From c8db0d7662af5aa4d43c4e61fb09715b8436bdab Mon Sep 17 00:00:00 2001 From: Lubomir Rintel Date: Tue, 3 May 2016 22:15:49 +0200 Subject: [PATCH 8/8] strbuf: set the proper character when creating new nodes Commit 82501b3fc added an early break when a terminal node is found to incorrect place -- before setting c. This caused trie to be built that does not correspond to what it points to in buffer, causing incorrect deduplications: # cat /etc/udev/rules.d/99-bug.rules ENV{FOO}=="0" ENV{xx0}=="BAR" ENV{BAZ}=="00" # udevadm test * RULE /etc/udev/rules.d/99-bug.rules:1, token: 0, count: 2, label: '' M ENV match 'FOO' '0'(plain) * RULE /etc/udev/rules.d/99-bug.rules:2, token: 2, count: 2, label: '' M ENV match 'xx0' 'BAR'(plain) * RULE /etc/udev/rules.d/99-bug.rules:3, token: 4, count: 2, label: '' M ENV match 'BAZ' 'x0'(plain) * END The addition of "xx0" following "0" will cause a trie like this to be created: c=\0 c=0 "0" c=0 "xx0" <-- note the c is incorrect here, causing "00" to be c=O "FOO" deduplicated to it c=R "BAR" This in effect caused the usb_modeswitch rule for Huawei modems to never match and this never be switched to serial mode from mass storage. (cherry picked from commit c45606eb95a7171b0dc801e91d35034957ad5e9e) Resolves: #1357822 --- src/basic/strbuf.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/basic/strbuf.c b/src/basic/strbuf.c index dac2881..79eef6c 100644 --- a/src/basic/strbuf.c +++ b/src/basic/strbuf.c @@ -156,12 +156,13 @@ ssize_t strbuf_add_string(struct strbuf *str, const char *s, size_t len) { return off; } + c = s[len - 1 - depth]; + /* bsearch is not allowed on a NULL sequence */ if (node->children_count == 0) break; /* lookup child node */ - c = s[len - 1 - depth]; search.c = c; child = bsearch(&search, node->children, node->children_count, sizeof(struct strbuf_child_entry), -- 2.7.4