From f7ac9e71b18fa7314151f2ab65ee0bdd2ea89c07 Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Tue, 15 Dec 2015 12:25:56 +0100 Subject: login, mount: fix __SC_GETPW_R_SIZE_MAX usage sysconf(_SC_GETPW_R_SIZE_MAX) returns initial suggested size for pwd buffer (see getpwnam_r man page or POSIX). This is not large enough in some cases. Yes, this sysconf option is misnamed (should be _SC_GETPW_R_SIZE_MIN). Signed-off-by: Karel Zak --- libmount/src/utils.c | 25 ++++++------------------- 1 file changed, 6 insertions(+), 19 deletions(-) (limited to 'libmount/src') diff --git a/libmount/src/utils.c b/libmount/src/utils.c index e57eb33ba..39f6c851e 100644 --- a/libmount/src/utils.c +++ b/libmount/src/utils.c @@ -635,16 +635,6 @@ int mnt_get_filesystems(char ***filesystems, const char *pattern) return rc; } -static size_t get_pw_record_size(void) -{ -#ifdef _SC_GETPW_R_SIZE_MAX - long sz = sysconf(_SC_GETPW_R_SIZE_MAX); - if (sz > 0) - return sz; -#endif - return 16384; -} - /* * Returns an allocated string with username or NULL. */ @@ -652,14 +642,13 @@ char *mnt_get_username(const uid_t uid) { struct passwd pwd; struct passwd *res; - size_t sz = get_pw_record_size(); char *buf, *username = NULL; - buf = malloc(sz); + buf = malloc(UL_GETPW_BUFSIZ); if (!buf) return NULL; - if (!getpwuid_r(uid, &pwd, buf, sz, &res) && res) + if (!getpwuid_r(uid, &pwd, buf, UL_GETPW_BUFSIZ, &res) && res) username = strdup(pwd.pw_name); free(buf); @@ -671,17 +660,16 @@ int mnt_get_uid(const char *username, uid_t *uid) int rc = -1; struct passwd pwd; struct passwd *pw; - size_t sz = get_pw_record_size(); char *buf; if (!username || !uid) return -EINVAL; - buf = malloc(sz); + buf = malloc(UL_GETPW_BUFSIZ); if (!buf) return -ENOMEM; - if (!getpwnam_r(username, &pwd, buf, sz, &pw) && pw) { + if (!getpwnam_r(username, &pwd, buf, UL_GETPW_BUFSIZ, &pw) && pw) { *uid= pw->pw_uid; rc = 0; } else { @@ -699,17 +687,16 @@ int mnt_get_gid(const char *groupname, gid_t *gid) int rc = -1; struct group grp; struct group *gr; - size_t sz = get_pw_record_size(); char *buf; if (!groupname || !gid) return -EINVAL; - buf = malloc(sz); + buf = malloc(UL_GETPW_BUFSIZ); if (!buf) return -ENOMEM; - if (!getgrnam_r(groupname, &grp, buf, sz, &gr) && gr) { + if (!getgrnam_r(groupname, &grp, buf, UL_GETPW_BUFSIZ, &gr) && gr) { *gid= gr->gr_gid; rc = 0; } else { -- cgit v1.2.3-55-g7522