We were freeing non-existent pages which was causing a panic for a user who was suffering from ENOMEM. This patch fixes the problem. Thanks,
Reported-by: Jérôme Poulin <[email protected]> Signed-off-by: Josef Bacik <[email protected]> --- fs/btrfs/compression.c | 12 +++++++++--- 1 files changed, 9 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 43d1c5a..36eb5f2 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -577,6 +577,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, u64 em_start; struct extent_map *em; int ret = -ENOMEM; + int faili = 0; u32 *sums; tree = &BTRFS_I(inode)->io_tree; @@ -626,8 +627,11 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, for (pg_index = 0; pg_index < nr_pages; pg_index++) { cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS | __GFP_HIGHMEM); - if (!cb->compressed_pages[pg_index]) + if (!cb->compressed_pages[pg_index]) { + faili = pg_index - 1; + ret = -ENOMEM; goto fail2; + } } cb->nr_pages = nr_pages; @@ -713,8 +717,10 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, return 0; fail2: - for (pg_index = 0; pg_index < nr_pages; pg_index++) - free_page((unsigned long)cb->compressed_pages[pg_index]); + while (faili >= 0) { + __free_page(cb->compressed_pages[pg_index]); + faili--; + } kfree(cb->compressed_pages); fail1: -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
