From: Yee Cheng Chin Date: Sun, 20 Jul 2025 07:19:13 +0000 (+0200) Subject: patch 9.1.1567: crash when using inline diff mode X-Git-Tag: v9.1.1567^0 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c8b99e2d139cf72c567892e44939f2719f703fa8;p=thirdparty%2Fvim.git patch 9.1.1567: crash when using inline diff mode Problem: Crash when using inline diff mode (Ilya Grigoriev) Solution: Set tp_diffbuf to NULL when skipping a diff block (Yee Cheng Chin). Fix an array out of bounds crash when using diffopt+=inline:char when 4 or more buffers are being diff'ed. This happens when one of the blocks is empty. The inline highlight logic skips using that buffer's block, but when another buffer is used later and calls diff_read() to merge the diff blocks together, it could erroneously consider the empty block's diff info which has not been initialized, leaving to diff numbers that are invalid. Later on the diff num is used without bounds checking which leads to the crash. Fix this by making sure to unset tp_diffbuf to NULL when we skip a block, so diff_read() will not consider this buffer to be used within inline diff. Also, add more bounds checking just to be safe. closes: #17805 Signed-off-by: Yee Cheng Chin Signed-off-by: Christian Brabandt --- diff --git a/src/diff.c b/src/diff.c index 21fb748381..d86dbf1530 100644 --- a/src/diff.c +++ b/src/diff.c @@ -3391,6 +3391,11 @@ diff_find_change_inline_diff( diff_T *orig_diff = curtab->tp_first_diff; curtab->tp_first_diff = NULL; + // diff_read() also uses curtab->tp_diffbuf to determine what's an active + // buffer + buf_T *(orig_diffbuf[DB_COUNT]); + memcpy(orig_diffbuf, curtab->tp_diffbuf, sizeof(orig_diffbuf)); + // Buffers to populate mmfile 1/2 that would be passed to xdiff as memory // files. Use a grow array as it is not obvious how much exact space we // need. @@ -3412,7 +3417,12 @@ diff_find_change_inline_diff( continue; // skip buffer that isn't loaded if (dp->df_count[i] == 0) - continue; // skip buffer that don't have any texts in this block + { + // skip buffers that don't have any texts in this block so we don't + // end up marking the entire block as modified in multi-buffer diff + curtab->tp_diffbuf[i] = NULL; + continue; + } if (file1_idx == -1) file1_idx = i; @@ -3626,7 +3636,7 @@ diff_find_change_inline_diff( CLEAR_FIELD(change); for (int i = 0; i < DB_COUNT; i++) { - if (new_diff->df_lnum[i] == 0) + if (new_diff->df_lnum[i] <= 0) // should never be < 0. Checking just for safety. continue; linenr_T diff_lnum = new_diff->df_lnum[i] - 1; // use zero-index linenr_T diff_lnum_end = diff_lnum + new_diff->df_count[i]; @@ -3675,6 +3685,7 @@ done: diff_clear(curtab); curtab->tp_first_diff = orig_diff; + memcpy(curtab->tp_diffbuf, orig_diffbuf, sizeof(orig_diffbuf)); ga_clear(&file1_str); ga_clear(&file2_str); diff --git a/src/testdir/dumps/Test_diff_inline_multibuffer_empty_block_01.dump b/src/testdir/dumps/Test_diff_inline_multibuffer_empty_block_01.dump new file mode 100644 index 0000000000..fad9aac399 --- /dev/null +++ b/src/testdir/dumps/Test_diff_inline_multibuffer_empty_block_01.dump @@ -0,0 +1,20 @@ +| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|1| @10||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|1| @7||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|1| @8||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|1| @7 +| +0#0000e05#a8a8a8255@1|1+0#0000000#ffd7ff255|2+2&#ff404010|3|4|5|6|7|8|9|0+0&#ffd7ff255|a|b|c|d+2&#ff404010|e| +0&#ffd7ff255@2||+1&#ffffff0| +0#0000e05#a8a8a8255@1|1+0#0000000#ffd7ff255|2+2&#ff404010|3|4|5|6|7|-@1|0+0&#ffd7ff255|a|b|c|-+2&#ff404010|e||+1&#ffffff0| +0#0000e05#a8a8a8255@1|-+0#4040ff13#afffff255@15||+1#0000000#ffffff0| +0#0000e05#a8a8a8255@1|1+0#0000000#ffd7ff255|?+2&#ff404010@6|9|0+0&#ffd7ff255|a|b|c|d+2&#ff404010|? +| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|2| @10||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|2| @7||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|2| @8||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|n|c|h|o|r|2| @7 +|~+0#4040ff13&| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|~| @18||+1#0000000&|~+0#4040ff13&| @15||+1#0000000&|~+0#4040ff13&| @16||+1#0000000&|~+0#4040ff13&| @15 +|X+3#0000000&|d|i|f|i|l|e|1| @1|1|,|1| @3|A|l@1| |<+1&&|d|i|f|i|l|e|2| |1|,|1| @1|A|l@1| |<|d|i|f|i|l|e|3| |1|,|1| @2|A|l@1| |<|d|i|f|i|l|e|4| |1|,|1| @1|A|l@1 +|:+0&&> @73 diff --git a/src/testdir/test_diffmode.vim b/src/testdir/test_diffmode.vim index dc5dcc9a5e..eee23729a1 100644 --- a/src/testdir/test_diffmode.vim +++ b/src/testdir/test_diffmode.vim @@ -2636,6 +2636,22 @@ func Test_diff_inline_multibuffer() call StopVimInTerminal(buf) endfunc +" Test that when using multi-buffer diff, an empty block would be correctly +" skipped in the result, without resulting in invalid states or crashes. +func Test_diff_inline_multibuffer_empty_block() + CheckScreendump + + call writefile(['anchor1', '1234567890abcde', 'anchor2'], 'Xdifile1') + call writefile(['anchor1', '1234567--0abc-e', 'anchor2'], 'Xdifile2') + call writefile(['anchor1', 'anchor2'], 'Xdifile3') + call writefile(['anchor1', '1???????90abcd?', 'anchor2'], 'Xdifile4') + + let buf = RunVimInTerminal('-d Xdifile1 Xdifile2 Xdifile3 Xdifile4', {}) + call VerifyInternal(buf, "Test_diff_inline_multibuffer_empty_block_01", " diffopt+=inline:char") + + call StopVimInTerminal(buf) +endfunc + func Test_diffget_diffput_linematch() CheckScreendump call delete('.Xdifile1.swp') diff --git a/src/version.c b/src/version.c index a908f1179a..3b3f8ac979 100644 --- a/src/version.c +++ b/src/version.c @@ -719,6 +719,8 @@ static char *(features[]) = static int included_patches[] = { /* Add new patch number below this line */ +/**/ + 1567, /**/ 1566, /**/