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| author | Martin Kaiser <wireshark@kaiser.cx> | 2014-12-07 19:47:54 +0100 |
|---|---|---|
| committer | Anders Broman <a.broman58@gmail.com> | 2014-12-11 09:39:18 +0000 |
| commit | b7f8cd8a5d4fc98ef62fd7d503df2451f187eefd (patch) | |
| tree | 83a1b9aaf3d793e7422a080cacfd839492bc5591 /epan/tvbuff_zlib.c | |
| parent | 5570f8e24bb1b425ad14c232ff36ca48d8597410 (diff) | |
| download | wireshark-b7f8cd8a5d4fc98ef62fd7d503df2451f187eefd.tar.gz wireshark-b7f8cd8a5d4fc98ef62fd7d503df2451f187eefd.tar.bz2 wireshark-b7f8cd8a5d4fc98ef62fd7d503df2451f187eefd.zip | |
skip the extra field in the gzip header
it consists of two bytes xsize + xsize bytes of data
use an unsigned type for xsize
fail gracefully if the field is present but truncated
tvb_length_remaining > tvb_captured_length_remaining
Change-Id: I7f5138743c2d88abdd4f5f18d3c0292612ddb559
Reviewed-on: https://code.wireshark.org/review/5654
Reviewed-by: Anders Broman <a.broman58@gmail.com>
Diffstat (limited to 'epan/tvbuff_zlib.c')
| -rw-r--r-- | epan/tvbuff_zlib.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/epan/tvbuff_zlib.c b/epan/tvbuff_zlib.c index 17093222eb..0e6be80d0a 100644 --- a/epan/tvbuff_zlib.c +++ b/epan/tvbuff_zlib.c @@ -60,7 +60,7 @@ tvb_uncompress(tvbuff_t *tvb, const int offset, int comprlen) guint bufsiz; #ifdef TVB_Z_DEBUG guint inflate_passes = 0; - guint bytes_in = tvb_length_remaining(tvb, offset); + guint bytes_in = tvb_captured_length_remaining(tvb, offset); #endif if (tvb == NULL) { @@ -76,7 +76,7 @@ tvb_uncompress(tvbuff_t *tvb, const int offset, int comprlen) * Assume that the uncompressed data is at least twice as big as * the compressed size. */ - bufsiz = tvb_length_remaining(tvb, offset) * 2; + bufsiz = tvb_captured_length_remaining(tvb, offset) * 2; bufsiz = CLAMP(bufsiz, TVB_Z_MIN_BUFSIZ, TVB_Z_MAX_BUFSIZ); #ifdef TVB_Z_DEBUG @@ -204,9 +204,23 @@ tvb_uncompress(tvbuff_t *tvb, const int offset, int comprlen) c += 6; if (flags & (1 << 2)) { - /* An Extra field is present. */ - gint xsize = (gint)(*c | - (*(c + 1) << 8)); + /* An Extra field is present. It + consists of 2 bytes xsize and xsize + bytes of data. + Read byte-by-byte (least significant + byte first) to make sure we abort + cleanly when the xsize is truncated + after the first byte. */ + guint16 xsize = 0; + + if (c-compr < comprlen) { + xsize += *c; + c++; + } + if (c-compr < comprlen) { + xsize += *c << 8; + c++; + } c += xsize; } |