From: Namjae Jeon Date: Thu, 2 Jul 2026 01:31:44 +0000 (+0900) Subject: ntfs: fix WARN_ON for resident attribute in ntfs_map_runlist_nolock() X-Git-Tag: v7.2-rc3~20^2~4 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b8d6c528e9d57d263fee1a648409f84a68b2561d;p=thirdparty%2Fkernel%2Flinux.git ntfs: fix WARN_ON for resident attribute in ntfs_map_runlist_nolock() When ntfs_map_runlist_nolock() needs to look up the attribute extent containing a target VCN (ctx_needs_reset == true), it calls ntfs_attr_lookup() and then expects the result to be a non-resident attribute, since only non-resident attributes have a mapping pairs array to decompress. A crafted NTFS image can place a resident attribute where a non-resident one is expected, causing ntfs_attr_lookup() to succeed but return a resident attribute record. Previously this was caught only by a WARN_ON(), which does not stop execution. The code then falls through to read a->data.non_resident.highest_vcn from what is actually a resident attribute, accessing the wrong union member and corrupting the VCN range check. The caller path triggering this warning during mount is: ntfs_map_runlist_nolock ntfs_empty_logfile load_system_files ntfs_fill_super In this path ctx is NULL, so ntfs_map_runlist_nolock() allocates a temporary search context internally and sets ctx_needs_reset = true. The existing resident-attribute guard in the ctx != NULL branch already returns -EIO silently for the same condition; make the ctx_needs_reset path consistent by replacing the WARN_ON() with the same -EIO error return. This causes the crafted image to be rejected with a mount error instead of triggering a kernel warning. Fixes: 495e90fa3348 ("ntfs: update attrib operations") Cc: stable@vger.kernel.org Reported-by: Sangho Lee Signed-off-by: Namjae Jeon --- diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c index a99b84751eb1..e5e3bc03ad49 100644 --- a/fs/ntfs/attrib.c +++ b/fs/ntfs/attrib.c @@ -175,7 +175,10 @@ int ntfs_map_runlist_nolock(struct ntfs_inode *ni, s64 vcn, struct ntfs_attr_sea err = -EIO; goto err_out; } - WARN_ON(!ctx->attr->non_resident); + if (unlikely(!ctx->attr->non_resident)) { + err = -EIO; + goto err_out; + } } a = ctx->attr; /*