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| author | Wilco Dijkstra <wdijkstr@arm.com> | 2018-09-19 16:50:18 +0100 |
|---|---|---|
| committer | Wilco Dijkstra <wdijkstr@arm.com> | 2018-09-19 16:50:18 +0100 |
| commit | 83a552b0bb9fc2a5e80a0ab3723c0a80ce1db9f2 (patch) | |
| tree | 4861e51f5b6524e080ca62aefceb6a1d052fc652 /string/strstr.c | |
| parent | d734727837b5135c4c4c540d8c53e5a06aa7556a (diff) | |
| download | glibc-83a552b0bb9fc2a5e80a0ab3723c0a80ce1db9f2.tar.gz glibc-83a552b0bb9fc2a5e80a0ab3723c0a80ce1db9f2.tar.xz glibc-83a552b0bb9fc2a5e80a0ab3723c0a80ce1db9f2.zip | |
Fix strstr bug with huge needles (bug 23637)
The generic strstr in GLIBC 2.28 fails to match huge needles. The optimized AVAILABLE macro reads ahead a large fixed amount to reduce the overhead of repeatedly checking for the end of the string. However if the needle length is larger than this, two_way_long_needle may confuse this as meaning the end of the string and return NULL. This is fixed by adding the needle length to the amount to read ahead. [BZ #23637] * string/test-strstr.c (pr23637): New function. (test_main): Add tests with longer needles. * string/strcasestr.c (AVAILABLE): Fix readahead distance. * string/strstr.c (AVAILABLE): Likewise.
Diffstat (limited to 'string/strstr.c')
| -rw-r--r-- | string/strstr.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/string/strstr.c b/string/strstr.c index 33acdc5442..f74d7189ed 100644 --- a/string/strstr.c +++ b/string/strstr.c @@ -33,8 +33,9 @@ #define RETURN_TYPE char * #define AVAILABLE(h, h_l, j, n_l) \ - (((j) + (n_l) <= (h_l)) || ((h_l) += __strnlen ((void*)((h) + (h_l)), 512), \ - (j) + (n_l) <= (h_l))) + (((j) + (n_l) <= (h_l)) \ + || ((h_l) += __strnlen ((void*)((h) + (h_l)), (n_l) + 512), \ + (j) + (n_l) <= (h_l))) #define CHECK_EOL (1) #define RET0_IF_0(a) if (!a) goto ret0 #define FASTSEARCH(S,C,N) (void*) strchr ((void*)(S), (C)) |