| Message ID | 2f23492a3861a3ebddbf1f811296e98143b9b8f4.1677245356.git.edwin.torok@cloud.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fix memory leaks reported by GCC -fanalyzer | expand |
On 24/02/2023 1:36 pm, Edwin Török wrote: > From: Edwin Török <edwin.torok@cloud.com> > > From `man 2 realloc`: > `If realloc() fails, the original block is left untouched; it is not freed or moved.` > > Found using GCC -fanalyzer: > ``` > | 184 | backup->entries = realloc(backup->entries, > | | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > | | | | | > | | | | (91) when ‘realloc’ fails > | | | (92) ‘old_ptes.entries’ leaks here; was allocated at (44) > | | (90) ...to here > ``` > > Signed-off-by: Edwin Török <edwin.torok@cloud.com> In terms of the fix, Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>, but > --- > tools/libs/guest/xg_offline_page.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/tools/libs/guest/xg_offline_page.c b/tools/libs/guest/xg_offline_page.c > index c594fdba41..a8bcea768b 100644 > --- a/tools/libs/guest/xg_offline_page.c > +++ b/tools/libs/guest/xg_offline_page.c > @@ -181,10 +181,13 @@ static int backup_ptes(xen_pfn_t table_mfn, int offset, > > if (backup->max == backup->cur) > { > - backup->entries = realloc(backup->entries, > + void* orig = backup->entries; void *orig, and a newline. > + backup->entries = realloc(orig, > backup->max * 2 * sizeof(struct pte_backup_entry)); > - if (backup->entries == NULL) > + if (backup->entries == NULL) { Newline. Can be fixed on commit. ~Andrew > + free(orig); > return -1; > + } > else > backup->max *= 2; > }
diff --git a/tools/libs/guest/xg_offline_page.c b/tools/libs/guest/xg_offline_page.c index c594fdba41..a8bcea768b 100644 --- a/tools/libs/guest/xg_offline_page.c +++ b/tools/libs/guest/xg_offline_page.c @@ -181,10 +181,13 @@ static int backup_ptes(xen_pfn_t table_mfn, int offset, if (backup->max == backup->cur) { - backup->entries = realloc(backup->entries, + void* orig = backup->entries; + backup->entries = realloc(orig, backup->max * 2 * sizeof(struct pte_backup_entry)); - if (backup->entries == NULL) + if (backup->entries == NULL) { + free(orig); return -1; + } else backup->max *= 2; }