This is a note to let you know that I've just added the patch titled NFSv4.2: fix error handling in nfs42_proc_getxattr to the 6.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfsv4.2-fix-error-handling-in-nfs42_proc_getxattr.patch and it can be found in the queue-6.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 92598baddb560829e2d578deeceed592d1db3aec Author: Fedor Pchelkin <pchelkin@xxxxxxxxx> Date: Tue Jul 25 14:58:58 2023 +0300 NFSv4.2: fix error handling in nfs42_proc_getxattr [ Upstream commit 4e3733fd2b0f677faae21cf838a43faf317986d3 ] There is a slight issue with error handling code inside nfs42_proc_getxattr(). If page allocating loop fails then we free the failing page array element which is NULL but __free_page() can't deal with NULL args. Found by Linux Verification Center (linuxtesting.org). Fixes: a1f26739ccdc ("NFSv4.2: improve page handling for GETXATTR") Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx> Reviewed-by: Benjamin Coddington <bcodding@xxxxxxxxxx> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c index 93e306bf4430f..5d7e0511f3513 100644 --- a/fs/nfs/nfs42proc.c +++ b/fs/nfs/nfs42proc.c @@ -1360,7 +1360,6 @@ ssize_t nfs42_proc_getxattr(struct inode *inode, const char *name, for (i = 0; i < np; i++) { pages[i] = alloc_page(GFP_KERNEL); if (!pages[i]) { - np = i + 1; err = -ENOMEM; goto out; } @@ -1384,8 +1383,8 @@ ssize_t nfs42_proc_getxattr(struct inode *inode, const char *name, } while (exception.retry); out: - while (--np >= 0) - __free_page(pages[np]); + while (--i >= 0) + __free_page(pages[i]); kfree(pages); return err;