git: accbd5ad06c3 - releng/14.0 - vfs cache: Fallback to namei to resolve symlinks with leading / in target for non-native ABI

[Dmitry Chagin]

The branch releng/14.0 has been updated by dchagin:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=accbd5ad06c3eeb17d75cde05597f70f1fedb061

commit accbd5ad06c3eeb17d75cde05597f70f1fedb061
Author:     Dmitry Chagin <dcha...@freebsd.org>
AuthorDate: 2023-10-19 10:33:58 +0000
Commit:     Dmitry Chagin <dcha...@freebsd.org>
CommitDate: 2023-10-22 18:46:22 +0000

    vfs cache: Fallback to namei to resolve symlinks with leading / in target 
for non-native ABI
    
    This is a temporary solution to fix PR before release.
    During 15.0 it's necessary to refactor symlinks handling
    between vfs & namecache.
    
    Approved by:            re (gjb)
    PR:                     273414
    Reported by:            Vincent Milum Jr, Dan Kotowski, glebius
    Tested by:              Dan Kotowski, glebius
    Reviewed by:
    Differential Revision:  https://reviews.freebsd.org/D41806
    MFC after:              3 days
    
    (cherry picked from commit bb8ecf259f96510b9c2146d846403393543061b7)
    (cherry picked from commit b84a836ef02de42e262ce44d46c859be288df4b0)
---
 sys/kern/vfs_cache.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c
index 115d0bdd3993..8917666950c1 100644
--- a/sys/kern/vfs_cache.c
+++ b/sys/kern/vfs_cache.c
@@ -5337,12 +5337,14 @@ cache_fplookup_symlink(struct cache_fpl *fpl)
        struct nameidata *ndp;
        struct componentname *cnp;
        struct vnode *dvp, *tvp;
+       struct pwd *pwd;
        int error;
 
        ndp = fpl->ndp;
        cnp = fpl->cnp;
        dvp = fpl->dvp;
        tvp = fpl->tvp;
+       pwd = *(fpl->pwd);
 
        if (cache_fpl_islastcn(ndp)) {
                if ((cnp->cn_flags & FOLLOW) == 0) {
@@ -5398,6 +5400,9 @@ cache_fplookup_symlink(struct cache_fpl *fpl)
                        cache_fpl_checkpoint(fpl);
                        return (cache_fpl_partial(fpl));
                }
+               if (__predict_false(pwd->pwd_adir != pwd->pwd_rdir)) {
+                       return (cache_fpl_aborted(fpl));
+               }
        }
        return (0);
 }