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BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; MIME_TRACE(0.00)[0:+]; RCPT_COUNT_SEVEN(0.00)[9]; RCVD_TLS_ALL(0.00)[]; TO_DN_SOME(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.cz:mid,suse.cz:dkim,suse.cz:email]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; DKIM_TRACE(0.00)[suse.cz:+] X-Spam-Flag: NO X-Spam-Level: X-Rspamd-Queue-Id: 20C1576481 X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: no action X-Spam-Score: -4.51 We will want to do the validation earlier in some callers or remove it completely, so extract it from check_slab() first. No functional change. Signed-off-by: Vlastimil Babka Reviewed-by: Harry Yoo --- mm/slub.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 5bbfe4ee8d9846ec9a34584c10750388849da3b9..94a089205a86f0667444484e158= d307e72cd96e1 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1458,15 +1458,15 @@ static int check_object(struct kmem_cache *s, struc= t slab *slab, return ret; } =20 +/* + * Checks if the slab state looks sane. Assumes the struct slab pointer + * was either obtained in a way that ensures it's valid, or validated + * by validate_slab_ptr() + */ static int check_slab(struct kmem_cache *s, struct slab *slab) { int maxobj; =20 - if (!validate_slab_ptr(slab)) { - slab_err(s, slab, "Not a valid slab page"); - return 0; - } - maxobj =3D order_objects(slab_order(slab), s->size); if (slab->objects > maxobj) { slab_err(s, slab, "objects %u > max %u", @@ -1633,6 +1633,11 @@ void setup_slab_debug(struct kmem_cache *s, struct s= lab *slab, void *addr) static inline int alloc_consistency_checks(struct kmem_cache *s, struct slab *slab, void *object) { + if (!validate_slab_ptr(slab)) { + slab_err(s, slab, "Not a valid slab page"); + return 0; + } + if (!check_slab(s, slab)) return 0; =20 @@ -3485,6 +3490,11 @@ static inline bool free_debug_processing(struct kmem= _cache *s, int cnt =3D 0; =20 if (s->flags & SLAB_CONSISTENCY_CHECKS) { + if (!validate_slab_ptr(slab)) { + slab_err(s, slab, "Not a valid slab page"); + goto out; + } + if (!check_slab(s, slab)) goto out; } @@ -6519,6 +6529,11 @@ static void validate_slab(struct kmem_cache *s, stru= ct slab *slab, void *p; void *addr =3D slab_address(slab); =20 + if (!validate_slab_ptr(slab)) { + slab_err(s, slab, "Not a valid slab page"); + return; + } + if (!check_slab(s, slab) || !on_freelist(s, slab, NULL)) return; =20 --=20 2.51.0