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Differential D4153

index: remove side-effect from failed nt_init()
ClosedPublic

Authored by martinvonz on Aug 7 2018, 2:26 AM.

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rHGf7d8fb2ed8a8: index: remove side-effect from failed nt_init()
Summary

As pointed out by Yuya in the review of D4108, if we run into the
"overflow in nt_init" case (which I think normally happens only in
repos with at least 2^26=64Mi revisions), we would leave the node tree
half-initialized.

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rHG Mercurial
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Event Timeline

martinvonz created this revision.Aug 7 2018, 2:26 AM
Closed by commit rHGf7d8fb2ed8a8: index: remove side-effect from failed nt_init() (authored by martinvonz). · Explain WhyAug 7 2018, 8:52 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/cext/revlog.c (8 lines)

Diff 10048

mercurial/cext/revlog.c

{ {
/* rev==-2 happens to get encoded as 0, which is interpreted as not set */ /* rev==-2 happens to get encoded as 0, which is interpreted as not set */
return nt_insert(self, node, -2); return nt_insert(self, node, -2);
} }
static int nt_init(indexObject *self) static int nt_init(indexObject *self)
{ {
if (self->nt == NULL) { if (self->nt == NULL) {
if ((size_t)self->raw_length > INT_MAX / sizeof(nodetreenode)) {
PyErr_SetString(PyExc_ValueError, "overflow in nt_init");
return -1;
}
self->nt = PyMem_Malloc(sizeof(nodetree)); self->nt = PyMem_Malloc(sizeof(nodetree));
if (self->nt == NULL) { if (self->nt == NULL) {
PyErr_NoMemory(); PyErr_NoMemory();
return -1; return -1;
} }
if ((size_t)self->raw_length > INT_MAX / sizeof(nodetreenode)) {
PyErr_SetString(PyExc_ValueError, "overflow in nt_init");
return -1;
}
self->nt->capacity = self->raw_length < 4 self->nt->capacity = self->raw_length < 4
? 4 : (int)self->raw_length / 2; ? 4 : (int)self->raw_length / 2;
self->nt->nodes = calloc(self->nt->capacity, sizeof(nodetreenode)); self->nt->nodes = calloc(self->nt->capacity, sizeof(nodetreenode));
if (self->nt->nodes == NULL) { if (self->nt->nodes == NULL) {
PyMem_Free(self->nt); PyMem_Free(self->nt);
self->nt = NULL; self->nt = NULL;
PyErr_NoMemory(); PyErr_NoMemory();