X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fcapability.c;h=dcf7ce1a69ec58b252c4dcf1bc06ace259b5c48e;hp=b39e8e2359d3bc77ea67d52fe92b92370e850f47;hb=51ddf61540976fc7b09ce5ace707b27f3acc3871;hpb=615938651d3a4fd9253b08da00db22d451a8cef8 diff --git a/src/shared/capability.c b/src/shared/capability.c index b39e8e235..dcf7ce1a6 100644 --- a/src/shared/capability.c +++ b/src/shared/capability.c @@ -230,7 +230,6 @@ int capability_bounding_set_drop_usermode(uint64_t drop) { } int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilities) { - cap_value_t bits[sizeof(keep_capabilities)*8]; _cleanup_cap_free_ cap_t d = NULL; unsigned i, j = 0; int r; @@ -248,8 +247,8 @@ int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilities) { if (setgroups(0, NULL) < 0) return log_error_errno(errno, "Failed to drop auxiliary groups list: %m"); - /* Ensure we keep the permitted caps across the setresuid(), if we need them */ - if (prctl(PR_SET_KEEPCAPS, keep_capabilities != 0) < 0) + /* Ensure we keep the permitted caps across the setresuid() */ + if (prctl(PR_SET_KEEPCAPS, 1) < 0) return log_error_errno(errno, "Failed to enable keep capabilities flag: %m"); r = setresuid(uid, uid, uid); @@ -264,26 +263,27 @@ int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilities) { if (r < 0) return log_error_errno(r, "Failed to drop capabilities: %m"); - if (keep_capabilities == 0) /* All is gone, we can exit early */ - return 0; - /* Now upgrade the permitted caps we still kept to effective caps */ d = cap_init(); if (!d) return log_oom(); - for (i = 0; i < sizeof(keep_capabilities)*8; i++) - if (keep_capabilities & (1ULL << i)) - bits[j++] = i; + if (keep_capabilities) { + cap_value_t bits[sizeof(keep_capabilities)*8]; - if (cap_set_flag(d, CAP_EFFECTIVE, j, bits, CAP_SET) < 0 || - cap_set_flag(d, CAP_PERMITTED, j, bits, CAP_SET) < 0) { - log_error_errno(errno, "Failed to enable capabilities bits: %m"); - return -errno; - } + for (i = 0; i < sizeof(keep_capabilities)*8; i++) + if (keep_capabilities & (1ULL << i)) + bits[j++] = i; - if (cap_set_proc(d) < 0) - return log_error_errno(errno, "Failed to increase capabilities: %m"); + if (cap_set_flag(d, CAP_EFFECTIVE, j, bits, CAP_SET) < 0 || + cap_set_flag(d, CAP_PERMITTED, j, bits, CAP_SET) < 0) { + log_error_errno(errno, "Failed to enable capabilities bits: %m"); + return -errno; + } + + if (cap_set_proc(d) < 0) + return log_error_errno(errno, "Failed to increase capabilities: %m"); + } return 0; }