6.1-stable review patch. If anyone has any objections, please let me know.
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From: Nikita Zhandarovich n.zhandarovich@fintech.ru
commit 1cade98cf6415897bf9342ee451cc5b40b58c638 upstream.
When dealing with large extents and calculating file offsets by summing up according extent offsets and lengths of unsigned int type, one may encounter possible integer overflow if the values are big enough.
Prevent this from happening by expanding one of the addends to (pgoff_t) type.
Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE.
Fixes: d323d005ac4a ("f2fs: support file defragment") Cc: stable@vger.kernel.org Signed-off-by: Nikita Zhandarovich n.zhandarovich@fintech.ru Reviewed-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/f2fs/extent_cache.c | 4 ++-- fs/f2fs/file.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)
--- a/fs/f2fs/extent_cache.c +++ b/fs/f2fs/extent_cache.c @@ -426,7 +426,7 @@ static unsigned int __free_extent_tree(s static void __drop_largest_extent(struct extent_tree *et, pgoff_t fofs, unsigned int len) { - if (fofs < et->largest.fofs + et->largest.len && + if (fofs < (pgoff_t)et->largest.fofs + et->largest.len && fofs + len > et->largest.fofs) { et->largest.len = 0; et->largest_updated = true; @@ -505,7 +505,7 @@ static bool __lookup_extent_tree(struct
if (type == EX_READ && et->largest.fofs <= pgofs && - et->largest.fofs + et->largest.len > pgofs) { + (pgoff_t)et->largest.fofs + et->largest.len > pgofs) { *ei = et->largest; ret = true; stat_inc_largest_node_hit(sbi); --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -2671,7 +2671,7 @@ static int f2fs_defragment_range(struct * block addresses are continuous. */ if (f2fs_lookup_read_extent_cache(inode, pg_start, &ei)) { - if (ei.fofs + ei.len >= pg_end) + if ((pgoff_t)ei.fofs + ei.len >= pg_end) goto out; }