From: Theodore Ts'o <tytso@mit.edu>
Date: Wed, 24 Apr 2024 02:13:25 +0000 (-0400)
Subject: Fix coverity false positives introduced by the post-2038 changes
X-Git-Tag: v1.47.1-rc1~30
X-Git-Url: https://git.whamcloud.com/gitweb?a=commitdiff_plain;h=ec1c87f84bc4b3ca60c422f02c08b0e4e0543bd6;p=tools%2Fe2fsprogs.git

Fix coverity false positives introduced by the post-2038 changes

Commit ca8bc9240a00 ("Add post-2038 timestamp support...") did things
like casting a 64-bit unsigned integer into a signed 32-bit integer
deliberately; but Coverity thinks this is a bug.  So mask off the bits
to make it clear this was deliberate.

Addresses-Coverity-Bug: 1596519
Addresses-Coverity-Bug: 1596515
Addresses-Coverity-Bug: 1596514
Addresses-Coverity-Bug: 1596513
Addresses-Coverity-Bug: 1596511
Addresses-Coverity-Bug: 1596509
Addresses-Coverity-Bug: 1596508
Addresses-Coverity-Bug: 1596504
Addresses-Coverity-Bug: 1596502
Addresses-Coverity-Bug: 1596501
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---

diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 9ecbb50..a325913 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -584,7 +584,8 @@ static inline __u32 __encode_extra_time(time_t seconds, __u32 nsec)
 	__u32 extra = 0;
 
 #if (SIZEOF_TIME_T > 4)
-	extra = ((seconds - (__s32)seconds) >> 32) & EXT4_EPOCH_MASK;
+	extra = ((seconds - (__s32)(seconds & 0xffffffff)) >> 32) &
+		EXT4_EPOCH_MASK;
 #endif
 	return extra | (nsec << EXT4_EPOCH_BITS);
 }
@@ -610,7 +611,7 @@ static inline __u32 __decode_extra_nsec(__u32 extra)
 do {									      \
 	if (ext2fs_inode_includes(ext2fs_inode_actual_size(inode),	      \
 				  field ## _extra)) {			      \
-		(inode)->field = (__s32)sec;				      \
+		(inode)->field = (__s32)(sec & 0xfffffff);		      \
 		((struct ext2_inode_large *)(inode))->field ## _extra =       \
 			__encode_extra_time(sec, 0);			      \
 	} else {							      \
@@ -627,7 +628,7 @@ static inline void __sb_set_tstamp(__u32 *lo, __u8 *hi, time_t seconds)
 {
 	*lo = seconds & 0xffffffff;
 #if (SIZEOF_TIME_T > 4)
-	*hi = seconds >> 32;
+	*hi = (seconds >> 32) & EXT4_EPOCH_MASK;
 #else
 	*hi = 0;
 #endif