper.c:34:31: warning: pointer ‘ptr’ may be used after ‘realloc’ [-Wuse-after-free] 34 | ret = realloc(ptr, 1); | ^~~~~~~~~~~~~~~ Pull in an updated definition for xrealloc() from the git project to fix this. Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> --- util/wrapper.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) base-commit: 3e17210345482ec9795f1046c766564d3b8a0795