The bulkstat family of ioctls are problematic on x32, because there is
a mixup of native 32-bit and 64-bit conventions: the xfs_bulkstat struct
contains pointers and 32-bit integers so that fits the native 32-bit
layout fine. However, one of those pointers is subsequently used to
refer to one of several structs which, on x32, all follow the native
64-bit way.
Fortunately the pointer chasing seems to end there, and the functions to
deal with this abstract things pretty well. We just need a little tweak
to pass the right formatting function if called from x32 mode.
Signed-off-by: Nick Bowler <nbowler@xxxxxxxxxx>
---
fs/xfs/xfs_ioctl32.c | 25 +++++++++++++++++++++----
1 file changed, 21 insertions(+), 4 deletions(-)
diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
index fba115f4103a..6a759c0ffb54 100644
--- a/fs/xfs/xfs_ioctl32.c
+++ b/fs/xfs/xfs_ioctl32.c
@@ -241,6 +241,23 @@ xfs_compat_ioc_bulkstat(
int done;
int error;
+ /*
+ * These functions and size are used later to handle individual
+ * entries; x32 is annoying and needs different functions.
+ */
+ inumbers_fmt_pf inumbers_func = xfs_inumbers_fmt_compat;
+ bulkstat_one_pf bs_one_func = xfs_bulkstat_one_compat;
+ size_t bs_one_size = sizeof(compat_xfs_bstat_t);
+
+#ifdef CONFIG_X86_X32
+ if (in_x32_syscall()) {
+ /* x32 matches native amd64 bstat and inogrp layout */
+ inumbers_func = xfs_inumbers_fmt;
+ bs_one_func = xfs_bulkstat_one;
+ bs_one_size = sizeof(xfs_bstat_t);
+ }
+#endif
+
/* done = 1 if there are more stats to get and if bulkstat */
/* should be called again (unused here, but used in dmapi) */
@@ -272,15 +289,15 @@ xfs_compat_ioc_bulkstat(
if (cmd == XFS_IOC_FSINUMBERS_32) {
error = xfs_inumbers(mp, &inlast, &count,
- bulkreq.ubuffer, xfs_inumbers_fmt_compat);
+ bulkreq.ubuffer, inumbers_func);
} else if (cmd == XFS_IOC_FSBULKSTAT_SINGLE_32) {
int res;
- error = xfs_bulkstat_one_compat(mp, inlast, bulkreq.ubuffer,
- sizeof(compat_xfs_bstat_t), NULL, &res);
+ error = bs_one_func(mp, inlast, bulkreq.ubuffer,
+ bs_one_size, NULL, &res);
} else if (cmd == XFS_IOC_FSBULKSTAT_32) {
error = xfs_bulkstat(mp, &inlast, &count,
- xfs_bulkstat_one_compat, sizeof(compat_xfs_bstat_t),
+ bs_one_func, bs_one_size,
bulkreq.ubuffer, &done);
} else
error = -EINVAL;
--
2.16.1
