kdudka added a comment.
I was wondering why copying files in Krusader or Dolphin from a vfat-formatted memory card stopped working for me after update. After copying the first file, the transfer stopped progressing and the process ended up consuming 100% CPU forever. Later I discovered that the cause of the breakage was this patch: If fgetxattr() fails with ENOTSUP, the code loops indefinitely calling fgetxattr(). The following hotfix made copying of files in Krusader work again for me: --- a/src/ioslaves/file/file_unix.cpp +++ b/src/ioslaves/file/file_unix.cpp @@ -642,35 +642,35 @@ bool FileProtocol::copyXattrs(const int src_fd, const int dest_fd) ssize_t valuelen = 0; do { value.resize(valuelen); #if HAVE_SYS_XATTR_H && !defined(__stub_getxattr) && !defined(Q_OS_MAC) valuelen = fgetxattr(src_fd, key.constData(), value.data(), valuelen); #elif defined(Q_OS_MAC) valuelen = fgetxattr(src_fd, key.constData(), value.data(), valuelen, 0, 0); #elif HAVE_SYS_EXTATTR_H valuelen = extattr_get_fd(src_fd, EXTATTR_NAMESPACE_USER, key.constData(), valuelen == 0 ? nullptr : value.data(), valuelen); #endif if (valuelen > 0 && value.size() == 0) { continue; } if (valuelen > 0 && value.size() > 0) { break; } - if (valuelen == -1 && errno == ERANGE) { + if (valuelen == -1 && errno != ERANGE) { valuelen = 0; - continue; + break; } // happens when attr value is an empty string if (valuelen == 0) { break; } } while (true); // Write key:value pair on destination #if HAVE_SYS_XATTR_H && !defined(__stub_getxattr) && !defined(Q_OS_MAC) ssize_t destlen = fsetxattr(dest_fd, key.constData(), value.constData(), valuelen, 0); #elif defined(Q_OS_MAC) ssize_t destlen = fsetxattr(dest_fd, key.constData(), value.constData(), valuelen, 0, 0); #elif HAVE_SYS_EXTATTR_H ssize_t destlen = extattr_set_fd(dest_fd, EXTATTR_NAMESPACE_USER, key.constData(), value.constData(), valuelen); #endif if (destlen == -1 && errno == ENOTSUP) { However, the code might need bigger changes to cover all the cases. I do not fully understand the (IMO over-complicated) loops around flistxattr() and fgetxattr(). Note that the fact that one of them uses `while (true) { ... }` whereas the other one uses `do { ... } while (true)` does not improve code readability either. REVISION DETAIL https://phabricator.kde.org/D17816 To: arrowd, dfaure, chinmoyr, bruns, #frameworks, tmarshall, usta, cochise Cc: kdudka, usta, scheirle, tmarshall, arrowd, cfeck, bruns, phidrho, dhaumann, funkybomber, abika, pino, davidedmundson, ngraham, atha.kane, spoorun, nicolasfella, kde-frameworks-devel, LeGast00n, cblack, michaelh