From: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Date: Wed, 29 Sep 2021 16:29:52 +0000 (+0300)
Subject: fs/ntfs3: Check for NULL if ATTR_EA_INFO is incorrect
X-Git-Tag: v5.15-rc6~33^2~13
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=35afb70dcfe4eb445060dd955e5b67d962869ce5;p=thirdparty%2Fkernel%2Flinux.git

fs/ntfs3: Check for NULL if ATTR_EA_INFO is incorrect

This can be reason for reported panic
https://lore.kernel.org/ntfs3/f9de5807-2311-7374-afb0-bc5dffb522c0@gmail.com/
Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation")

Reported-by: Mohammad Rasim <mohammad.rasim96@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
---

diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c
index 9a53f809576d0..007602badd900 100644
--- a/fs/ntfs3/frecord.c
+++ b/fs/ntfs3/frecord.c
@@ -3080,7 +3080,9 @@ static bool ni_update_parent(struct ntfs_inode *ni, struct NTFS_DUP_INFO *dup,
 			const struct EA_INFO *info;
 
 			info = resident_data_ex(attr, sizeof(struct EA_INFO));
-			dup->ea_size = info->size_pack;
+			/* If ATTR_EA_INFO exists 'info' can't be NULL. */
+			if (info)
+				dup->ea_size = info->size_pack;
 		}
 	}