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Subject[PATCH 0/7] Fix a pile of 4GB file problems on 32-bit
Date
I caught a bug in my own code where I forgot to cast to loff_t before
shifting. So I thought I'd grep around and see if I could find any
other occurrences. I found a few that were clearly bugs, and they're
fixed below. There are other places where we don't cast, and I think
they're OK. For example, some places we have a 'nr_pages' being shifted
by PAGE_SHIFT, and that's probably OK because it's probably a single I/O.

Also, I didn't touch AFFS or ROMFS or some other filesystems which
probably have never seen a 4GB file in their lives. Might be worth
fixing to be sure nobody copies bad code from them, but not worth cc'ing
stable for.

I didn't look for SECTOR_SHIFT or SECTOR_SIZE (or bare 9/512), just
PAGE_SIZE and PAGE_SHIFT.

I can't find a GCC warning to enable for this pattern, so I filed
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97287

Matthew Wilcox (Oracle) (7):
9P: Cast to loff_t before multiplying
buffer: Promote to unsigned long long before shifting
ceph: Promote to unsigned long long before shifting
ocfs2: Promote to unsigned long long before shifting
btrfs: Promote to unsigned long long before shifting
btrfs: Promote to unsigned long long before shifting
btrfs: Promote to unsigned long long before multiplying

fs/9p/vfs_file.c | 4 ++--
fs/btrfs/ioctl.c | 6 +++---
fs/btrfs/raid56.c | 2 +-
fs/btrfs/scrub.c | 25 ++++++++++++++++---------
fs/buffer.c | 2 +-
fs/ceph/addr.c | 2 +-
fs/ocfs2/alloc.c | 2 +-
7 files changed, 25 insertions(+), 18 deletions(-)

--
2.28.0

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