git: 51e94a4658d2 - main - LinuxKPI: fix possible NULL dereference in linuxkpi_page_frag_alloc()

The branch main has been updated by bz:

URL: https://cgit.FreeBSD.org/src/commit/?id=51e94a4658d23016dd0ae67c189a89f53281cbcd

commit 51e94a4658d23016dd0ae67c189a89f53281cbcd
Author:     Bjoern A. Zeeb <bz@FreeBSD.org>
AuthorDate: 2023-01-11 23:40:05 +0000
Commit:     Bjoern A. Zeeb <bz@FreeBSD.org>
CommitDate: 2023-01-11 23:40:05 +0000

    LinuxKPI: fix possible NULL dereference in linuxkpi_page_frag_alloc()
    
    Fix a possible NULL pointer deref in case alloc_pages() fails.
    This is theoretical so far as up to now no code in the tree uses
    linuxkpi_page_frag_alloc().
    
    Reported by:    Coverity via emaste
    Coverity ID:    1502345
    Sponsored by:   The FreeBSD Foundation
    MFC after:      3 days
    X-MFC-with:     55038a6306a570c9f2df89f5ad076de0f7d98152
---
 sys/compat/linuxkpi/common/src/linux_page.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/compat/linuxkpi/common/src/linux_page.c b/sys/compat/linuxkpi/common/src/linux_page.c
index 2bbe8f502cba..4c93d2f69354 100644
--- a/sys/compat/linuxkpi/common/src/linux_page.c
+++ b/sys/compat/linuxkpi/common/src/linux_page.c
@@ -451,6 +451,8 @@ linuxkpi_page_frag_alloc(struct page_frag_cache *pfc,
 	    "supported", __func__, fragsz));
 
 	pages = alloc_pages(gfp, flsl(howmany(fragsz, PAGE_SIZE) - 1));
+	if (pages == NULL)
+		return (NULL);
 	pfc->va = linux_page_address(pages);
 
 	/* Passed in as "count" to __page_frag_cache_drain(). Unused by us. */