From d43b0a43ca09d1f11cbe2612df6d8b0761a08591 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Sun, 25 Jan 2015 00:47:06 +0000 Subject: gr_equal(): Fix a crash that could occur if the first group's member list was longer than the second's. There is no need to compute and compare the member list lengths in a separate pass, since we now just return false when comparing member names if the list lengths are not equal. MFC after: 2 weeks --- libutil/gr_util.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-) (limited to 'libutil') diff --git a/libutil/gr_util.c b/libutil/gr_util.c index 465efd9..b0b0b36 100644 --- a/libutil/gr_util.c +++ b/libutil/gr_util.c @@ -351,8 +351,6 @@ gr_fini(void) int gr_equal(const struct group *gr1, const struct group *gr2) { - int gr1_ndx; - int gr2_ndx; /* Check that the non-member information is the same. */ if (gr1->gr_name == NULL || gr2->gr_name == NULL) { @@ -368,7 +366,8 @@ gr_equal(const struct group *gr1, const struct group *gr2) if (gr1->gr_gid != gr2->gr_gid) return (false); - /* Check all members in both groups. + /* + * Check all members in both groups. * getgrnam can return gr_mem with a pointer to NULL. * gr_dup and gr_add strip out this superfluous NULL, setting * gr_mem to NULL for no members. @@ -376,22 +375,18 @@ gr_equal(const struct group *gr1, const struct group *gr2) if (gr1->gr_mem != NULL && gr2->gr_mem != NULL) { int i; - for (i = 0; gr1->gr_mem[i] != NULL; i++) { + for (i = 0; + gr1->gr_mem[i] != NULL && gr2->gr_mem[i] != NULL; i++) { if (strcmp(gr1->gr_mem[i], gr2->gr_mem[i]) != 0) return (false); } - } - /* Count number of members in both structs */ - gr2_ndx = 0; - if (gr2->gr_mem != NULL) - for(; gr2->gr_mem[gr2_ndx] != NULL; gr2_ndx++) - /* empty */; - gr1_ndx = 0; - if (gr1->gr_mem != NULL) - for(; gr1->gr_mem[gr1_ndx] != NULL; gr1_ndx++) - /* empty */; - if (gr1_ndx != gr2_ndx) + if (gr1->gr_mem[i] != NULL || gr2->gr_mem[i] != NULL) + return (false); + } else if (gr1->gr_mem != NULL && gr1->gr_mem[0] != NULL) { return (false); + } else if (gr2->gr_mem != NULL && gr2->gr_mem[0] != NULL) { + return (false); + } return (true); } -- cgit v1.2.3-56-ge451