details: http://hg.nginx.org/nginx/rev/4df3d9fcdee8 branches: changeset: 6437:4df3d9fcdee8 user: Maxim Dounin <[email protected]> date: Tue Mar 15 18:26:17 2016 +0300 description: Truncation detection in sendfile() on Linux.
This addresses connection hangs as observed in ticket #504, and CPU hogs with "aio threads; sendfile on" as reported in the mailing list, see http://mailman.nginx.org/pipermail/nginx-ru/2016-March/057638.html. The alert is identical to one used on FreeBSD. diffstat: src/os/unix/ngx_linux_sendfile_chain.c | 26 ++++++++++++++++++++++++++ 1 files changed, 26 insertions(+), 0 deletions(-) diffs (43 lines): diff --git a/src/os/unix/ngx_linux_sendfile_chain.c b/src/os/unix/ngx_linux_sendfile_chain.c --- a/src/os/unix/ngx_linux_sendfile_chain.c +++ b/src/os/unix/ngx_linux_sendfile_chain.c @@ -292,6 +292,19 @@ eintr: } } + if (n == 0) { + /* + * if sendfile returns zero, then someone has truncated the file, + * so the offset became beyond the end of the file + */ + + ngx_log_error(NGX_LOG_ALERT, c->log, 0, + "sendfile() reported that \"%s\" was truncated at %O", + file->file->name.data, file->file_pos); + + return NGX_ERROR; + } + ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0, "sendfile: %z of %uz @%O", n, size, file->file_pos); @@ -354,6 +367,19 @@ ngx_linux_sendfile_thread(ngx_connection return NGX_ERROR; } + if (ctx->sent == 0) { + /* + * if sendfile returns zero, then someone has truncated the file, + * so the offset became beyond the end of the file + */ + + ngx_log_error(NGX_LOG_ALERT, c->log, 0, + "sendfile() reported that \"%s\" was truncated at %O", + file->file->name.data, file->file_pos); + + return NGX_ERROR; + } + *sent = ctx->sent; return (ctx->sent == ctx->size) ? NGX_DONE : NGX_AGAIN; _______________________________________________ nginx-devel mailing list [email protected] http://mailman.nginx.org/mailman/listinfo/nginx-devel
