Check the 32-bit limits using sizeof instead of cpp ifdefs so that we
can get rid of BITS_PER_LONG.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
repair/bmap.c | 23 +++++++++++++++--------
repair/bmap.h | 13 -------------
2 files changed, 15 insertions(+), 21 deletions(-)
diff --git a/repair/bmap.c b/repair/bmap.c
index cd1a8b07b..7e32fff33 100644
--- a/repair/bmap.c
+++ b/repair/bmap.c
@@ -22,6 +22,15 @@
pthread_key_t dblkmap_key;
pthread_key_t ablkmap_key;
+/*
+ * For 32 bit platforms, we are limited to extent arrays of 2^31 bytes, which
+ * limits the number of extents in an inode we can check. If we don't limit the
+ * valid range, we can overflow the BLKMAP_SIZE() calculation and allocate less
+ * memory than we think we needed, and hence walk off the end of the array and
+ * corrupt memory.
+ */
+#define BLKMAP_NEXTS32_MAX ((INT_MAX / sizeof(bmap_ext_t)) - 1)
+
blkmap_t *
blkmap_alloc(
xfs_extnum_t nex,
@@ -35,8 +44,7 @@ blkmap_alloc(
if (nex < 1)
nex = 1;
-#if (BITS_PER_LONG == 32) /* on 64-bit platforms this is never true */
- if (nex > BLKMAP_NEXTS_MAX) {
+ if (sizeof(long) == 4 && nex > BLKMAP_NEXTS32_MAX) {
do_warn(
_("Number of extents requested in blkmap_alloc (%llu) overflows 32 bits.\n"
"If this is not a corruption, then you will need a 64 bit system\n"
@@ -44,7 +52,6 @@ blkmap_alloc(
(unsigned long long)nex);
return NULL;
}
-#endif
key = whichfork ? ablkmap_key : dblkmap_key;
blkmap = pthread_getspecific(key);
@@ -278,20 +285,20 @@ blkmap_grow(
ASSERT(pthread_getspecific(key) == blkmap);
}
-#if (BITS_PER_LONG == 32) /* on 64-bit platforms this is never true */
- if (new_naexts > BLKMAP_NEXTS_MAX) {
+ if (sizeof(long) == 4 && new_naexts > BLKMAP_NEXTS32_MAX) {
do_error(
_("Number of extents requested in blkmap_grow (%d) overflows 32 bits.\n"
"You need a 64 bit system to repair this filesystem.\n"),
new_naexts);
return NULL;
}
-#endif
+
if (new_naexts <= 0) {
do_error(
_("Number of extents requested in blkmap_grow (%d) overflowed the\n"
- "maximum number of supported extents (%d).\n"),
- new_naexts, BLKMAP_NEXTS_MAX);
+ "maximum number of supported extents (%ld).\n"),
+ new_naexts,
+ sizeof(long) == 4 ? BLKMAP_NEXTS32_MAX : INT_MAX);
return NULL;
}
diff --git a/repair/bmap.h b/repair/bmap.h
index 4b588df8c..df9602b31 100644
--- a/repair/bmap.h
+++ b/repair/bmap.h
@@ -28,19 +28,6 @@ typedef struct blkmap {
#define BLKMAP_SIZE(n) \
(offsetof(blkmap_t, exts) + (sizeof(bmap_ext_t) * (n)))
-/*
- * For 32 bit platforms, we are limited to extent arrays of 2^31 bytes, which
- * limits the number of extents in an inode we can check. If we don't limit the
- * valid range, we can overflow the BLKMAP_SIZE() calculation and allocate less
- * memory than we think we needed, and hence walk off the end of the array and
- * corrupt memory.
- */
-#if BITS_PER_LONG == 32
-#define BLKMAP_NEXTS_MAX ((INT_MAX / sizeof(bmap_ext_t)) - 1)
-#else
-#define BLKMAP_NEXTS_MAX INT_MAX
-#endif
-
extern pthread_key_t dblkmap_key;
extern pthread_key_t ablkmap_key;
--
2.39.2
