From a441bdc936f9258851be3fa04c108c37e0a497ab Mon Sep 17 00:00:00 2001 From: zeertzjq Date: Sun, 10 Mar 2024 16:58:01 +0800 Subject: vim-patch:9.1.0162: problem with writing extended attributes on failure (#27800) Problem: problem with writing extended attributes on failure Solution: Change return type to ssize_t and check listxattr's return value correctly on failure (Paul Tagliamonte) The existing logic will return when the listxattr call returns with the errno set to ENOTSUP (or a size of 0 bytes), without checking to see if listxattr actually failed. listxattr can fail with at least E2BIG, ENOTSUP, ERANGE, or anything that `stat(2)` can fail with (in my case; ENOENT from stat). The returned size is stored to a size_t, but the return type is a ssize_t. On failure, listxattr returns -1, which will get translated to size_t's MAX. If the listxattr call failed with anything other than ENOTSUP, this triggers a request for size_t MAX bytes. This means that, if the listxattr call fails with anything other than ENOTSUP on save, vim will error with `E342: Out of memory! (allocating 18446744073709551615 bytes)` (keen observers will note 18446744073709551615 is 0xffffffffffffffff) In reality, this is likely masking a different (usually filesystem?) error -- but at least it's an error being pushed to the user now, and we don't try to allocate size_t MAX bytes. I've opted to change the type that we store listxattr to from size_t to ssize_t, to match listxattr(2)'s signature, and to check for the -1 return value. Additionally, I've removed the errno check -- if we get a listxattr failure for any reason, we may as well bail without trying; it's not like we can even recover. closes: vim/vim#14169 https://github.com/vim/vim/commit/14759ded57447345ba11c11a99fd84344797862c Co-authored-by: Paul R. Tagliamonte --- src/nvim/os/fs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src') diff --git a/src/nvim/os/fs.c b/src/nvim/os/fs.c index ade745df2c..85caf4aa43 100644 --- a/src/nvim/os/fs.c +++ b/src/nvim/os/fs.c @@ -789,7 +789,7 @@ void os_copy_xattr(const char *from_file, const char *to_file) // get the length of the extended attributes ssize_t size = listxattr((char *)from_file, NULL, 0); // not supported or no attributes to copy - if (errno == ENOTSUP || size <= 0) { + if (size <= 0) { return; } char *xattr_buf = xmalloc((size_t)size); -- cgit