From 4c94f80fc817bee0e59da39397391cf2409cf029 Mon Sep 17 00:00:00 2001 From: Philippe Cerfon Date: Tue, 6 Jun 2023 02:52:49 +0200 Subject: [PATCH 2/2] Cygwin: use new XATTR_{NAME,SIZE}_MAX instead of MAX_EA_{NAME,VALUE}_LEN Signed-off-by: Philippe Cerfon --- winsup/cygwin/ntea.cc | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/winsup/cygwin/ntea.cc b/winsup/cygwin/ntea.cc index a400fcb2b..70815649c 100644 --- a/winsup/cygwin/ntea.cc +++ b/winsup/cygwin/ntea.cc @@ -17,9 +17,11 @@ details. */ #include "tls_pbuf.h" #include #include +#include -#define MAX_EA_NAME_LEN 256 -#define MAX_EA_VALUE_LEN 65536 +/* On storage the `user.` prefix is not included but the terminating null byte + is needed.*/ +#define _XATTR_NAME_MAX_ONDISK_ (XATTR_NAME_MAX - strlen("user.") + 1) /* At least one maximum sized entry fits. CV 2014-04-04: NtQueryEaFile function chokes on buffers bigger than 64K @@ -27,13 +29,13 @@ details. */ on a remote share, at least on Windows 7 and later. In theory the buffer should have a size of - sizeof (FILE_FULL_EA_INFORMATION) + MAX_EA_NAME_LEN - + MAX_EA_VALUE_LEN + sizeof (FILE_FULL_EA_INFORMATION) + _XATTR_NAME_MAX_ONDISK_ + + XATTR_SIZE_MAX (65804 bytes), but we're opting for simplicity here, and a 64K buffer has the advantage that we can use a tmp_pathbuf buffer, rather than having to alloca 64K from stack. */ -#define EA_BUFSIZ MAX_EA_VALUE_LEN +#define EA_BUFSIZ XATTR_SIZE_MAX #define NEXT_FEA(p) ((PFILE_FULL_EA_INFORMATION) (p->NextEntryOffset \ ? (char *) p + p->NextEntryOffset : NULL)) @@ -55,7 +57,7 @@ read_ea (HANDLE hdl, path_conv &pc, const char *name, char *value, size_t size) returns the last EA entry of the file infinitely. Even utilizing the optional EaIndex only helps marginally. If you use that, the last EA in the file is returned twice. */ - char lastname[MAX_EA_NAME_LEN]; + char lastname[_XATTR_NAME_MAX_ONDISK_]; __try { @@ -95,7 +97,7 @@ read_ea (HANDLE hdl, path_conv &pc, const char *name, char *value, size_t size) __leave; } - if ((nlen = strlen (name)) >= MAX_EA_NAME_LEN) + if ((nlen = strlen (name)) >= _XATTR_NAME_MAX_ONDISK_) { set_errno (EINVAL); __leave; @@ -197,7 +199,7 @@ read_ea (HANDLE hdl, path_conv &pc, const char *name, char *value, size_t size) /* For compatibility with Linux, we always prepend "user." to the attribute name, so effectively we only support user attributes from a application point of view. */ - char tmpbuf[MAX_EA_NAME_LEN * 2]; + char tmpbuf[_XATTR_NAME_MAX_ONDISK_ * 2]; char *tp = stpcpy (tmpbuf, "user."); stpcpy (tp, fea->EaName); /* NTFS stores all EA names in uppercase unfortunately. To @@ -297,7 +299,7 @@ write_ea (HANDLE hdl, path_conv &pc, const char *name, const char *value, /* Skip "user." prefix. */ name += 5; - if ((nlen = strlen (name)) >= MAX_EA_NAME_LEN) + if ((nlen = strlen (name)) >= _XATTR_NAME_MAX_ONDISK_) { set_errno (EINVAL); __leave; -- 2.40.1