2020-03-27 19:58:40

by Gustavo A. R. Silva

Subject: [PATCH][next] btrfs: inode: Fix uninitialized variable bug

geom.len is being used without being properly initialized, previously.

Fix this by placing ASSERT(geom.len <= INT_MAX); after geom.len has been
initialized.

Addresses-Coverity-ID: 1491912 ("Uninitialized scalar variable")
Fixes: 1eb52c8bd8d6 ("btrfs: get rid of one layer of bios in direct I/O")
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
fs/btrfs/inode.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index fce94591e092..00ea02268f54 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7637,7 +7637,6 @@ static void btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
else
async_submit = 1;

- ASSERT(geom.len <= INT_MAX);
do {
ret = btrfs_get_io_geometry(fs_info, btrfs_op(dio_bio),
start_sector << 9, submit_len,
@@ -7647,6 +7646,8 @@ static void btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
goto out_err;
}

+ ASSERT(geom.len <= INT_MAX);
+
clone_len = min_t(int, submit_len, geom.len);

/*
--
2.26.0

2020-04-01 16:03:02

by David Sterba

Subject: Re: [PATCH][next] btrfs: inode: Fix uninitialized variable bug

On Fri, Mar 27, 2020 at 03:01:35PM -0500, Gustavo A. R. Silva wrote:
> geom.len is being used without being properly initialized, previously.
>
> Fix this by placing ASSERT(geom.len <= INT_MAX); after geom.len has been
> initialized.
>
> Addresses-Coverity-ID: 1491912 ("Uninitialized scalar variable")
> Fixes: 1eb52c8bd8d6 ("btrfs: get rid of one layer of bios in direct I/O")

Thanks. This is in a development branch so the fixup can be folded in,
we're expecting more revisions of the patchset anyway. CCing Omar.