From: Christoph Hellwig Date: Sun, 17 Sep 2017 21:06:45 +0000 (-0700) Subject: iomap: fix integer truncation issues in the zeroing and dirtying helpers X-Git-Tag: archive/raspbian/4.9.51-1+rpi1~7^2~31 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=ec0d46ef8b7e35b4f7c82bcf12afbe96b711350f;p=linux-4.9.git iomap: fix integer truncation issues in the zeroing and dirtying helpers commit e28ae8e428fefe2facd72cea9f29906ecb9c861d upstream. Fix the min_t calls in the zeroing and dirtying helpers to perform the comparisms on 64-bit types, which prevents them from incorrectly being truncated, and larger zeroing operations being stuck in a never ending loop. Special thanks to Markus Stockhausen for spotting the bug. Reported-by: Paul Menzel Tested-by: Paul Menzel Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/iomap.c b/fs/iomap.c index 798c291cbc75..a49db8806a3a 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -281,7 +281,7 @@ iomap_dirty_actor(struct inode *inode, loff_t pos, loff_t length, void *data, unsigned long bytes; /* Bytes to write to page */ offset = (pos & (PAGE_SIZE - 1)); - bytes = min_t(unsigned long, PAGE_SIZE - offset, length); + bytes = min_t(loff_t, PAGE_SIZE - offset, length); rpage = __iomap_read_page(inode, pos); if (IS_ERR(rpage)) @@ -376,7 +376,7 @@ iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t count, unsigned offset, bytes; offset = pos & (PAGE_SIZE - 1); /* Within page */ - bytes = min_t(unsigned, PAGE_SIZE - offset, count); + bytes = min_t(loff_t, PAGE_SIZE - offset, count); if (IS_DAX(inode)) status = iomap_dax_zero(pos, offset, bytes, iomap);