From 9df75cfc33830bc3aaf625728e01f3e80a1c711e Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Tue, 24 May 2016 22:48:33 +0200 Subject: affs: fix remount failure when there are no options changed [ Upstream commit 01d6e08711bf90bc4d7ead14a93a0cbd73b1896a ] Commit c8f33d0bec99 ("affs: kstrdup() memory handling") checks if the kstrdup function returns NULL due to out-of-memory condition. However, if we are remounting a filesystem with no change to filesystem-specific options, the parameter data is NULL. In this case, kstrdup returns NULL (because it was passed NULL parameter), although no out of memory condition exists. The mount syscall then fails with ENOMEM. This patch fixes the bug. We fail with ENOMEM only if data is non-NULL. The patch also changes the call to replace_mount_options - if we didn't pass any filesystem-specific options, we don't call replace_mount_options (thus we don't erase existing reported options). Fixes: c8f33d0bec99 ("affs: kstrdup() memory handling") Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- fs/affs/super.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/affs/super.c b/fs/affs/super.c index 3f89c9e05b40..cc7571201b4f 100644 --- a/fs/affs/super.c +++ b/fs/affs/super.c @@ -526,7 +526,7 @@ affs_remount(struct super_block *sb, int *flags, char *data) char *prefix = NULL; new_opts = kstrdup(data, GFP_KERNEL); - if (!new_opts) + if (data && !new_opts) return -ENOMEM; pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data); @@ -544,7 +544,8 @@ affs_remount(struct super_block *sb, int *flags, char *data) } flush_delayed_work(&sbi->sb_work); - replace_mount_options(sb, new_opts); + if (new_opts) + replace_mount_options(sb, new_opts); sbi->s_flags = mount_flags; sbi->s_mode = mode; -- cgit v1.2.3