commit 79798a23637db7e5a4bb05c860b2932b3b1a3010 Author: David Goulet <dgoulet@ev0ke.net> Date: Tue Jun 2 16:37:11 2015 -0400 Set the open file limit to the current value before changing it If setrlimit() failed, max_out wasn't set in set_max_file_descriptors() ending in a state where we don't use ULIMIT_BUFFER for things like tor private key files. Also fix the set_max_file_descriptors() documentation. Fixes #16274 Signed-off-by: David Goulet <dgoulet@ev0ke.net> --- changes/bug16274 | 5 +++++ src/common/compat.c | 24 ++++++++++++++++-------- 2 files changed, 21 insertions(+), 8 deletions(-) diff --git a/changes/bug16274 b/changes/bug16274 new file mode 100644 index 0000000..4eec571 --- /dev/null +++ b/changes/bug16274 @@ -0,0 +1,5 @@ + o Minor bugfix (open file limit): + - Fix set_max_file_descriptors() to set by default the max open file + limit to the current limit in case setrlimit() fails so we at least + have a usable value; Fixes #16274; bugfix on tor-0.2.0.10-alpha~71; + Patch by dgoulet. diff --git a/src/common/compat.c b/src/common/compat.c index 3060817..28b8344 100644 --- a/src/common/compat.c +++ b/src/common/compat.c @@ -1600,15 +1600,23 @@ get_max_sockets(void) * tell Tor it's allowed to use. */ #define ULIMIT_BUFFER 32 /* keep 32 extra fd's beyond ConnLimit_ */ -/** Learn the maximum allowed number of file descriptors, and tell the system - * we want to use up to that number. (Some systems have a low soft limit, and - * let us set it higher.) +/** Learn the maximum allowed number of file descriptors, and tell the + * system we want to use up to that number. (Some systems have a low soft + * limit, and let us set it higher.) We compute this by finding the largest + * number that we can use. * - * We compute this by finding the largest number that we can use. - * If we can't find a number greater than or equal to <b>limit</b>, - * then we fail: return -1. + * If the limit is below the reserved file descriptor value (ULIMIT_BUFFER), + * return -1 and <b>max_out</b> is untouched. * - * Otherwise, return 0 and store the maximum we found inside <b>max_out</b>.*/ + * If we can't find a number greater than or equal to <b>limit</b>, then we + * fail by returning -1 and <b>max_out</b> is untouched. + * + * If we are unable to set the limit value because of setrlimit() failing, + * return -1 and <b>max_out</b> is set to the current maximum value returned + * by getrlimit(). + * + * Otherwise, return 0 and store the maximum we found inside <b>max_out</b> + * and set <b>max_sockets</b> with that value as well.*/ int set_max_file_descriptors(rlim_t limit, int *max_out) { @@ -1665,7 +1673,7 @@ set_max_file_descriptors(rlim_t limit, int *max_out) } /* Set the current limit value so if the attempt to set the limit to the * max fails at least we'll have a valid value of maximum sockets. */ - max_sockets = (int)rlim.rlim_cur - ULIMIT_BUFFER; + *max_out = max_sockets = (int)rlim.rlim_cur - ULIMIT_BUFFER; rlim.rlim_cur = rlim.rlim_max; if (setrlimit(RLIMIT_NOFILE, &rlim) != 0) {